How to Breathe Correctly for Optimal Health, Mood, Learning & Performance

00:00:00.000 | - Welcome to the Huberman Lab Podcast,

00:00:02.260 | where we discuss science and science-based tools

00:00:04.900 | for everyday life.

00:00:05.900 | I'm Andrew Huberman,

00:00:10.080 | and I'm a professor of neurobiology and ophthalmology

00:00:12.940 | at Stanford School of Medicine.

00:00:14.820 | Today, we are discussing breathing.

00:00:16.980 | Now, breathing is something that we are all familiar with

00:00:19.060 | because frankly, we are all doing it right now,

00:00:21.860 | and we do it during our waking states

00:00:24.220 | and while we are asleep.

00:00:26.140 | And most of us have probably heard

00:00:27.460 | that breathing is essential to life.

00:00:29.700 | We hear that we can survive without food

00:00:31.420 | for some period of time, maybe even up to a month or more.

00:00:34.460 | That we can't survive that long without water,

00:00:36.340 | but we could survive a few days without water,

00:00:38.000 | depending on how well hydrated we are

00:00:39.500 | when we go into that water deprivation

00:00:41.580 | and the heat of the environment we happen to be in.

00:00:44.580 | But that we cannot survive without breathing

00:00:47.200 | for more than a few minutes.

00:00:48.620 | That if we cease to breathe,

00:00:50.460 | that our brain and our bodily tissues will die.

00:00:53.140 | And in fact, that is true.

00:00:54.480 | However, despite everybody's knowledge

00:00:57.280 | that breathing is essential to life,

00:00:59.420 | I don't think that most people realize

00:01:00.760 | just how important how we breathe is

00:01:03.420 | to our quality of life.

00:01:04.820 | And that includes our mental health,

00:01:06.860 | our physical health, and what we call performance.

00:01:09.060 | That is our ability to tap into skills,

00:01:11.220 | either physical or cognitive,

00:01:13.140 | in ways that we would not be able to otherwise

00:01:15.900 | if we are not breathing correctly.

00:01:17.540 | So today we are going to talk about

00:01:18.900 | what it is to breathe correctly,

00:01:21.020 | both at rest, during sleep,

00:01:24.060 | in order to reduce our levels of stress,

00:01:26.900 | in order to wake up or to become more alert deliberately,

00:01:31.140 | and many, many other things,

00:01:32.380 | including how to stop hiccupping.

00:01:33.780 | This is one of the most searched for topics on the internet.

00:01:36.500 | Today, I will teach you the one method

00:01:38.180 | that is actually linked to science.

00:01:40.660 | No, it does not involve drinking a glass of water backwards

00:01:43.700 | from the opposite side of the cup

00:01:45.300 | or holding your breath in any kind of esoteric way.

00:01:48.860 | It actually relates to the neural mechanisms,

00:01:51.460 | that is the brain to body connections that cause the hiccup.

00:01:54.820 | Hiccup is a spasm of that neural circuit,

00:01:57.380 | and I'll teach you how to turn off

00:01:58.660 | that neural circuit in one try.

00:02:01.300 | And that's not a technique I developed.

00:02:03.180 | It's a technique that's actually been known about

00:02:05.420 | for several centuries,

00:02:07.300 | and we now know the underlying mechanism.

00:02:09.580 | So today's discussion will give to you many tools

00:02:12.860 | that you can apply.

00:02:14.540 | All of these tools are, of course, behavioral tools.

00:02:17.460 | They're completely zero cost.

00:02:18.780 | And in telling you how those tools work,

00:02:21.460 | you'll learn a lot about how the breathing,

00:02:23.820 | AKA the respiratory system works,

00:02:25.600 | and how it interfaces with the other organs and tissues

00:02:28.260 | of the body, in particular, the brain.

00:02:30.700 | In fact, one of the most important things to understand

00:02:32.580 | about breathing right here at the outset

00:02:34.940 | is that breathing is unique among brain and bodily functions

00:02:38.600 | in that it lies at the interface

00:02:40.460 | between our conscious and our subconscious behavior,

00:02:43.740 | and it represents a bridge, literally, in the brain

00:02:46.660 | between the conscious and the subconscious.

00:02:49.380 | What do I mean by that?

00:02:50.940 | Well, breathing does not require that we pay attention

00:02:53.800 | to our breathing or that we are even aware

00:02:55.440 | that we are breathing.

00:02:56.280 | It will just carry on in the background,

00:02:58.300 | either normally or abnormally,

00:02:59.860 | and I'll teach you what normal and abnormal breathing is

00:03:02.100 | in a little bit.

00:03:03.420 | However, breathing is unique among brain

00:03:05.600 | and bodily functions in that at any moment,

00:03:08.620 | we can consciously take control of how we breathe.

00:03:11.860 | This is an absolutely spectacular

00:03:13.780 | and highly unusual feature of brain function.

00:03:16.420 | For instance, your digestion is carrying on

00:03:18.900 | in the background right now,

00:03:19.920 | whether or not you've had food recently or not,

00:03:22.660 | but you can't simply control your digestion

00:03:24.940 | by thinking about it in a particular way.

00:03:26.520 | In fact, most people can't even control their thinking

00:03:29.580 | by trying to control their thinking.

00:03:30.780 | That actually takes some practice.

00:03:31.960 | It can be done, a topic for a future episode.

00:03:34.420 | However, breathing is unique.

00:03:36.420 | Breathing will carry on involuntarily, subconsciously

00:03:40.360 | in the background, as I said before,

00:03:42.040 | but if at any moment you want to hold your breath

00:03:44.400 | or inhale more deeply or vigorously

00:03:46.940 | or exhale longer than you inhale, you can do that.

00:03:49.760 | Very few, if any other neural circuits in your brain

00:03:53.620 | and body allow that level of control.

00:03:56.100 | And it turns out that level of control is not an accident.

00:03:59.740 | It has been hypothesized that by controlling breathing,

00:04:03.940 | the brain is actually attempting

00:04:05.860 | to control its own state of mind.

00:04:09.180 | Now, the way this was originally stated

00:04:11.620 | in a scientific research paper

00:04:13.780 | was a little bit different.

00:04:14.620 | It was a little bit more physiological.

00:04:16.000 | The statement was the brain by regulating breathing

00:04:19.180 | controls its own excitability.

00:04:21.400 | Excitability in the context of neurobiology

00:04:23.900 | is how able the brain is to take in new information or not,

00:04:28.720 | how able the brain is or not to turn itself off

00:04:32.420 | to go to sleep and to regulate its own levels

00:04:35.920 | of anxiety, focus, et cetera.

00:04:38.620 | If that seems a little bit abstract,

00:04:40.800 | I'll make it simple for you.

00:04:42.120 | By changing your pattern of breathing,

00:04:44.500 | you can very quickly change

00:04:47.160 | what your brain is capable of doing.

00:04:48.680 | In fact, a little bit later,

00:04:49.860 | I'll tell you that while you inhale,

00:04:52.320 | you are far better at learning and remembering information

00:04:55.560 | than during an exhale.

00:04:56.580 | And it is a very significant difference.

00:04:59.060 | Does that mean you should only inhale and not exhale?

00:05:00.920 | No, of course not.

00:05:02.100 | I'll teach you how to breathe

00:05:03.280 | for the sake of learning and memory,

00:05:05.140 | as well as for physical performance

00:05:07.360 | and a number of other things.

00:05:08.720 | So hopefully I've been able to highlight for you

00:05:10.480 | the importance of breathing, not just for life,

00:05:13.060 | because yes, breathing is essential for life,

00:05:15.780 | but that the subtleties of how we breathe,

00:05:18.360 | the duration and intensity of our inhales and our exhales,

00:05:22.900 | how long we hold our breath between inhales and exhales,

00:05:26.560 | very critically defines our state of mind

00:05:30.320 | and our state of body,

00:05:31.480 | what we are able to do and what we are not able to do.

00:05:33.960 | And the great news is we can control our breathing

00:05:36.800 | and in doing so control our mental health,

00:05:39.360 | physical health and performance.

00:05:41.200 | Before we begin, I'd like to emphasize that this podcast

00:05:43.720 | is separate from my teaching and research roles at Stanford.

00:05:46.420 | It is, however, part of my desire and effort

00:05:48.600 | to bring zero cost to consumer information about science

00:05:51.140 | and science-related tools to the general public.

00:05:53.660 | In keeping with that theme,

00:05:54.780 | I'd like to thank the sponsors of today's podcast.

00:05:57.660 | Our first sponsor is HVMN.

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00:09:23.820 | Let's talk about breathing.

00:09:25.500 | And of course we breathe

00:09:26.740 | in order to bring oxygen into the body,

00:09:29.420 | but we also breathe to remove certain things from our body,

00:09:32.220 | in particular carbon dioxide.

00:09:34.020 | So the main players in today's discussion

00:09:36.060 | are going to be oxygen and carbon dioxide.

00:09:38.740 | Now a common misconception is that oxygen is good

00:09:41.880 | and carbon dioxide is bad.

00:09:43.780 | That's simply not the case.

00:09:45.620 | Let's just take a step back from that statement

00:09:48.100 | and let's think about this.

00:09:49.560 | When we breathe in, we are largely breathing in air

00:09:53.080 | in order to bring oxygen into our body.

00:09:55.820 | And we can just stop right there and say,

00:09:57.320 | why do we breathe at all?

00:09:58.780 | Why can't we just get oxygen from the world around us?

00:10:01.160 | Well, it's because oxygen can't diffuse through our skin

00:10:05.020 | into the deeper cells of our body.

00:10:06.840 | Other single cell and very simple organisms

00:10:10.460 | can actually bring oxygen into their system

00:10:12.360 | without the need to breathe.

00:10:14.000 | But we have to breathe in order to bring oxygen

00:10:16.800 | to the cells that reside deep in our body.

00:10:18.680 | In particular, our brain cells,

00:10:20.320 | which are the most metabolically active cells in our body

00:10:22.400 | require a lot of oxygen.

00:10:24.400 | And those brain cells are sitting of course in the brain,

00:10:27.600 | which is encased in the cranial vault, the skull.

00:10:30.600 | And so oxygen can't simply pass to those cells.

00:10:32.960 | So we need to have a system

00:10:34.880 | that will deliver oxygen to those cells.

00:10:37.320 | We also need a system,

00:10:39.000 | which turns out to be the breathing or respiratory system

00:10:41.640 | that can offload or remove the gas

00:10:44.980 | that we call carbon dioxide.

00:10:46.260 | Not because carbon dioxide is bad,

00:10:48.360 | but because too much of it in our system is not good.

00:10:50.740 | In fact, much of today's discussion

00:10:52.220 | will also center around the common misconception

00:10:55.680 | that carbon dioxide is something that we want to get rid of.

00:10:58.600 | You don't want to get rid of too much carbon dioxide

00:11:01.600 | or else you can't actually get oxygen

00:11:04.240 | to the cells and tissues of your body in an efficient way.

00:11:07.240 | So you need oxygen and you need carbon dioxide in your body.

00:11:11.220 | You also need to be able to offload or remove carbon dioxide

00:11:15.480 | and bring in oxygen in the correct ratios

00:11:18.360 | so that you can perform the kind of mental functions

00:11:20.660 | and physical functions that you want to.

00:11:23.080 | So if we just dial out even further,

00:11:25.800 | we say, what are the key components of breathing?

00:11:29.360 | What are the elements within the body

00:11:32.300 | that allow us to bring oxygen to the tissues and cells

00:11:35.920 | as is required and remove carbon dioxide from the body

00:11:39.120 | as is required and yet keep enough carbon dioxide around

00:11:42.040 | in order to allow oxygen to do its thing?

00:11:44.840 | Well, that breathing or respiratory apparatus

00:11:48.880 | has two major components

00:11:50.300 | and I'm going to just briefly describe those.

00:11:52.120 | And as I do this, I really want to highlight the fact

00:11:54.800 | that anytime you're thinking about biology

00:11:57.320 | and physiology in particular,

00:11:58.800 | whether or not it's about the brain or the liver

00:12:00.600 | or the gut microbiome, it's useful to categorize things

00:12:04.640 | either as mechanical mechanisms or chemical mechanisms.

00:12:09.640 | What do I mean by that?

00:12:11.100 | Well, let's just take the analogy of hunger.

00:12:13.480 | There are mechanical mechanisms

00:12:15.660 | that tell us when we should eat.

00:12:17.560 | For instance, you have neurons, nerve cells in your gut

00:12:20.100 | that signal how stretched or non-stretched

00:12:24.600 | the walls of your stomach are, right?

00:12:27.040 | How full or how empty your gut is

00:12:28.820 | and send that information to the brain

00:12:31.440 | to make you feel to some extent hungry or not hungry.

00:12:35.220 | In general, when our stomach is very full,

00:12:37.780 | especially if it's very distended, even with liquid,

00:12:40.960 | it suppresses our hunger.

00:12:42.120 | Whereas when our stomach is devoid

00:12:44.640 | of that mechanical pressure,

00:12:46.200 | especially for a number of hours,

00:12:47.780 | it tends to trigger hunger

00:12:49.000 | by signaling via neurons to the brain.

00:12:52.120 | In addition, there are chemical signals

00:12:54.440 | that go from the gut to the brain.

00:12:56.080 | For instance, we have neurons in our gut

00:12:58.120 | that can detect the presence of amino acids from proteins

00:13:01.660 | that we eat, fatty acids from the foods that we eat,

00:13:04.740 | the lipids, and sugars, different forms of carbohydrate.

00:13:09.400 | The neurons in our gut are paying attention to

00:13:12.060 | or respond to how much amino acid, fatty acid,

00:13:16.500 | and carbohydrate is in our gut

00:13:17.980 | and send signals to the brain

00:13:19.540 | to either stimulate or suppress hunger.

00:13:21.800 | So those are chemical signals

00:13:23.680 | that are being passed from gut to brain

00:13:25.140 | and they work in parallel with the mechanical signals.

00:13:28.640 | And this idea of in parallel with,

00:13:30.360 | again, is a very common theme in biology,

00:13:32.280 | especially neuroscience.

00:13:33.660 | The term parallel pathways refers to the fact

00:13:35.760 | that anytime there's a critical bodily function,

00:13:38.980 | it's very unlikely that just one type of information,

00:13:41.800 | like just mechanical information is going to be used.

00:13:44.900 | Almost always, it's going to be mechanical

00:13:47.280 | and chemical information.

00:13:49.160 | I could pick a number of other examples.

00:13:51.180 | For instance, if you want to avoid damaging your skin

00:13:55.180 | or other tissues of your body, which is essential to life,

00:13:58.000 | well then you have mechanical information about,

00:14:01.240 | for instance, whether or not something is pinching

00:14:03.540 | or ready to pierce your skin, that's mechanical information.

00:14:06.800 | It's sent via specific neurons up to the brain

00:14:10.020 | to signal a retraction reflex.

00:14:12.020 | If you move your limb away

00:14:13.260 | from wherever that intense pressure is coming.

00:14:15.420 | You also have chemical sensing in your skin,

00:14:17.620 | the presence of things that elicit a burn

00:14:21.500 | or that elicit itch or that elicit extreme cold.

00:14:25.220 | All of that chemical information is being signaled

00:14:27.860 | up to the brain as well in parallel.

00:14:29.340 | So parallel pathways is a common theme.

00:14:31.240 | So when we're thinking about the respiration,

00:14:32.980 | AKA the breathing system,

00:14:35.320 | we also need to look at the mechanical system.

00:14:37.160 | What are the different components of the nose, the mouth,

00:14:39.460 | the lungs, et cetera, that allow oxygen to be brought in

00:14:42.620 | and carbon dioxide to be removed from the body,

00:14:45.080 | but not too much carbon dioxide removed

00:14:47.380 | to allow breathing to work as efficiently

00:14:50.060 | and as optimally as possible.

00:14:52.460 | And then we also need to look at the chemical systems

00:14:54.880 | of the lungs, the bloodstream,

00:14:57.940 | and how different cells use oxygen and carbon dioxide

00:15:01.100 | in order to understand that as well.

00:15:03.660 | If you can understand the mechanical

00:15:05.460 | and chemical aspects of breathing,

00:15:07.620 | even just at a top contour,

00:15:09.800 | well then the various tools that I discussed

00:15:11.840 | during today's episode,

00:15:13.300 | such as the ability to calm yourself down most quickly

00:15:17.220 | by doing what's called a physiological sigh.

00:15:19.560 | I'll go into this in more detail in a little bit,

00:15:21.180 | but this is two very deep inhales through the nose.

00:15:24.660 | So the first one is a long inhale.

00:15:26.620 | And then the second one after that is a quick,

00:15:30.500 | sharp inhale to maximally inflate your lungs,

00:15:33.100 | followed by a full exhale through the mouth

00:15:36.220 | to lungs completely empty.

00:15:38.180 | So it's big inhale through the nose,

00:15:40.440 | then short inhale through the nose immediately after that

00:15:43.980 | in order to maximally inflate the lungs.

00:15:46.140 | And then a long exhale through the mouth

00:15:48.940 | until your lungs are empty.

00:15:51.100 | You will understand why that particular pattern

00:15:53.600 | of breathing and not simply one inhale,

00:15:56.420 | or not simply an inhale through the nose

00:15:58.260 | and an exhale through the nose as well,

00:16:00.880 | is optimal for reducing your stress quickly.

00:16:04.220 | That double inhale through the nose

00:16:05.740 | followed by a long exhale through the mouth

00:16:08.260 | works to reduce your levels of stress

00:16:11.740 | and lower your levels of so-called autonomic arousal

00:16:14.700 | very fast in real time.

00:16:16.340 | And it works better than any other known approach.

00:16:19.580 | It's not a hack.

00:16:20.620 | This is actually something that your body

00:16:22.080 | has specific neural circuits to do.

00:16:24.100 | And it actually performs during sleep on a regular basis

00:16:27.020 | and even throughout the day.

00:16:28.220 | And that you can perform voluntarily.

00:16:30.500 | And it works so well to reduce stress very quickly,

00:16:33.460 | not because it brings in the maximum amount of oxygen

00:16:36.740 | and removes the maximum amount of carbon dioxide,

00:16:38.740 | but rather because it optimally balances

00:16:41.580 | oxygen and carbon dioxide.

00:16:43.340 | If you understand the mechanical

00:16:44.720 | and chemical aspects of breathing,

00:16:46.700 | then you will understand exactly why

00:16:48.300 | that particular pattern of breathing,

00:16:49.920 | the so-called physiological psi,

00:16:51.880 | is the most efficient way to rapidly reduce stress

00:16:54.940 | in real time.

00:16:55.980 | If you can understand the mechanical

00:16:57.300 | and chemical aspects of breathing,

00:16:59.000 | you will also understand why most people are over-breathing,

00:17:04.000 | that is they're breathing too often,

00:17:05.900 | even if they're breathing in a shallow manner,

00:17:08.380 | they're breathing too often,

00:17:10.460 | and they are blowing off or removing too much carbon dioxide.

00:17:14.340 | And if you understand that carbon dioxide is critical

00:17:16.780 | for the way that oxygen is delivered from the bloodstream

00:17:19.420 | to the tissues of the body, including the brain,

00:17:22.280 | well, then it will make very good sense

00:17:24.140 | as to why people who are breathing too much

00:17:27.000 | don't actually experience all the effects of elevated oxygen

00:17:30.820 | but rather they're putting their body

00:17:32.780 | into what's called a hypoxic state.

00:17:34.480 | They're not getting enough oxygen

00:17:36.420 | to the tissues of their body, in particular, their brain.

00:17:38.860 | And this is true not just for people

00:17:40.140 | who are obese or who suffer from sleep apnea,

00:17:42.780 | or although that's certainly the case,

00:17:44.880 | but for people that have, believe it or not,

00:17:47.120 | certain personality types.

00:17:48.720 | We'll talk about breathing and personality type

00:17:50.540 | and actually how breathing has been shown

00:17:52.340 | to alter personality, that's right.

00:17:54.500 | Breathing can alter personality in positive ways

00:17:57.380 | that allow anyone to show up to the various social

00:18:01.020 | and non-social endeavors of their life with more calm,

00:18:03.540 | more focus, alertness, and improve their overall health.

00:18:06.700 | Okay, so let's talk about the mechanical components

00:18:08.920 | of breathing.

00:18:09.760 | It's really quite simple.

00:18:11.380 | You've got your nose, obviously, and you've got your mouth.

00:18:14.920 | And a little bit later, we'll talk about

00:18:16.280 | the incredible advantages of being a nasal breather

00:18:19.980 | most of the time, but also the incredible advantages

00:18:23.780 | of using your mouth to breathe both for inhales and exhales

00:18:27.380 | during particular types of endeavors.

00:18:30.400 | And we'll get back to that a little later.

00:18:32.620 | But for the meantime, the only two ways to bring air

00:18:36.080 | into your system are through your nose

00:18:38.700 | and through your mouth.

00:18:40.740 | We also have the larynx, which is a rigid tissue or pipe

00:18:45.000 | that brings the air from the nose and mouth

00:18:47.360 | down to the lungs.

00:18:49.240 | Now, that word rigid is really important here

00:18:52.060 | because what we will soon learn is that your lungs

00:18:55.340 | basically act like a pump.

00:18:57.620 | You sort of know this already,

00:18:58.700 | but these are two big bags basically that can fill with air

00:19:02.860 | or that can squeeze air out.

00:19:05.660 | Now, what most people don't realize is that the lungs

00:19:08.060 | are not just two big bags of air.

00:19:10.300 | Your lungs are actually two big bags of air

00:19:12.660 | that inside of them have hundreds of millions

00:19:14.740 | of little sacs that are called the avioli of the lungs.

00:19:16.960 | And by having those hundreds of millions of little sacs,

00:19:19.560 | you increase the surface area of the lungs.

00:19:22.820 | And by increasing the surface area,

00:19:24.660 | you allow more oxygen to pass from the air in your lungs

00:19:28.620 | into the bloodstream than if you didn't have those sacs.

00:19:32.820 | And you allow more carbon dioxide to move

00:19:35.740 | from the bloodstream into those sacs of the lungs.

00:19:38.380 | And then when you exhale,

00:19:39.300 | the carbon dioxide can be removed, okay?

00:19:41.160 | So those little sacs we call avioli of the lungs

00:19:43.580 | are an important part of the mechanical aspect of breathing.

00:19:46.860 | We'll get to a little bit later.

00:19:48.740 | Okay, so at a first pass,

00:19:51.020 | the mechanical aspects of breathing

00:19:52.440 | are really straightforward, right?

00:19:53.580 | You can breathe through your nose.

00:19:54.500 | You can breathe through your mouth.

00:19:55.500 | It goes down through the larynx.

00:19:56.600 | I told you the larynx is a rigid pipe.

00:19:58.800 | The lungs are not rigid.

00:19:59.960 | They can expand and they can contract like a pump

00:20:02.400 | to bring in air or to expel air.

00:20:06.060 | Now, keep in mind that the lungs

00:20:08.220 | do not have any muscles themselves.

00:20:10.460 | So we need muscles that can either squeeze the lungs

00:20:14.880 | or that will allow the lungs to expand.

00:20:17.380 | And there are two general groups of muscles that do that.

00:20:19.940 | And they are the diaphragm

00:20:21.620 | and the so-called intercostal muscles.

00:20:24.020 | The diaphragm is a thin muscle that sits below the lungs

00:20:26.980 | and above the liver.

00:20:28.660 | And when we inhale,

00:20:30.900 | provided that we are using

00:20:32.180 | what's called diaphragmatic breathing,

00:20:34.540 | that diaphragm contracts.

00:20:37.020 | And when it contracts, it moves down,

00:20:39.020 | which allows more space for the lungs to inflate with air.

00:20:42.760 | Now, the intercostal muscles

00:20:45.460 | are the muscles between our ribs.

00:20:47.460 | A number of people probably don't realize this,

00:20:49.120 | but your ribs, of course, are bone,

00:20:50.900 | but in between those bones, you have muscles.

00:20:52.780 | And the intercostal muscles, when you inhale, contract,

00:20:56.660 | and that allows your rib cage to move up

00:20:59.160 | and to expand a bit.

00:21:00.820 | And I think, again,

00:21:01.700 | people probably don't realize

00:21:02.620 | that your ribs are not fixed in place.

00:21:04.220 | They can actually get further

00:21:06.100 | and closer apart from one another.

00:21:08.060 | So when you inhale, your rib cage actually moves up.

00:21:11.140 | Sometimes the shoulders will move up as well.

00:21:13.620 | And that's because those intercostal muscles

00:21:15.740 | are contracting.

00:21:17.020 | Now, muscles can't move on their own.

00:21:20.940 | They are controlled by nerves.

00:21:22.660 | So we've got the nose, the mouth, the larynx, and the lungs.

00:21:26.300 | The lungs have all those little avioli in them.

00:21:27.980 | And as I told you,

00:21:28.820 | we've got the diaphragm as a muscle to move the lungs,

00:21:32.820 | and we have the intercostal muscles to move the ribs,

00:21:35.860 | which can allow the lungs to expand.

00:21:37.740 | Again, we're just on the mechanical components of breathing,

00:21:40.020 | but because muscles can't move themselves,

00:21:42.120 | you should be asking what moves the muscles.

00:21:44.220 | And it's really nerves that control muscles.

00:21:48.460 | So whether or not you're contracting your biceps

00:21:51.020 | or you're walking and you're contracting your quadriceps

00:21:53.580 | and your hamstrings and your calf muscles,

00:21:55.720 | it's neurons, nerve cells that control that.

00:21:58.500 | There's a specialized nerve called the phrenic nerve,

00:22:02.180 | P-H-R-E-N-I-C, phrenic nerve,

00:22:06.160 | that comes out of the neck.

00:22:08.700 | And when I say it comes out of the neck,

00:22:10.220 | what I mean is that they're little neurons

00:22:11.780 | that reside in the brainstem, in the back of your brain,

00:22:15.260 | and they send little wires that we call axons

00:22:18.060 | down and out of the neck.

00:22:20.860 | They go through close to the heart

00:22:23.220 | and a little bit behind it,

00:22:24.460 | and they go down and they form synapses.

00:22:26.960 | That is, they form connections with the diaphragm.

00:22:30.180 | And when those neurons release neurotransmitter,

00:22:32.980 | which are little chemicals,

00:22:33.820 | the diaphragm contracts and it moves down.

00:22:36.340 | So we say that the phrenic nerve is a motor nerve.

00:22:38.820 | It's designed to move muscle.

00:22:40.960 | However, the phrenic nerve,

00:22:42.780 | like a few other nerves in the body,

00:22:44.640 | is interesting in that it has not just motor nerves

00:22:48.180 | in there, neurons that control the contraction of muscles,

00:22:51.260 | it also can sense things.

00:22:53.900 | There has sensory neurons.

00:22:56.180 | So it also sends connections down to the diaphragm

00:22:59.340 | and actually down deep into the diaphragm

00:23:01.620 | and close to the liver.

00:23:03.160 | And note that I said liver twice now already,

00:23:05.700 | and we're going to get back to this later

00:23:06.760 | when we talk about physical movement and cramps of the body.

00:23:10.180 | Those sensory neurons dive deep into the diaphragm,

00:23:14.260 | and then they go back up to the brain

00:23:16.220 | and they allow you to sense where the diaphragm is.

00:23:19.340 | So they're giving information

00:23:20.740 | about where the diaphragm is in your body.

00:23:22.740 | Now, most of the time, you're not paying attention to this,

00:23:24.760 | but right now you can actually try this,

00:23:26.220 | and I would encourage you to do this.

00:23:27.820 | Diaphragmatic breathing is in many ways

00:23:30.860 | the ideal way to breathe

00:23:32.380 | and that it's the most efficient way to breathe.

00:23:34.380 | We'll talk about what we mean exactly

00:23:36.100 | when we say breathing efficiency later,

00:23:38.720 | but the diaphragm is designed to allow the lungs to expand

00:23:43.460 | or to contract the lungs to bring air into the body

00:23:46.260 | or to remove carbon dioxide from the body.

00:23:49.000 | And if you want to know whether or not

00:23:51.200 | you're using diaphragmatic breathing, it's very simple.

00:23:54.100 | If you inhale, probably best to do this through the nose,

00:23:56.900 | but you could do it through the mouth.

00:23:58.300 | If you inhale and your belly moves outward on the inhale,

00:24:02.340 | well, then that phrenic nerve

00:24:03.580 | is controlling your diaphragm properly.

00:24:05.900 | And then when you exhale,

00:24:07.260 | your belly should go in just a little bit.

00:24:09.300 | That's diaphragmatic breathing.

00:24:11.740 | Now, diaphragmatic breathing is talked about

00:24:14.380 | in the context of yoga.

00:24:15.740 | It's often talked about as a way to calm down and so on.

00:24:18.940 | But diaphragmatic breathing is just one mode

00:24:20.720 | by which your brain and the phrenic nerve

00:24:22.980 | can control muscle, the diaphragm,

00:24:24.620 | to control the mechanical aspects of the lungs

00:24:27.660 | to bring in air and expel air.

00:24:30.160 | As I mentioned before,

00:24:31.000 | you also have these muscles between your ribs

00:24:32.880 | or the intercostal muscles.

00:24:34.540 | And there's a separate set of nerves

00:24:36.820 | that allow those muscles to contract

00:24:38.460 | and for your rib cage to expand

00:24:40.300 | in order to create more room for your lungs

00:24:42.760 | to get larger and fill with air

00:24:44.660 | or for your rib cage to contract a bit

00:24:47.380 | when those muscles relax in order to expel air.

00:24:51.040 | I'd like to go on record by saying

00:24:53.480 | that there is no rule that diaphragmatic breathing

00:24:57.120 | is better than breathing where your rib cage moves.

00:25:00.420 | This is a common misconception.

00:25:01.740 | People say, "Oh, if your shoulders are going up and down

00:25:03.900 | and your rib cage is moving while you're breathing,

00:25:06.900 | well, then you're not breathing right.

00:25:08.140 | And if your belly goes out

00:25:09.740 | and the rest of your body is still while you breathe,

00:25:12.360 | well, then you're breathing correctly."

00:25:13.820 | I know of zero, in fact, zero minus one data

00:25:18.220 | to support that statement.

00:25:19.300 | You have multiple parallel mechanisms

00:25:21.800 | to control the mechanics of your lungs and for breathing.

00:25:24.860 | And when you're exerting yourself very hard,

00:25:26.500 | you tend to use both the intercostal muscles

00:25:28.740 | and your rib cage moving as well as your diaphragm

00:25:31.500 | in order to bring in a lot of oxygen

00:25:33.540 | and to offload a lot of carbon dioxide.

00:25:35.980 | And when you're calmer,

00:25:37.220 | frankly, you could use diaphragmatic breathing

00:25:39.200 | or you could use rib cage type breathing

00:25:42.120 | in order to bring enough oxygen into your system.

00:25:44.660 | There's no real data showing that diaphragmatic breathing

00:25:48.780 | is somehow better or worse.

00:25:50.460 | However, being able to mechanically control

00:25:53.480 | those independently or to combine them

00:25:55.280 | and use them together is of tremendous power

00:25:57.760 | toward regulating your mental and physical states.

00:26:00.160 | And we'll talk about how to do that a little bit later.

00:26:01.760 | For right now, please understand

00:26:03.680 | that you have these different mechanical components

00:26:06.500 | that allow you to bring oxygen into your system

00:26:08.780 | and to expel air

00:26:12.020 | and to thereby offload carbon dioxide from your system.

00:26:15.360 | Again, we haven't talked about the gas exchange

00:26:18.380 | of carbon dioxide and oxygen

00:26:19.860 | and how that's happening in the bloodstream.

00:26:21.020 | We'll talk about that next.

00:26:22.140 | But the basic mechanical components are pretty simple.

00:26:24.740 | Once again, just to review,

00:26:25.700 | it's nose, mouth, larynx, lungs,

00:26:29.100 | avioli within the lungs, and then those two muscles,

00:26:31.540 | the diaphragm and the intercostal muscles of the ribs.

00:26:34.220 | And one thing I failed to mention

00:26:36.320 | is why it's so important that that larynx be rigid,

00:26:40.100 | that it's a tube that is very rigid.

00:26:42.740 | And the reason for that is that unlike the lungs,

00:26:45.380 | which you want to act as sort of a bellow pump

00:26:48.300 | where you can deflate it and inflate it

00:26:51.180 | in order to move air in and out,

00:26:53.760 | the larynx needs to be rigid so that it doesn't collapse

00:26:57.340 | while you're bringing air in and out.

00:26:58.860 | You can imagine that if it was a very flimsy tube

00:27:01.380 | or the walls of the larynx were very flimsy and thin,

00:27:04.400 | well, then you can imagine breathing in very vigorously

00:27:07.060 | and it would shut like a tube

00:27:09.580 | that suddenly flattens on itself, which would not be good.

00:27:12.580 | So the fact that the larynx is rigid

00:27:14.660 | is actually a very crucial part of this whole system.

00:27:17.540 | The other important aspect of this system

00:27:20.020 | as it relates to the mechanics of breathing

00:27:22.300 | is the fact that your nose and your mouth

00:27:24.740 | have different resistances to air.

00:27:27.020 | You can probably notice this right now

00:27:29.260 | if you were to, for instance,

00:27:30.260 | breathe in through your mouth and only through your mouth

00:27:32.940 | versus breathe in through your nose.

00:27:34.700 | Some of you perhaps have a harder time

00:27:36.540 | breathing in through your nose.

00:27:37.540 | By the way, it's perfectly normal

00:27:38.920 | that one or the other nostril

00:27:41.000 | would be harder to breathe through

00:27:42.820 | or easier to breathe through

00:27:43.660 | and that that switches across the day.

00:27:45.160 | It has to do with the flow of mucus and cerebral spinal fluid

00:27:48.120 | and intracranial pressure, totally normal.

00:27:50.900 | Many people out there think they have a deviated septum

00:27:53.200 | who don't actually have a deviated septum.

00:27:55.000 | A little bit later, we'll talk about

00:27:55.960 | how to repair a deviated septum without surgery

00:27:58.480 | 'cause that actually is possible in many, not all cases

00:28:01.240 | and is immensely beneficial to do.

00:28:04.860 | But what we know is that breathing in through the nose

00:28:07.360 | is a little bit harder

00:28:08.600 | and it's supposed to be a little bit harder.

00:28:10.280 | However, because it's a little bit harder

00:28:13.200 | because there's more resistance as we say,

00:28:15.460 | you're actually able to draw more force

00:28:18.220 | into these mechanical aspects of the breathing apparatus

00:28:20.960 | and actually bring more air into your lungs.

00:28:24.600 | You can try this right now.

00:28:26.200 | Try breathing in through your mouth

00:28:27.680 | to maximally inflate your lungs

00:28:29.600 | and try and do it through mostly diaphragmatic breathing

00:28:32.840 | just for sake of example.

00:28:34.200 | In other words, try and breathe in through your mouth

00:28:36.200 | and as you do that, have your belly expand

00:28:38.040 | and maximally inflate your lungs.

00:28:39.440 | I'll do it right now with you

00:28:40.320 | so that we can do it together

00:28:42.160 | and I can prove to everyone

00:28:43.760 | that I'm just as deficient in this as you are.

00:28:46.680 | [gasps]

00:28:49.240 | Okay, so I can inflate my stomach doing that

00:28:51.760 | but now try doing it with your nose

00:28:53.640 | and please do exhale before you try doing it with your nose.

00:28:55.920 | With your nose, you're going to feel more resistance

00:28:57.680 | but you'll notice that you can inflate it

00:28:59.520 | quite a bit further.

00:29:00.540 | And you'll feel your entire cavity, your belly

00:29:05.600 | and maybe even in your lower back

00:29:07.160 | sort of fill with some pressure.

00:29:08.820 | So the increased resistance actually allows you

00:29:11.360 | to draw more air into the system.

00:29:14.180 | This turns out to be very important

00:29:15.680 | and it also wipes away a common misconception

00:29:17.920 | which is if you're somebody who has challenges

00:29:20.300 | breathing in through your nose

00:29:21.520 | that somehow you should avoid breathing in

00:29:23.460 | through your nose.

00:29:24.300 | Actually quite the opposite is true

00:29:25.420 | and we can go a step further and say

00:29:27.000 | that if you have challenges breathing in through your nose,

00:29:29.640 | chances are that's because the increased resistance

00:29:32.080 | of breathing in through your nose

00:29:33.260 | provided it's not completely occluded

00:29:36.000 | is going to allow you to bring more oxygen into your system.

00:29:39.360 | This will turn out to be useful later

00:29:41.060 | when we explore different techniques for instance

00:29:43.480 | not just to calm down quickly

00:29:44.800 | but to elevate your energy quickly,

00:29:47.140 | to remove a cramp during exercise

00:29:49.880 | and a number of other things that breathing can be used for

00:29:52.580 | that can be immensely useful

00:29:54.080 | for mental and physical challenges.

00:29:56.620 | I'd like to take a quick break

00:29:58.140 | and acknowledge one of our sponsors, Athletic Greens.

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00:30:13.680 | The reason I started taking Athletic Greens

00:30:15.280 | and the reason I still take Athletic Greens

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00:31:10.880 | So now let's talk about the chemical aspects of breathing.

00:31:13.300 | And the two major players in this discussion are oxygen,

00:31:16.020 | which all the cells and tissues of your body need

00:31:19.420 | and carbon dioxide,

00:31:21.240 | which all the cells and tissues of your body need.

00:31:24.020 | In fact, carbon dioxide plays critical roles

00:31:26.820 | in delivering oxygen to your cells.

00:31:28.660 | And without carbon dioxide,

00:31:30.180 | you're not going to get enough oxygen

00:31:31.780 | to the cells and tissues of your body.

00:31:34.880 | That said, if carbon dioxide levels are too high,

00:31:38.000 | that is very problematic.

00:31:39.140 | In fact, one of the ways

00:31:40.720 | that one can reliably induce panic in anybody

00:31:45.260 | is to have them breathe air

00:31:48.300 | that contains too much carbon dioxide.

00:31:50.760 | So much so that for people that lack a so-called amygdala,

00:31:55.000 | many of you have probably heard of the amygdala,

00:31:56.460 | this is a brain area that's associated with fear

00:31:58.920 | and threat detection,

00:32:00.000 | even in people who completely lack amygdalas

00:32:03.800 | on both sides of the brain,

00:32:05.060 | because they were removed,

00:32:06.060 | because they had epileptic seizures there.

00:32:08.040 | And therefore those people are completely unafraid

00:32:10.500 | of things that they ought to be afraid of,

00:32:12.080 | like heights, poisonous snakes,

00:32:14.560 | any number of different things, dangerous to humans.

00:32:18.020 | Well, if those people breathe

00:32:19.420 | an excess amount of carbon dioxide,

00:32:21.060 | they immediately have a panic attack.

00:32:23.180 | What that tells us is that,

00:32:24.700 | again, there are parallel mechanisms,

00:32:26.500 | there's redundancy in the system to protect ourselves

00:32:29.580 | from having too much carbon dioxide in our system.

00:32:32.340 | So we need enough carbon dioxide

00:32:34.240 | and enough oxygen in our system, but not too much.

00:32:37.160 | The way that's accomplished is that, of course,

00:32:41.260 | we breathe in air, our lungs inflate.

00:32:44.300 | And if you recall those little avioli of the lungs,

00:32:46.900 | those little sacs, oxygen can actually move from the air

00:32:51.040 | into those little sacs,

00:32:52.660 | and then from those little sacs into the vasculature.

00:32:55.840 | The vasculature are the capillaries,

00:32:58.020 | the veins and the arteries of the body,

00:33:00.140 | because the walls of those little avioli

00:33:02.580 | are exceedingly thin,

00:33:04.140 | and they have tons of little capillaries

00:33:06.500 | that go into them and are all around them.

00:33:09.820 | So this is amazing, right?

00:33:10.780 | There's oxygen literally passing

00:33:13.180 | from inside of these little sacs in our lungs,

00:33:16.740 | 'cause we inhaled the oxygen, from the air,

00:33:20.400 | into the bloodstream,

00:33:21.620 | and then that oxygen gets bound up by proteins in the blood,

00:33:26.540 | in particular hemoglobin,

00:33:28.140 | and hemoglobin then delivers oxygen

00:33:31.660 | to the very cells and tissues of the body.

00:33:34.300 | However, oxygen can't just hop on hemoglobin

00:33:38.420 | and cruise along with hemoglobin

00:33:40.240 | until it gets to, say, your brain, and then hop off.

00:33:42.840 | It doesn't work that way.

00:33:44.040 | You require carbon dioxide

00:33:47.100 | in order to liberate oxygen from hemoglobin.

00:33:49.800 | Carbon dioxide has this incredible property

00:33:53.380 | of actually being able to change the shape of hemoglobin.

00:33:56.300 | Hemoglobin is shaped as a sort of a cage

00:33:58.980 | around oxygen molecules,

00:34:00.900 | and when it's in that cage shape,

00:34:02.540 | the oxygen can't be liberated.

00:34:04.580 | So you've got oxygen and hemoglobin bound to one another

00:34:07.820 | moving through your bloodstream,

00:34:09.360 | but if a tissue needs oxygen,

00:34:12.780 | there needs to be carbon dioxide present

00:34:14.840 | to open up that cage,

00:34:17.380 | and that's what carbon dioxide does.

00:34:18.860 | It allows that cage to change shape,

00:34:21.360 | and then the oxygen can be liberated

00:34:23.520 | and then can be delivered to the tissues,

00:34:25.320 | whether or not that's brain tissue or muscle tissue,

00:34:27.760 | so on and so forth.

00:34:29.460 | And so those are the major chemical components of breathing.

00:34:32.380 | There are a few other aspects

00:34:34.280 | related to the chemical components of breathing,

00:34:35.920 | such as the fact that carbon dioxide

00:34:38.860 | is strongly related to how acidic

00:34:41.860 | or how basic your body is in general.

00:34:44.800 | So for instance, if carbon dioxide levels go way down,

00:34:48.400 | your blood pH goes way up.

00:34:51.300 | That is, you become more alkaline.

00:34:53.280 | Now, for many people, the word pH

00:34:54.980 | and the whole concept of pH

00:34:56.180 | immediately starts to evoke anxiety in and of itself.

00:34:59.440 | pH is actually very simple.

00:35:01.380 | You want the body basically to be at a pH of about 7.4.

00:35:05.900 | There are some regions of your body,

00:35:07.260 | in particular along the gut,

00:35:08.660 | for which that number is importantly different

00:35:11.100 | in order for digestion to work properly.

00:35:13.340 | You've all heard of the gut microbiome,

00:35:14.840 | the little microbes that provided you have enough of them

00:35:17.900 | and they're diverse enough allow your brain and body

00:35:21.020 | to function optimally at the level of immune system,

00:35:23.020 | hormone system, brain, et cetera.

00:35:25.400 | Well, in the gut,

00:35:26.960 | you want the pH sometimes to be slightly more acidic

00:35:30.640 | because when it's more acidic,

00:35:32.420 | the little microbiota flourish

00:35:35.180 | far more than if it were more basic,

00:35:37.260 | but basically you want the rest of the body

00:35:38.940 | to be at about pH 7.4.

00:35:41.460 | If carbon dioxide levels go too low,

00:35:44.080 | the pH increases in a way that you might say,

00:35:47.140 | oh, well, that's bad,

00:35:48.180 | but that actually allows more oxygen to be available

00:35:51.540 | to the tissues of your body at least temporarily.

00:35:53.380 | We'll talk about this a bit more later.

00:35:55.620 | If I'm losing any of you, just hang in there

00:35:57.260 | because we're almost done with this whole business

00:35:58.960 | of the mechanics and the chemistry of breathing

00:36:01.100 | and then we can get into the tools

00:36:02.500 | and revisit some of this later

00:36:04.040 | to clean up any misunderstandings that may have arisen.

00:36:07.860 | But as we're talking about carbon dioxide

00:36:10.040 | over and over again and how key it is to have carbon dioxide

00:36:12.900 | and the problems with it going too high or too low,

00:36:15.620 | you should probably be asking yourself

00:36:17.100 | what actually makes carbon dioxide go too low, right?

00:36:20.000 | We know that we breathe in oxygen

00:36:22.220 | and then it can pass from the lungs

00:36:23.860 | and the avioli into the bloodstream

00:36:25.620 | and then we need carbon dioxide to liberate oxygen

00:36:27.980 | from the hemoglobin into the cells and tissues of the body.

00:36:30.800 | And we know that when we exhale,

00:36:33.340 | or actually I haven't told you this yet,

00:36:35.180 | but you should know that when you exhale,

00:36:37.260 | carbon dioxide is actually taken from the bloodstream

00:36:39.980 | back into those avioli of the lungs.

00:36:42.620 | And then when you exhale, it's expelled through your mouth

00:36:45.520 | or through your nose out into the world.

00:36:47.260 | So the way I just described all that,

00:36:48.920 | inhale, bring in oxygen, exhale, expel carbon dioxide,

00:36:53.020 | pretty straightforward, right?

00:36:56.280 | Indeed it is.

00:36:57.420 | And it also tells you that were you to exhale a lot more

00:37:01.920 | or a lot more vigorously,

00:37:03.500 | you would expel more carbon dioxide.

00:37:06.580 | And in fact, that's exactly the way it works.

00:37:08.520 | When you hyperventilate,

00:37:10.660 | of course you are inhaling more than usual,

00:37:13.420 | but you are also exhaling more than usual.

00:37:15.460 | So you're of course bringing in more air

00:37:17.220 | and oxygen to your body,

00:37:18.700 | but you're also removing more carbon dioxide

00:37:21.360 | from your body than normal.

00:37:22.760 | Carbon dioxide because of the ways

00:37:25.600 | that it regulates brain state,

00:37:27.280 | in fact, the way in which it regulates the excitability,

00:37:31.180 | literally the ability of your neurons

00:37:32.760 | to engage electrically or not,

00:37:35.720 | it can create states of panic and anxiety,

00:37:40.160 | which is why when you hyperventilate,

00:37:42.740 | you feel an increase in anxiety,

00:37:45.240 | or when you feel an increase in anxiety, you hyperventilate.

00:37:48.180 | It's a reciprocal relationship.

00:37:49.780 | In fact, I don't want anyone who has anxiety

00:37:53.020 | or who has panic attacks to try this now,

00:37:55.340 | but for most people, it's probably safe

00:37:57.060 | as long as you're not driving

00:37:58.020 | or doing something mechanical or operating machinery,

00:38:00.840 | that is probably safe to do 25 or 30 deep inhales and exhales.

00:38:05.500 | And you'll notice that by about breath 10,

00:38:08.300 | you'll start to feel tingly

00:38:09.920 | and you'll probably feel a little bit more alert.

00:38:12.060 | And again, if you have anxiety or panic attack tendencies,

00:38:16.180 | please don't do this,

00:38:17.400 | but you will feel an increase in so-called autonomic arousal

00:38:20.940 | and increase in the activity

00:38:22.080 | of your overall sympathetic nervous system,

00:38:23.860 | which has nothing to do with sympathy,

00:38:24.980 | has everything to do with alertness.

00:38:26.420 | You'll actually deploy adrenaline from your adrenals.

00:38:29.340 | So I'll just do this now.

00:38:30.260 | You can try this now, again,

00:38:31.400 | provided you're in a safe place

00:38:32.820 | and you don't have anxiety or panic attack tendencies.

00:38:35.240 | You will just breathe in through your nose

00:38:36.460 | and out through your mouth.

00:38:37.280 | Remember, we're breathing in more and more vigorously

00:38:39.340 | and we're exhaling more and more vigorously

00:38:41.300 | than we normally would.

00:38:42.140 | It goes something like this.

00:38:42.980 | [inhales and exhales]

00:38:46.720 | [inhales and exhales]

00:38:48.400 | Now, by breath eight or nine or 10,

00:38:50.580 | you'll notice that your body starts to heat up.

00:38:53.380 | That's due to a couple of things,

00:38:55.560 | mainly the release of adrenaline from your adrenals.

00:38:57.540 | I'm already feeling a little bit lightheaded.

00:38:59.840 | The lightheadedness is actually because your vasculature,

00:39:03.400 | the capillaries and veins,

00:39:04.620 | and to some extent even the arteries of your body

00:39:07.000 | and particularly in your brain

00:39:08.080 | are actually starting to constrict.

00:39:09.560 | So you're cutting off blood flow to the brain.

00:39:12.080 | Why?

00:39:12.960 | Well, because carbon dioxide actually is a vasodilator.

00:39:17.280 | Normally it exists in your body

00:39:19.540 | to keep capillaries, veins, and arteries dilated

00:39:22.860 | to allow blood to pass through them.

00:39:24.100 | When you hyperventilate,

00:39:25.220 | sure, you're bringing in a lot of oxygen,

00:39:26.940 | which you think would make you more alert,

00:39:28.300 | and indeed it does,

00:39:29.460 | but you are also expelling a lot more carbon dioxide

00:39:32.660 | than you normally would,

00:39:33.620 | and that's causing some vasoconstriction,

00:39:35.740 | and you're going to start feeling tingly in the periphery

00:39:37.980 | in your fingers and toes, perhaps, or your legs.

00:39:40.980 | You will also notice that you're feeling more alert

00:39:42.780 | in the brain,

00:39:43.620 | but that you might start to feel a bit of anxiety.

00:39:45.960 | So hyperventilation, yes, brings in more oxygen,

00:39:48.240 | also removes more carbon dioxide.

00:39:50.680 | The removal of excess carbon dioxide puts you into a state

00:39:54.020 | that's called hypokapnic, all right?

00:39:56.260 | Hypoxia, hypoxia is reduced levels of oxygen

00:40:00.760 | relative to normal.

00:40:02.000 | Hypokapnia is reduced levels of carbon dioxide

00:40:05.340 | relative to normal,

00:40:06.580 | and it is those reduced levels of carbon dioxide

00:40:09.240 | that are largely responsible for that elevation in energy

00:40:12.180 | and at the same time, a feeling of a bit of anxiety,

00:40:14.640 | the constriction of the microvasculature

00:40:17.220 | in the brain and body,

00:40:18.460 | and therefore the feelings of being kind of tingly

00:40:21.220 | and having kind of an urgency to move.

00:40:23.460 | Okay, so by now it should be clear

00:40:25.260 | that we need both oxygen and carbon dioxide,

00:40:28.780 | and across the course of this episode,

00:40:30.140 | I will explain how to adjust those ratios

00:40:32.260 | of oxygen to carbon dioxide,

00:40:34.200 | depending on what your immediate needs are

00:40:37.020 | and what you plan to do next,

00:40:39.400 | whether or not that's sleep or exercise

00:40:41.500 | or some mental work, et cetera.

00:40:43.560 | Before going any further, however,

00:40:45.400 | there is something I want to touch on

00:40:46.580 | because even though not everyone will experience this,

00:40:49.500 | I think enough people experience it

00:40:51.740 | that it is of interest and now's the right time

00:40:54.320 | to touch into what happens

00:40:56.220 | when you go up to a very high altitude,

00:40:58.980 | meaning why it's hard to breathe

00:41:01.620 | when you get up to high altitudes.

00:41:03.420 | So if you're close to sea level,

00:41:05.500 | you are getting kind of the optimal balance

00:41:08.460 | of oxygen in the air you breathe.

00:41:10.760 | As you ascend in altitude,

00:41:12.340 | so let's say you go to 6,000 feet or 10,000,

00:41:15.860 | or maybe even 11,000 feet above sea level,

00:41:17.860 | or maybe you're one of those rare individuals

00:41:19.820 | that climbs Denali or you climb Mount Everest

00:41:24.500 | and you get up there and you notice that, you know,

00:41:25.900 | most people are going to wear an oxygen mask.

00:41:28.620 | Why is it that you need an oxygen mask

00:41:32.800 | at those very high altitudes?

00:41:34.000 | Or when people do these very high altitude skydives

00:41:36.900 | that they need oxygen way up high?

00:41:39.460 | Well, a lot of people will say,

00:41:40.360 | oh, there's not much oxygen up there.

00:41:42.100 | You know, the air is thinner.

00:41:43.660 | Okay, well, perhaps a better way to think about it

00:41:46.300 | is that remember when we were talking

00:41:47.540 | about the mechanical aspects of breathing

00:41:50.580 | and the fact that the lungs don't really move themselves,

00:41:53.600 | that they have the muscles, the diaphragm

00:41:54.940 | and the intercostal muscles to move them?

00:41:56.780 | Well, a lot of the reason why your lungs

00:41:59.340 | can fill so readily with air

00:42:01.660 | is that when you don't have much air in your lungs,

00:42:05.700 | there's very low air pressure in your lungs

00:42:08.840 | relative to outside you, okay?

00:42:11.920 | So what we mean then is if you were to open up your mouth

00:42:15.920 | or your nose and breathe in,

00:42:17.780 | that is breathe in through your nose or mouth,

00:42:20.060 | what's going to happen is air is going to move

00:42:22.800 | from high pressure to low pressure.

00:42:24.300 | So it's very easy to fill your lungs.

00:42:25.780 | Even though you need those muscles

00:42:26.980 | to move the various things around

00:42:28.900 | that allow your lungs to fill,

00:42:30.420 | the air is going to go from high pressure to low pressure.

00:42:33.020 | So for those of you listening,

00:42:35.420 | I just took a big inhale through my nose.

00:42:38.160 | And then when you exhale, right,

00:42:39.780 | you're basically taking the lungs from a state

00:42:41.620 | in which the pressure is really high in the lungs,

00:42:43.460 | high pressure, like a balloon that's full,

00:42:45.700 | and the pressure in your lungs when your lungs are full

00:42:49.200 | is higher than the air outside.

00:42:50.680 | So it's pretty easy to expel that air

00:42:53.460 | through the nose or mouth.

00:42:55.000 | When you're at high altitudes, the air pressure is lower.

00:42:59.220 | And so what happens is when the air pressure

00:43:01.380 | is lower outside your body

00:43:03.740 | and your lungs are not full of air,

00:43:06.600 | you don't have that really steep gradient

00:43:08.460 | of high pressure outside the body

00:43:09.880 | to low pressure inside your lungs.

00:43:11.820 | And so you actually have to put a lot more effort

00:43:14.740 | into breathing air into your lungs.

00:43:17.160 | You have to really exert a lot of force.

00:43:19.020 | You have to get the diaphragm,

00:43:20.380 | those intercostal muscles working really hard.

00:43:22.220 | You might even find that your shoulders

00:43:23.580 | are lifting with each breath

00:43:25.020 | 'cause you really have to generate a lot of force

00:43:26.660 | to get enough air and oxygen into your lungs.

00:43:30.180 | Now, an important principle to understand

00:43:31.660 | is that in humans and in some other species,

00:43:34.340 | but really what we're talking about now as humans,

00:43:37.180 | when you inhale, that's an active process.

00:43:39.500 | You really need to use those muscles of the intercostals

00:43:42.420 | and the diaphragm in order to inflate the lungs.

00:43:45.000 | But the whole process is made easier

00:43:47.380 | when air pressure outside your body is higher

00:43:50.160 | than it is in your lungs

00:43:51.120 | because then they're going to fill up really readily.

00:43:53.840 | Exhaling, at least for humans, is a passive thing.

00:43:57.920 | You just have to relax the diaphragm

00:43:59.640 | and relax the intercostals and let the rib cage

00:44:01.820 | kind of fall back to its original position.

00:44:04.540 | So inhaling is active and exhaling is passive.

00:44:07.380 | And so what happens is if you're at a high altitude

00:44:10.140 | and the air pressure is very low,

00:44:12.020 | then you have to put a lot of energy

00:44:14.020 | into breathing air into your lungs

00:44:16.020 | to get an equivalent amount of oxygen into your lungs

00:44:19.040 | and then into the bloodstream.

00:44:20.500 | So that's why when you arrive at a high altitude location,

00:44:23.120 | for the first few days, you're going to feel lightheaded,

00:44:24.900 | maybe a headache.

00:44:26.200 | You're also going to have more buildup

00:44:27.180 | of carbon dioxide in your system.

00:44:28.900 | And so the whole balance of oxygen and carbon dioxide

00:44:32.060 | is going to be disrupted.

00:44:33.660 | I mention all that because yes, indeed,

00:44:36.260 | there are some changes in the atmospheric gases

00:44:38.220 | at high altitudes and that can impact

00:44:41.140 | how much oxygen you can bring into your system,

00:44:42.820 | into your tissues.

00:44:43.860 | But I've heard many explanations of why it's hard to breathe

00:44:46.900 | or why you feel lousy at altitude.

00:44:49.100 | Well, you just discovered one reason,

00:44:50.920 | which is that you don't have that steep high pressure

00:44:52.880 | to low pressure gradient from the outside of the body

00:44:54.820 | into the inside of the body.

00:44:57.120 | The converse is also true.

00:44:58.260 | If you've been at altitude for a few days

00:44:59.940 | and you've had the opportunity to adjust,

00:45:01.500 | a lot of athletes, for instance, will go train at altitude.

00:45:04.660 | It's hard for them in the first days or weeks,

00:45:06.580 | and then they get really good at training at altitude.

00:45:08.900 | There are a number of different adaptations that occur

00:45:11.660 | in terms of the amount of oxygen

00:45:13.220 | that can be carried in the blood by hemoglobin

00:45:15.680 | and the interactions between carbon dioxide

00:45:17.480 | and hemoglobin and oxygen that allow more oxygen

00:45:20.080 | to be delivered to the tissues such that at altitude,

00:45:23.980 | you can function just normally.

00:45:25.740 | But if you then move very quickly from altitude,

00:45:28.660 | say you've been training at 8,000 feet or 10,000 feet,

00:45:31.020 | you've been hiking up at the high level and you've adapted,

00:45:32.940 | and you come down to sea level,

00:45:34.900 | well, for about two to five days,

00:45:36.980 | you're going to feel like an absolute beast.

00:45:39.500 | You're going to be able to essentially deliver

00:45:42.140 | far more oxygen to your muscles per breath.

00:45:45.380 | In part, that is because of the way that the hemoglobin

00:45:48.740 | and the oxygen that it's carrying has been altered

00:45:51.200 | when you were at high altitude.

00:45:52.160 | But it's also because when you were at that high altitude,

00:45:55.560 | those intracostal muscles and those diaphragms

00:45:57.740 | got trained up quite a bit and allowed you

00:46:00.760 | to generate more air volume for every breath.

00:46:03.640 | In other words, those muscles got stronger

00:46:05.280 | and you got more efficient at driving the phrenic nerve

00:46:07.940 | consciously to really breathe in a lot of oxygen

00:46:10.620 | so you don't feel lightheaded, headache, et cetera.

00:46:12.840 | Okay, so that's a little bit of an aside,

00:46:14.300 | but it's an important aside, I believe,

00:46:16.020 | because A, it answers a question a lot of people ask

00:46:19.080 | and a lot of people wonder about,

00:46:20.640 | and B, because it incorporates

00:46:22.520 | both the mechanical aspects of breathing

00:46:24.200 | and the chemical aspects of breathing.

00:46:26.040 | I realize it's a little bit of a unusual circumstance,

00:46:28.820 | but now if anyone asks you

00:46:29.940 | why it's hard to breathe at altitude,

00:46:31.200 | you know it has to do with this lack of a high pressure

00:46:33.160 | to low pressure gradient across the body

00:46:35.800 | and with the atmosphere outside you.

00:46:37.480 | It's also an opportunity for me to say

00:46:39.080 | that if you do find yourself at altitude

00:46:40.640 | and you have a headache

00:46:41.720 | or you're feeling like you just can't catch your breath,

00:46:43.920 | spending some time really consciously

00:46:45.480 | trying to draw in larger breaths of air,

00:46:47.960 | as much as that might seem fatiguing

00:46:49.680 | and you'll be short of breath,

00:46:50.800 | it will allow you to adapt more quickly.

00:46:52.560 | And a little bit later in the episode,

00:46:53.680 | we'll touch on a few methods,

00:46:54.860 | including deliberate hyperventilation

00:46:56.840 | combined with some breath holds

00:46:57.840 | that can allow you to deliver more oxygen to the cells

00:47:00.160 | immediately upon arriving at altitude

00:47:02.200 | so you don't get quite as much headache,

00:47:03.480 | disorientation and so on.

00:47:05.300 | So leaving breathing at altitude aside,

00:47:07.680 | let's all come back down to the same conceptual level.

00:47:10.820 | We can ask ourselves for instance,

00:47:14.180 | what is healthy breathing and what is unhealthy breathing?

00:47:17.080 | And the first place we want to tackle this

00:47:19.200 | is within the context of sleep.

00:47:21.500 | So when we go to sleep at night,

00:47:22.920 | we continue to breathe, that's no surprise.

00:47:25.200 | If we didn't, we would die during sleep.

00:47:27.400 | However, there is a large fraction of the population

00:47:30.620 | that underbreathes during sleep.

00:47:32.620 | They're not taking deep enough or frequent enough breaths

00:47:36.440 | and therefore they are experiencing

00:47:38.520 | what's called sleep apnea.

00:47:39.840 | They are becoming hypoxic, hypoxic.

00:47:43.160 | There's less oxygen being brought into their system

00:47:45.920 | than is necessary.

00:47:47.040 | People that are carrying excess weight,

00:47:49.160 | either fat weight or muscle weight or both

00:47:52.000 | are more prone to nighttime sleep apnea.

00:47:55.320 | However, there are a lot of people who are not overweight

00:47:58.000 | who also experience sleep apnea.

00:47:59.920 | How do you know if you're experiencing sleep apnea?

00:48:02.200 | Well, first of all, excessive daytime sleepiness

00:48:04.660 | and excessive daytime anxiety

00:48:06.320 | combined with daytime sleepiness

00:48:08.000 | is one sign that you might be suffering from sleep apnea.

00:48:11.040 | The other thing is if you happen to snore,

00:48:13.440 | it's very likely that you are experiencing sleep apnea.

00:48:16.840 | And I should mention that sleep apnea

00:48:18.320 | is a very serious health concern.

00:48:20.360 | It greatly increases the probability

00:48:22.560 | of a cardiovascular event, heart attack, stroke.

00:48:26.280 | It is a precursor or sometimes the direct cause

00:48:29.280 | of sexual dysfunction in males and females,

00:48:31.860 | cognitive dysfunction during the daytime.

00:48:34.080 | It can exacerbate the effects of dementia,

00:48:37.560 | whether or not it's age-related,

00:48:39.060 | dementia of the normal sort or Alzheimer's type dementia,

00:48:41.960 | which is an acceleration of age-related cognitive decline.

00:48:44.960 | If you're somebody who's had a traumatic brain injury,

00:48:47.760 | if you're experiencing a lot of stress,

00:48:49.160 | sleep apnea is going to greatly disrupt

00:48:51.400 | the amount of oxygen brought into your brain

00:48:52.960 | and body during sleep and is going to lead

00:48:55.240 | to a number of nighttime and daytime issues.

00:48:58.280 | So it's something that really needs to be addressed.

00:49:00.180 | And we'll get into this a bit more later,

00:49:02.020 | but since I raised it as a problem,

00:49:03.840 | I do want to raise the solution.

00:49:05.200 | One of the major treatments for sleep apnea

00:49:08.040 | is that people will get a CPAP device,

00:49:09.660 | which is this face mask and a machine

00:49:12.580 | that they'll sleep with.

00:49:13.420 | And while those can be very effective,

00:49:15.240 | not everyone needs a CPAP.

00:49:16.820 | One of the more common methods nowadays

00:49:19.040 | that's being used to treat sleep apnea,

00:49:20.720 | which is purely behavioral and intervention

00:49:23.200 | and is essentially zero cost,

00:49:24.680 | is that people are starting to shift deliberately

00:49:27.340 | to nasal breathing during sleep

00:49:29.640 | because of the additional resistance of nasal breathing

00:49:32.600 | and because of the fact that there's far less tendency,

00:49:35.140 | if any, excuse me, to snore when nasal breathing.

00:49:39.140 | Taping the mouth shut using medical tape prior to sleep,

00:49:42.760 | excuse me, putting medical tape on the mouth

00:49:45.200 | prior to going to sleep and then sleeping all night

00:49:48.180 | with medical tape on the mouth

00:49:49.380 | is one way that people can learn to nasal breathe

00:49:51.620 | during sleep and can greatly offset a lot of sleep apnea,

00:49:55.240 | snoring and sleep-related issues.

00:49:57.780 | A number of people don't want to or don't feel safe

00:50:00.320 | putting medical tape on their mouth prior to sleep.

00:50:02.560 | For some reason, they think they're going to suffocate,

00:50:04.180 | but of course you would wake up

00:50:05.180 | if you start to run out of air at any moment.

00:50:08.280 | So that's not so much a concern.

00:50:09.900 | But what they'll do is they will start to use

00:50:12.380 | pure nasal breathing during any type of exercise

00:50:15.500 | or even just for some period of time,

00:50:17.140 | walking during the day or while working.

00:50:19.460 | And again, later, we'll get into the enormous benefits

00:50:22.260 | of shifting to pure nasal breathing

00:50:24.460 | when not exercising hard,

00:50:27.060 | meaning at a rate that you could normally

00:50:29.240 | hold a conversation.

00:50:30.180 | Although if you're pure nasal breathing,

00:50:31.820 | you won't be holding that conversation.

00:50:33.620 | Or when simply doing work or any number of things

00:50:38.100 | that are sort of low intensity,

00:50:39.840 | you can train your system to become a better nasal breather

00:50:42.460 | during the daytime through these deliberate actions

00:50:44.700 | of taping the mouth shut or just being conscious

00:50:46.280 | of keeping your mouth shut.

00:50:47.360 | And that in addition to having a number of positive health

00:50:50.080 | and aesthetic effects during the daytime

00:50:52.400 | is known to also transfer to nighttime breathing patterns

00:50:55.840 | and allow people to become nasal breathers

00:50:58.380 | as opposed to mouth breathers during sleep

00:51:00.580 | and to snore less and to have less sleep apnea.

00:51:02.980 | Again, if you have severe sleep apnea,

00:51:04.620 | you probably do need to check out a CPAP.

00:51:07.800 | You should talk to your physician.

00:51:09.280 | But for people who have minor sleep apnea or sleep apnea

00:51:12.420 | that's starting to take hold,

00:51:15.200 | these other methods of shifting to becoming a nasal breather

00:51:18.260 | are going to be far more beneficial

00:51:19.880 | and far more cost effective

00:51:21.560 | than going all the way to the CPAP.

00:51:23.020 | Which by the way, doesn't really teach you

00:51:25.320 | how to breathe properly as much as it does

00:51:27.660 | adjust the airflow going into your system.

00:51:30.540 | That's an important point.

00:51:31.780 | Then when you shift from mouth to nasal breathing

00:51:33.740 | during sleep, you're actually learning

00:51:35.660 | and training your system to breathe properly.

00:51:37.820 | And when I say learning and training your system

00:51:39.840 | to breathe properly, what do I mean?

00:51:41.660 | Let's put some scientific and mechanistic meat on that.

00:51:44.900 | We already talked about the phrenic nerve,

00:51:46.460 | this nerve that innervates the diaphragm

00:51:48.080 | and that allows for the lungs to fill up

00:51:50.300 | because of the movement of the diaphragm.

00:51:51.960 | What we didn't talk about, however,

00:51:53.820 | were the brain centers that actually control

00:51:55.800 | the phrenic nerve and control breathing.

00:51:58.020 | Knowing about these two brain areas

00:51:59.500 | and what they do is extremely important,

00:52:01.840 | not just for understanding the content of this episode,

00:52:04.420 | but for understanding all of the tools that we'll discuss

00:52:06.940 | and indeed your general health as it relates to respiration.

00:52:10.280 | So there are basically two areas of the brain

00:52:12.340 | that control breathing.

00:52:13.500 | The first is called the pre-buttsinger complex.

00:52:15.680 | You don't have to worry about the name so much,

00:52:17.040 | just know that it was named after a bottle of wine

00:52:18.820 | and that it was discovered by the great Jack Feldman,

00:52:22.200 | who's a professor of neuroscience

00:52:24.300 | at the University of California, Los Angeles.

00:52:26.380 | This is one of the most fundamental discoveries

00:52:28.020 | in all of neuroscience in the last 100 years or more

00:52:31.060 | because this brain area that Jack and his colleagues

00:52:33.300 | discovered controls all aspects of breathing

00:52:36.140 | that are rhythmic.

00:52:37.220 | That is when inhales follow exhales,

00:52:40.020 | follow inhales follow exhales.

00:52:42.220 | That's all controlled by a small set of neurons

00:52:44.740 | in this brainstem area,

00:52:46.320 | so around the region of the neck

00:52:49.180 | called the pre-buttsinger complex.

00:52:50.940 | And we really owe a debt of gratitude to Jack

00:52:53.860 | and his colleagues for discovering that area

00:52:55.900 | because it's involved in everything

00:52:57.580 | from breathing when we're asleep

00:52:59.420 | to breathing when we're not thinking about our breathing.

00:53:01.780 | It may have a role,

00:53:03.620 | that is when its function is disrupted,

00:53:06.280 | it may cause things like sudden infant death syndrome.

00:53:09.300 | Believe it or not, it can explain in large part

00:53:12.700 | many of the deaths related to the opioid crisis

00:53:15.900 | because exogenous opioids like fentanyl

00:53:18.340 | and other sorts of drugs, which are opioids obviously,

00:53:21.700 | bind to opioid receptors on that structure

00:53:25.260 | and shut it down.

00:53:27.100 | Now, keep in mind,

00:53:28.100 | these neurons are designed to be incredibly robust

00:53:30.740 | and are designed to fire, inhale, exhale, inhale, exhale,

00:53:33.860 | no matter if we're awake or aware,

00:53:36.100 | unaware or asleep to keep us alive.

00:53:39.300 | Exogenous opioids like fentanyl

00:53:42.320 | and drugs that are similar to that

00:53:44.420 | can shut down that structure

00:53:46.040 | because it's rich with these opioid receptors,

00:53:48.500 | so it binds to that

00:53:49.380 | and it shuts off the pre-buttsinger complex,

00:53:51.300 | which is the major cause of death

00:53:52.620 | of people who die from opioid overdoses.

00:53:55.220 | I think a lot of people don't realize that.

00:53:56.380 | They think, oh, the opioids must shut off the brain

00:53:58.340 | or shut down the heart.

00:53:59.420 | No, it shuts down breathing.

00:54:01.420 | So Jack's discovery, no doubt,

00:54:03.260 | will lead to some important things

00:54:05.260 | as it relates to addiction.

00:54:06.840 | And hopefully, I think we frankly can expect

00:54:09.780 | that it's also going to eventually lead to ways

00:54:12.300 | to prevent death in people using opioids

00:54:15.640 | or other types of drugs,

00:54:16.580 | maybe by blocking opioid receptors

00:54:18.760 | in pre-buttsinger complex

00:54:20.100 | using things like naltrexone, et cetera.

00:54:22.340 | In any event, pre-buttsinger complex

00:54:23.960 | is controlling inhale, exhale, inhale, exhale

00:54:26.300 | to patterns of breathing.

00:54:27.540 | The other brain center controlling breathing,

00:54:29.780 | again, through the phrenic nerve, right?

00:54:31.660 | It all converges and goes out through the phrenic nerve

00:54:33.500 | in these intercostal muscles.

00:54:35.180 | Is the so-called parafacial nucleus.

00:54:36.980 | And the parafacial nucleus is involved

00:54:38.680 | in patterns of breathing

00:54:40.300 | where there is not an inhale followed by exhale,

00:54:44.660 | inhale followed by exhale.

00:54:45.640 | That is, it's not rhythmic one than the other,

00:54:48.140 | but rather where there is a doubling up of inhales

00:54:50.600 | or a doubling up of exhales

00:54:52.020 | or a deliberate pause in breathing.

00:54:54.020 | So inhale, pause, exhale, pause, inhale, pause, exhale,

00:54:57.660 | pause, this sort of thing.

00:54:59.080 | A little bit later,

00:54:59.920 | we'll talk about a pattern of breathing

00:55:01.220 | called box breathing,

00:55:02.120 | which has a very specific and useful applications,

00:55:05.720 | in particular for adjusting anxiety.

00:55:09.320 | And in that case,

00:55:10.680 | it involves going from rhythmic breathing of inhale,

00:55:13.080 | inhale, inhale, exhale,

00:55:15.160 | that is relying on the pre-Buttsinger complex neurons

00:55:18.640 | to reliance on the parafacial nucleus neurons

00:55:22.280 | and box breathing,

00:55:23.140 | just to give away what's probably already obvious

00:55:24.960 | is you inhale, hold, exhale, hold, and repeat.

00:55:28.360 | And that pattern of breathing,

00:55:29.720 | even though it's rhythmic in nature

00:55:31.400 | because inhales precede exhales, precede inhales, and so on,

00:55:34.700 | there's a deliberate breath hold inserted there.

00:55:36.800 | So anytime we're taking conscious control of our breathing,

00:55:39.760 | the parafacial nucleus is getting involved.

00:55:42.840 | Now you don't have to assume that the parafacial nucleus

00:55:45.880 | is the only way in which we take conscious control

00:55:48.280 | of our breathing.

00:55:49.100 | We can also take control of the pre-Buttsinger complex.

00:55:51.400 | You can do that right now.

00:55:52.400 | So for instance,

00:55:53.220 | you are breathing in some specific pattern now

00:55:54.980 | that unless you're speaking or eating,

00:55:57.280 | no doubt is going to involve inhales followed by exhales.

00:56:00.000 | You could, for instance, decide that,

00:56:02.320 | yes, inhales are active and exhales are passive,

00:56:05.840 | but now you're going to make the exhales active as well.

00:56:08.480 | So rather than just inhale and then let your lungs deflate,

00:56:11.480 | you could inhale and then force the air out.

00:56:14.740 | That's going to represent a conscious taking over of control

00:56:17.820 | of the pre-Buttsinger complex.

00:56:19.480 | Okay, so the reason I'm giving this mechanistic detail is,

00:56:22.980 | A, it's super important if you want to understand

00:56:25.700 | all the tools related to breathing.

00:56:27.040 | B, it's actually a pretty simple system,

00:56:29.060 | even though the areas have fancy names

00:56:31.260 | like pre-Buttsinger or parafacial,

00:56:33.080 | it's pretty straightforward, right?

00:56:34.200 | You have one area that controls rhythmic breathing,

00:56:35.880 | inhale follows exhales,

00:56:36.820 | and the other area which gets involved in breathing

00:56:38.940 | anytime you start doubling up on inhales or exhales.

00:56:41.480 | In fact, the parafacial nucleus is the one

00:56:43.120 | that you're relying on while you speak

00:56:45.260 | in order to make sure that you still get enough oxygen.

00:56:47.860 | It's also the one that you will use

00:56:49.120 | if you incorporate the physiological psi or box breathing.

00:56:52.620 | And frankly, most of the time,

00:56:54.400 | you're using both of these circuits or these brain systems,

00:56:57.620 | parafacial and pre-Buttsinger, in parallel.

00:57:00.240 | Again, biology loves parallel systems,

00:57:02.980 | especially for things that are so critical

00:57:05.280 | that if we didn't do them, we would die, like breathing.

00:57:08.080 | And so it makes sense that we have

00:57:09.020 | two different brain structures that control this.

00:57:11.260 | So now you have an understanding

00:57:12.740 | of the mechanical control of breathing,

00:57:15.360 | that is the different parts within the parts list

00:57:18.420 | that are involved in breathing,

00:57:19.420 | everything from nose to mouth to avioli to lungs, et cetera,

00:57:21.880 | and the muscles involved in moving the lungs.

00:57:24.160 | You understand, I like to think a bit

00:57:27.140 | about bringing oxygen in and removing carbon dioxide,

00:57:30.060 | but not so much carbon dioxide

00:57:31.380 | that you can't actually use the oxygen that you have.

00:57:34.340 | And you know about two brain centers,

00:57:37.060 | one controlling rhythmic breathing

00:57:38.580 | and one that controls non-rhythmic breathing.

00:57:41.260 | I want to repeat something

00:57:43.780 | that I said a little bit earlier as well,

00:57:45.300 | which is that breathing is incredible

00:57:47.420 | because it represents the interface

00:57:50.100 | between conscious and subconscious control

00:57:53.080 | over your, not just body, not just your lungs,

00:57:56.880 | but that how you breathe influences your brain state.

00:58:00.320 | So by using your brain consciously

00:58:02.360 | to control your breathing,

00:58:04.060 | you are using your brain to control your brain.

00:58:06.640 | The best way I've ever heard this described

00:58:08.340 | was from a beautiful, I should say now classic paper

00:58:11.340 | in the Journal of Physiology published in 1988

00:58:13.560 | from Ballesterino and Somjan,

00:58:15.460 | where the final line of their summary intro states,

00:58:20.240 | "The brain by regulating breathing

00:58:22.400 | controls its own excitability."

00:58:24.500 | And just to remind those of you

00:58:25.840 | that don't remember what excitability is,

00:58:27.940 | excitability is the threshold at which a given neuron,

00:58:32.400 | nerve cell can be active or not.

00:58:34.180 | So when we breathe a certain way,

00:58:37.180 | the neurons of our brain are more likely to get engaged.

00:58:40.400 | They're more likely to be active.

00:58:41.740 | And when we breathe in other ways,

00:58:43.940 | our brain becomes harder to activate.

00:58:47.140 | Its excitability is reduced.

00:58:49.220 | Now you might think excitability is a great thing.

00:58:51.260 | You always want your brain to be excitable,

00:58:53.080 | but that's actually not the case.

00:58:54.480 | And in fact, that very statement

00:58:57.140 | that Ballesterino and Somjan made

00:58:59.520 | led to a number of other investigations

00:59:01.640 | that were really important in defining how

00:59:04.140 | if people over-breathe,

00:59:06.360 | that is if they hyperventilate at rest,

00:59:09.800 | they expel, that is they exhale too much carbon dioxide.

00:59:14.800 | What that classic paper by Ballesterino and Somjan led to

00:59:18.520 | was a number of different investigations in humans

00:59:21.320 | looking at how different patterns of breathing

00:59:24.360 | impact the overall state of the brain

00:59:26.480 | and the ability of the brain to respond to certain

00:59:29.260 | what are called sensory stimuli.

00:59:31.460 | Keep in mind that your brain is always active.

00:59:34.020 | The neurons are firing at low level, low level, low level.

00:59:37.160 | But when you see something or hear something,

00:59:40.080 | or you want to focus on something,

00:59:41.700 | or you want to exercise or really listen to something

00:59:44.120 | or learn, certain circuits in your brain

00:59:47.080 | need to be more active than everything else.

00:59:49.880 | That is there needs to be really high

00:59:51.360 | what's called signal to noise.

00:59:53.000 | There's always a lot of noise and chatter in the background,

00:59:54.960 | just like the chatter at a cocktail party

00:59:57.220 | or at a stadium event.

00:59:58.920 | In order to really pay attention, focus, learn,

01:00:02.240 | all the incredible things that the brain can do,

01:00:04.220 | you need that signal to get above the noise.

01:00:06.760 | There's a beautiful paper that asks,

01:00:11.200 | how does the pattern of breathing,

01:00:12.940 | in particular, how does over-breathing

01:00:15.200 | change the patterns of activity in the brain?

01:00:19.520 | This is a paper entitled

01:00:20.680 | Effects of Voluntary Hyperventilation on Cortical Sensory

01:00:23.420 | Responses, and I will provide a link to the study

01:00:25.760 | in the show note captions.

01:00:27.160 | It's a somewhat complicated paper

01:00:28.880 | if you look at all the detailed analysis.

01:00:31.640 | However, the takeaway from this paper is exquisitely simple

01:00:35.080 | and I also believe incredibly important.

01:00:37.900 | Basically what it showed is that when people hyperventilate,

01:00:41.160 | they expel, that is they exhale more carbon dioxide

01:00:45.280 | than they would normally.

01:00:46.300 | So they become what's called hypocapnic, okay?

01:00:50.080 | Carbon dioxide levels are low in the blood

01:00:52.920 | and over a short period of time,

01:00:54.640 | they become low in the tissues of the body.

01:00:56.960 | When that carbon dioxide level drops low, you would say,

01:01:02.360 | okay, well, you're still bringing in a lot of oxygen

01:01:04.960 | because these people are hyperventilating,

01:01:07.160 | so they should feel really alert.

01:01:08.760 | And indeed that's what happens, the people feel very alert.

01:01:12.160 | However, because they're not bringing enough

01:01:14.640 | carbon dioxide in, or rather the proper way to say it would

01:01:17.360 | be because they're over-breathing, exhaling too much,

01:01:21.560 | they are not retaining or keeping in enough carbon dioxide.

01:01:26.080 | Well, then that lack of carbon dioxide means that the oxygen

01:01:31.320 | that they are breathing in can't be liberated

01:01:34.360 | from the hemoglobin, can't get to the brain.

01:01:36.880 | And what they observe is about a 30 to 40% reduction

01:01:41.280 | in the amount of oxygen that's being delivered to the brain.

01:01:45.320 | And the reduction in carbon dioxide also prevents

01:01:50.040 | some of the normal patterns of vasodilation,

01:01:52.600 | the dilating, the opening up of the capillaries.

01:01:55.220 | So again, less blood flow, but most importantly,

01:02:00.000 | as it's shown in this paper,

01:02:01.960 | the brain overall becomes hyperexcitable.

01:02:05.560 | It's as if it's being starved of oxygen and blood flow

01:02:08.680 | and all the neurons in a very nonspecific way

01:02:11.980 | start increasing their firing level.

01:02:13.660 | So the background activity is getting louder and louder.

01:02:16.020 | It's like the rumbler, the noise of a crowd at a stadium.

01:02:18.980 | And as a consequence, the sensory input from a sound

01:02:23.980 | or from a touch or from some other event in the world

01:02:28.240 | doesn't get above the noise.

01:02:29.820 | What this means is that when we hyperventilate,

01:02:32.800 | because we aren't retaining enough carbon dioxide,

01:02:36.220 | we are not getting enough oxygen

01:02:37.900 | to the tissues that need oxygen.

01:02:40.520 | And as a consequence of that,

01:02:42.220 | the brain becomes hyperexcitable.

01:02:44.000 | We actually know that there's an increase in anxiety

01:02:47.040 | and we become less good, less efficient

01:02:51.960 | at detecting things in our environment.

01:02:54.520 | So we're not processing information as well at all.

01:02:57.360 | The noise goes up and the signal goes down.

01:02:59.980 | Again, incredibly important set of findings.

01:03:02.280 | I should also mention that hyperventilation is one way

01:03:07.160 | that in the laboratory anyway,

01:03:08.960 | or in neurosurgery units for some time physicians

01:03:13.660 | would evoke seizure in seizure prone patients.

01:03:16.060 | The reason that works is exactly the explanation

01:03:19.380 | I just gave you.

01:03:20.520 | Seizure is a hyperexcitability of the brain,

01:03:22.620 | not enough inhibition or suppression

01:03:24.420 | of the overall circuitry.

01:03:25.500 | So you get these waves or these storms

01:03:27.140 | of electrical activity.

01:03:29.020 | Low levels of carbon dioxide in the brain

01:03:31.800 | because of low levels of carbon dioxide in the blood

01:03:34.620 | are one of the major triggers for seizures.

01:03:37.920 | Now, I realize that most people listening to this

01:03:39.740 | are not epileptic, but nonetheless,

01:03:42.580 | this brings us all back to this question

01:03:44.500 | of what is normal healthy breathing?

01:03:46.180 | As I mentioned before, normal healthy breathing

01:03:47.920 | is breathing about six liters of air per minute.

01:03:51.080 | But of course, most of us don't think

01:03:52.420 | in terms of liters of air

01:03:53.580 | and we're not going to go measure our lung capacity.

01:03:55.300 | At least most of us aren't going to do that.

01:03:57.340 | Basically, if you are taking relatively shallow breaths

01:04:00.600 | and you're just sitting there working

01:04:02.480 | or maybe even walking slowly,

01:04:04.180 | again, not talking or engaging in any kind of speech

01:04:06.780 | or eating, chances are six liters of air per minute

01:04:11.780 | is about 12 shallow-ish breaths.

01:04:14.960 | And when I say shallow, I don't mean breathing

01:04:18.240 | like a little bunny rabbit or something like that.

01:04:19.780 | I just mean casually breathing in, out, in, out.

01:04:22.940 | The studies that have explored the breathing patterns

01:04:26.780 | in large populations of individuals

01:04:30.360 | who are not suffering necessarily

01:04:32.040 | from any one specific ailment

01:04:35.300 | have shown that most people breathe far too much per minute,

01:04:39.920 | that they're engaging in anywhere from 15 to 20

01:04:43.020 | or even 30 shallow breaths per minute.

01:04:45.380 | So they are vastly over-breathing

01:04:48.200 | relative to how they should be breathing.

01:04:50.220 | Now, of course, if you breathe more deeply,

01:04:52.380 | so you take a vigorous inhale,

01:04:54.040 | and then you expel that air,

01:04:58.140 | well, then to get six liters of air

01:05:00.260 | into your system per minute,

01:05:02.060 | you're probably only going to need

01:05:03.940 | somewhere between four and six breaths

01:05:08.520 | in order to get that six liters per minute.

01:05:11.020 | Now, the total time that it takes to do that inhale and exhale

01:05:14.780 | isn't that much longer than a kind of shallow breath,

01:05:17.880 | provided you're not deliberately breathing quickly

01:05:19.780 | during those shallow breaths.

01:05:21.340 | So then you say, well,

01:05:22.700 | how is it that normal healthy breathing

01:05:25.020 | that delivers the appropriate amount of carbon dioxide

01:05:27.920 | into the system and doesn't expel,

01:05:30.420 | doesn't exhale too much carbon dioxide,

01:05:32.700 | how are we supposed to do that normal breathing, right?

01:05:34.500 | Are you supposed to breathe four times

01:05:35.780 | and then hold your breath until the minute passes?

01:05:37.420 | No, what you find is that the correct pattern of breathing

01:05:41.340 | is going to involve two things.

01:05:42.580 | First of all, nasal breathing,

01:05:43.860 | because of the resistance it provides through the nose

01:05:45.940 | that we talked about earlier,

01:05:46.900 | is going to deliver more oxygen into your system.

01:05:49.300 | You're going to be able to generate more air pressure

01:05:51.420 | to fill your lungs.

01:05:52.900 | That greater air pressure is going to take longer to exhale.

01:05:57.900 | So already we're increasing the amount of time

01:05:59.640 | that each breath is going to take.

01:06:01.300 | And also what you find is that people that are breathing

01:06:04.100 | in the proper healthy manner,

01:06:05.500 | that is that are balancing oxygen and carbon dioxide

01:06:07.860 | in the proper ways,

01:06:09.320 | are also taking pauses between breaths.

01:06:12.540 | This is extremely important

01:06:13.660 | because even though we have a brain center,

01:06:15.260 | the pre-Botzinger complex that can control,

01:06:18.340 | or I should say does control inhale, exhale,

01:06:20.360 | rhythmic breathing,

01:06:21.660 | those pauses between breaths are not always present.

01:06:25.500 | In fact, often are not present

01:06:27.460 | from people's baseline breathing patterns

01:06:29.340 | and as a consequence, they over-breathe.

01:06:31.780 | And as I told you before, when people over-breathe,

01:06:34.160 | their brain becomes hyperexcitable

01:06:35.940 | at the level of the background noise,

01:06:37.500 | and yet they are less efficient

01:06:39.840 | at detecting and learning information.

01:06:42.300 | And we'll get into the specific studies

01:06:43.540 | that really illustrate the learning aspect a bit later,

01:06:46.080 | but they are less efficient

01:06:48.340 | at detecting and learning information,

01:06:50.140 | at focusing and so on,

01:06:52.000 | as a consequence of this over-breathing

01:06:54.900 | and the hyperexcitability that causes.

01:06:57.180 | Now, of course, that's also just emphasizing

01:07:00.340 | the effects of over-breathing

01:07:02.060 | and lack of carbon dioxide on the brain.

01:07:04.260 | There are hundreds, if not thousands of studies

01:07:07.500 | showing that when we don't have enough carbon dioxide

01:07:09.700 | in the tissues of our body,

01:07:10.880 | that's also problematic for all the tissues,

01:07:12.900 | the liver, the lungs themselves, the stomach, et cetera,

01:07:16.620 | that relate largely to shifts in pH

01:07:19.800 | because of the fact that carbon dioxide

01:07:22.500 | strongly regulates the acidity, alkalinity of the blood

01:07:25.760 | and the tissues that that blood supplies nutrients to,

01:07:29.060 | including carbon dioxide.

01:07:30.580 | So the basic takeaway here is

01:07:33.020 | you want to breathe in a healthy manner at rest.

01:07:35.680 | And the best way to do that is to spend some time,

01:07:39.100 | and it doesn't take much, maybe a minute or so each day,

01:07:42.200 | paying attention to how quickly you are breathing per minute

01:07:46.560 | when you are simply at rest,

01:07:47.980 | when you're making coffee in the morning,

01:07:49.780 | when you're sitting down to read,

01:07:51.180 | when you're on social media.

01:07:52.600 | Chronically holding your breath isn't good,

01:07:55.420 | but neither is over-breathing.

01:07:57.100 | And again, every study that has examined

01:08:00.800 | the typical patterns of breathing

01:08:02.440 | and patterns of breathing that show up as normal

01:08:04.980 | and abnormal has found that more often than not,

01:08:07.360 | during the nighttime, people are under-breathing,

01:08:10.420 | and in the daytime, they are over-breathing,

01:08:12.880 | they're hyperventilating.

01:08:14.400 | I'd like to just take a brief moment

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01:09:32.040 | So next I'd like to address what you can do

01:09:33.860 | about your normal patterns of breathing.

01:09:35.280 | That is how you or anyone can adjust their normal patterns

01:09:38.840 | of breathing from an unhealthy to an unhealthy state.

01:09:41.800 | But the first thing we have to do, of course,

01:09:43.060 | is determine whether or not you're already breathing

01:09:45.240 | in an unhealthy or in a healthy way.

01:09:47.700 | And again, when I say healthy or unhealthy,

01:09:49.200 | I mean, are you over-breathing?

01:09:51.280 | Are you under-breathing?

01:09:52.200 | Are you delivering the appropriate ratios

01:09:53.880 | of oxygen and carbon dioxide

01:09:55.560 | to the tissues of your brain and body?

01:09:57.760 | In order to do this, we're going to do a simple test.

01:10:00.560 | Again, please don't do this while driving

01:10:02.880 | or operating heavy machinery or near water of any kind,

01:10:07.280 | but assuming that you're not doing any of those things,

01:10:10.280 | I encourage you to sit down,

01:10:12.600 | certainly not lie down, but just sit down.

01:10:15.000 | I suppose you also could do it standing,

01:10:16.280 | and we are going to do what's called

01:10:17.980 | the carbon dioxide tolerance test.

01:10:20.480 | The carbon dioxide tolerance test

01:10:21.820 | is a sort of back of the envelope measure

01:10:24.200 | of how well you are managing carbon dioxide.

01:10:27.240 | That is how well you can control your breathing

01:10:30.140 | at both the mechanical and the chemical level.

01:10:33.480 | It's a very simple test.

01:10:34.800 | What you're going to do is for the next 10 seconds or so

01:10:37.800 | while I'm speaking, you're just going to breathe normally.

01:10:40.640 | Now, again and again, throughout this episode,

01:10:43.060 | I'm going to encourage you to be a nasal breather

01:10:46.000 | whenever possible.

01:10:47.280 | But of course, there are instances

01:10:49.440 | in which you want to engage mouth breathing.

01:10:51.880 | But for the time being, as I continue to blab on

01:10:54.280 | for the next few seconds, just inhale through your nose,

01:10:58.520 | exhale through your nose.

01:10:59.580 | You don't have to deliberately slow your breathing

01:11:01.560 | or increase the cadence of your breathing.

01:11:03.880 | However, in that time, you're also going to want to find

01:11:07.040 | some sort of time measuring device,

01:11:09.100 | like it could be your phone or it could be a stopwatch.

01:11:11.980 | What I'm going to ask you to do in a few minutes

01:11:14.280 | is I'm going to ask you to inhale through your nose

01:11:17.880 | as deeply as you possibly can.

01:11:19.880 | That is, you're going to fill your lungs

01:11:21.400 | as much as you can through your nose.

01:11:23.720 | And then start a timer and measure how long it takes

01:11:28.720 | for you to deliberately control that exhale

01:11:32.400 | until your lungs are empty.

01:11:33.920 | Okay, so this is going to be a controlled exhale

01:11:36.240 | through the nose after a big, deep breath.

01:11:38.800 | But for the time being, keep breathing

01:11:40.320 | at a kind of calm, regular cadence.

01:11:42.760 | Okay, so you can find that time measuring device now,

01:11:45.160 | or you can come back to it later if you like.

01:11:47.200 | When I say inhale, you're going to inhale

01:11:49.120 | as deeply as you can through your nose,

01:11:51.240 | remembering that the diaphragm can really help you here

01:11:53.780 | to get a deep inhale by having your belly

01:11:56.880 | move out while you inhale.

01:11:58.980 | And then when I say start,

01:12:00.920 | you're going to measure the time that it takes

01:12:03.080 | to do a complete lungs empty exhale.

01:12:05.680 | In fact, I'll measure it for you.

01:12:08.040 | This will be one of the rare instances in this podcast

01:12:10.980 | where there's going to be a long period of silence

01:12:14.120 | as I measure something.

01:12:15.120 | So I've got a stopwatch here.

01:12:16.240 | So please prepare to do the big inhale

01:12:20.080 | and start inhaling now.

01:12:23.080 | So inhale as deeply as you can through your nose,

01:12:25.560 | fill your lungs as much as you can.

01:12:27.480 | Okay, now start, meaning slowly control the exhale

01:12:34.400 | through your nose.

01:12:35.480 | You're trying to let that air out as slowly as possible.

01:12:37.560 | And I'm just going to call out every 10 or 15 seconds or so.

01:12:42.040 | And you want to note when your lungs are empty.

01:12:44.920 | I know you can hold your breath with your lungs empty.

01:12:47.120 | That is not an accurate measure, 15 seconds.

01:12:49.880 | It is important that you know when your lungs are empty

01:12:55.400 | and that you're trying to control the exhale

01:12:57.300 | as much as possible so that you don't arrive

01:12:59.480 | at that lungs empty time too quickly.

01:13:02.960 | I'll explain what too quickly means, 30 seconds.

01:13:06.360 | Okay, for those of you that have already

01:13:10.160 | reached lungs empty, please go back to breathing normally.

01:13:14.420 | For those of you that haven't,

01:13:16.460 | can hang in here a little longer.

01:13:18.600 | If you're still discarding that air, 45 seconds.

01:13:21.620 | And we're rounding toward a minute, not quite there.

01:13:25.800 | Some of you are probably still letting out that air.

01:13:28.600 | I want to point out none of this has to do

01:13:30.520 | with cardiovascular fitness level,

01:13:32.320 | at least not in any kind of direct way.

01:13:34.260 | And 60 seconds.

01:13:36.620 | And I realized there will be a small subset of you out there

01:13:39.180 | that are still expelling your air in a slow lungs,

01:13:43.420 | slow exhale manner through the nose.

01:13:45.800 | Okay, so what we just did is a back of the envelope

01:13:48.180 | carbon dioxide discard rate, okay?

01:13:51.480 | If you need to pause this and go back and try it again,

01:13:54.360 | you just want to time how long it takes you

01:13:55.880 | to go from lungs full to lungs empty.

01:13:58.000 | Again, with the full understanding,

01:13:59.560 | I know that you can all sit there like beasts

01:14:01.400 | and hold your breath with your lungs empty,

01:14:03.160 | but please don't do that,

01:14:04.120 | because that's not going to be informative

01:14:06.000 | for what I'm telling you now.

01:14:07.520 | What I'm going to tell you now

01:14:08.360 | is that if it took you 20 seconds or less

01:14:12.400 | to expel all your air,

01:14:14.520 | that is you couldn't extend that exhale

01:14:16.400 | longer than 20 seconds,

01:14:17.840 | in a kind of back of the envelope way,

01:14:20.640 | we can say that you have a relatively brief

01:14:23.400 | or low carbon dioxide tolerance, okay?

01:14:27.040 | If it took you somewhere between 25 and 40,

01:14:31.160 | maybe 45 seconds to expel all your air,

01:14:34.120 | that is you could control that exhale

01:14:36.000 | for about 45 seconds or 30 seconds,

01:14:39.040 | then you have a moderate level of carbon dioxide tolerance.

01:14:43.640 | And if, for instance, you were able to go 50 seconds

01:14:46.680 | or longer for that discard until you hit lungs empty,

01:14:50.080 | you have a fairly high degree of carbon dioxide tolerance.

01:14:53.040 | Now, here's the deal.

01:14:55.120 | If you had low carbon dioxide tolerance,

01:14:57.840 | that is your 20 seconds or less,

01:14:59.520 | you're going to write down the number three, okay?

01:15:03.000 | If you had moderate levels of carbon dioxide tolerance,

01:15:05.840 | you're going to write down the number five,

01:15:08.860 | or you could even put five to six.

01:15:11.340 | And then if you are in that bracket of people

01:15:14.440 | that was able to discard your air

01:15:16.620 | over a period of 50 seconds or more,

01:15:18.880 | you're going to write down the number eight to 10, okay?

01:15:23.480 | Now, what are these numbers?

01:15:24.600 | What are we talking about?

01:15:25.480 | And before we get into what to do with these numbers,

01:15:28.440 | I want to emphasize again,

01:15:29.980 | this does not have to do with fitness level per se.

01:15:32.840 | I know some world-class triathletes

01:15:35.280 | that have very fast carbon dioxide blow off times,

01:15:38.400 | that is their discard rates are 20 seconds or less.

01:15:40.800 | I should also point out that if you're very stressed,

01:15:42.940 | that number is going to be very small.

01:15:44.800 | If you're very relaxed,

01:15:45.860 | like you just woke up after a long night of sleep

01:15:48.300 | and you feel great, that number is going to be extended, okay?

01:15:50.700 | So this is a back of the envelope measure

01:15:52.600 | that you're going to use each time

01:15:54.560 | you decide to do the exercise

01:15:55.980 | I'm going to tell you about in a moment.

01:15:57.340 | And the exercise I'm going to tell you about in a moment

01:15:59.580 | can be done every day if you like,

01:16:01.700 | but what the most interesting studies, at least to me,

01:16:05.060 | indicate is that you could do the exercise

01:16:07.140 | I'll tell you about even just once or twice a week

01:16:09.640 | and greatly improve your efficiency of breathing

01:16:13.260 | and shift yourself away from over-breathing when at rest,

01:16:16.040 | even if you're not thinking

01:16:17.020 | about how you're breathing at rest.

01:16:18.660 | Okay, so what is this exercise?

01:16:20.140 | Well, you just got your number,

01:16:21.740 | either low, medium or high bracket number

01:16:24.260 | for carbon dioxide discard rate.

01:16:26.980 | Remember if you're in the low category, your number is three.

01:16:29.540 | If you're medium, it's five to six.

01:16:31.280 | And if you are in the long carbon dioxide discard rate,

01:16:34.700 | long duration carbon dioxide discard rate,

01:16:36.280 | that is eight to 10 is your number.

01:16:38.580 | Now you're going to do two minutes

01:16:41.100 | of what most people would call box breathing.

01:16:43.420 | What is box breathing?

01:16:44.440 | Box breathing are equal duration,

01:16:47.260 | inhale, hold, exhale, hold, repeat.

01:16:51.200 | So inhale, hold, exhale, hold.

01:16:53.180 | Sounds very easy, right?

01:16:54.540 | How long do you inhale and then hold, exhale and then hold?

01:16:59.540 | Well, you now know if you were in the low group

01:17:03.020 | of carbon dioxide discard rate,

01:17:04.420 | your inhale is going to be three seconds,

01:17:05.820 | your hold will be three seconds,

01:17:07.420 | your exhale will be three seconds,

01:17:09.240 | and then you repeat, three seconds.

01:17:11.020 | So each sides of the box, if you will,

01:17:13.040 | is going to be three seconds long.

01:17:14.220 | If you were in the moderate carbon dioxide

01:17:16.760 | discard rate category, then you're going to inhale

01:17:20.020 | for five to six seconds, hold for five to six,

01:17:22.580 | exhale for five to six, hold for five to six,

01:17:24.880 | repeat for about two minutes.

01:17:26.280 | You could do three minutes if you want,

01:17:27.900 | but I think it's important to have protocols

01:17:30.240 | that are feasible for most people.

01:17:31.960 | And that's going to mean doing things

01:17:33.520 | for about two to five minutes when it comes

01:17:36.120 | to these breath rehabilitation exercises

01:17:38.580 | for restoring normal breathing.

01:17:40.280 | And then of course, if you were in the long category

01:17:43.420 | of carbon dioxide discard rate,

01:17:45.520 | you should be able to do an eight to 10 second inhale,

01:17:48.760 | eight to 10 second hold, eight to 10 second exhale,

01:17:52.160 | eight to 10 second hold and repeat, okay?

01:17:55.020 | So you could do that exercise now if you like,

01:17:57.840 | or you could do it at some point offline.

01:18:00.280 | You can pause this podcast if you want and go try it.

01:18:02.820 | That's an exercise that you can do

01:18:05.720 | for about two to three minutes, once or twice per week.

01:18:09.600 | What's happening when you do that exercise?

01:18:11.480 | Well, first of all, you are greatly increasing

01:18:14.880 | your neural mechanical control over the diaphragm.

01:18:18.200 | This is very important.

01:18:19.240 | Most people are not aware of this phrenic nerve pathway

01:18:21.720 | in the diaphragm and you're greatly increasing

01:18:24.740 | your mechanical control over this pathway

01:18:26.720 | through the process we call neuroplasticity.

01:18:29.080 | When you deliberately focus on a aspect

01:18:32.360 | of your nervous system control,

01:18:33.620 | in particular nervous system control over musculature

01:18:36.100 | that normally is subconscious

01:18:37.620 | and you're not paying attention to,

01:18:38.700 | and when you actively take control of that,

01:18:41.000 | it requires that your brain adjust and rewire

01:18:45.240 | the relationship between the different components

01:18:47.000 | of that circuit.

01:18:47.840 | And the wonderful thing is that has been shown

01:18:50.400 | to lead to changes in your resting pattern of breathing.

01:18:53.800 | Now, why did we go through the whole business

01:18:56.000 | of doing the carbon dioxide tolerance test?

01:18:58.020 | Well, for people who don't tolerate carbon dioxide very well,

01:19:00.640 | they don't have very good phrenic,

01:19:03.180 | that is neuro-mechanical control of the diaphragm

01:19:06.000 | for whatever reason.

01:19:06.840 | Again, it doesn't mean you're not fit.

01:19:08.480 | It just means you don't have or you have not yet developed

01:19:11.580 | neuro-mechanical control of the diaphragm.

01:19:13.640 | It would be near impossible for you to do box breathing

01:19:16.840 | for two or three minutes with eight seconds in,

01:19:19.040 | eight seconds hold, eight seconds exhale, eight second hold.

01:19:21.760 | So that's why we do a test

01:19:24.480 | to see what you're capable of doing.

01:19:26.440 | You don't want the box breathing to be too strained

01:19:29.160 | where you're really challenged to get around the whole box.

01:19:33.160 | You want it to be relatively easy

01:19:34.560 | because remember you're trying to translate this pattern

01:19:36.780 | to your normal pattern of breathing.

01:19:39.160 | That is your pattern of breathing

01:19:40.360 | when you're not consciously thinking about breathing.

01:19:42.560 | And what are we really translating

01:19:44.620 | when we do this box breathing type exercise?

01:19:46.680 | What you're translating is the ability

01:19:49.440 | to pause between breaths

01:19:51.240 | and yet take full mechanically driven breaths

01:19:56.240 | that involve the phrenic nerve and diaphragm.

01:19:58.040 | So again, you're encouraging,

01:19:59.840 | especially if you use nasal breathing

01:20:01.280 | when you do the box breathing,

01:20:02.700 | you're encouraging phrenic control over the diaphragm

01:20:06.040 | and you're getting that six liters of air per minute or so

01:20:09.960 | using fewer and fewer breaths over time.

01:20:12.640 | So this is a, again, zero cost,

01:20:14.640 | although it does cost a little bit of time,

01:20:15.960 | zero cost approach to adjusting

01:20:18.200 | your normal pattern of breathing at rest,

01:20:20.300 | which has a huge number of positive outcomes

01:20:23.600 | in terms of your ability to stay relatively calm,

01:20:27.040 | to not get the hyperexcitability of the brain.

01:20:29.680 | It has actually been shown in various studies,

01:20:32.240 | and we'll talk about one in particular later,

01:20:34.220 | to greatly improve not just levels of calm

01:20:38.240 | and reduce bouts of stress,

01:20:39.900 | but also improve nighttime sleep.

01:20:41.740 | There are a huge number of benefits

01:20:43.040 | that can come from doing this box breathing exercise,

01:20:45.120 | but you got to get the duration of the sides of the box right

01:20:47.480 | and that's why you do the carbon dioxide tolerance test.

01:20:50.280 | One thing that many people notice

01:20:51.680 | after doing the carbon dioxide tolerance test,

01:20:53.680 | even just once,

01:20:54.680 | and then doing this box breathing exercise

01:20:57.820 | once or twice a week,

01:20:59.240 | is that after two or three weeks,

01:21:01.640 | the box breathing itself becomes very easy.

01:21:04.440 | And in that case,

01:21:05.360 | I recommend taking the carbon dioxide tolerance test

01:21:07.760 | over again,

01:21:08.680 | and almost always what you'll find

01:21:10.940 | is that you have been able to extend

01:21:13.380 | your carbon dioxide discard rate,

01:21:15.400 | and therefore you now fall into a different category,

01:21:19.520 | not just the lower medium,

01:21:21.360 | but the long carbon dioxide discard rate category,

01:21:24.960 | and you are able to extend the duration

01:21:27.600 | of those inhale hold exhale holds during the box breathing.

01:21:31.080 | And of course,

01:21:31.920 | the ultimate benefit of all this is that it translates

01:21:35.680 | to deeper and yet less frequent breathing when at rest

01:21:40.480 | and when not consciously paying attention

01:21:42.440 | to how you're breathing during the daytime.

01:21:44.280 | Again, if at all possible,

01:21:45.580 | do all of this breathing through the nose.

01:21:48.200 | For those of you that have a severely occluded nose,

01:21:51.080 | the recommendation always is to breathe

01:21:53.560 | through your nose more,

01:21:54.640 | but I do realize that for some people,

01:21:55.840 | it's really uncomfortable to breathe through the nose

01:21:57.720 | because they have such an occluded nasal pathway.

01:22:00.060 | And for you folks,

01:22:01.760 | doing some of this breathing through the mouth

01:22:03.400 | can probably suffice,

01:22:05.560 | but if at all possible,

01:22:06.960 | do the breathing through the nose.

01:22:08.560 | And please also let me know how your progress

01:22:11.840 | evolves over time with the carbon dioxide discard rate

01:22:14.240 | and the box breathing.

01:22:15.520 | And of course the positive shifts that occur

01:22:17.640 | in normal unconscious daytime breathing

01:22:20.300 | translate to all the opposite things that we talked about

01:22:23.920 | when you are over-breathing during the daytime.

01:22:26.920 | So what I just described

01:22:28.040 | in terms of the carbon dioxide tolerance test

01:22:30.480 | and the exercise using box breathing

01:22:33.360 | to restore normal patterns of breathing and not over-breathe

01:22:37.300 | and therefore not eliminate too much carbon dioxide

01:22:40.000 | is exactly the two tests that were incorporated into a study

01:22:43.960 | that my laboratory did in collaboration

01:22:45.880 | with our associate chair of psychiatry

01:22:48.000 | at Stanford School of Medicine, Dr. David Spiegel,

01:22:50.120 | who's also been a guest on this podcast previously.

01:22:52.940 | And that study explored box breathing,

01:22:56.420 | but it also explored other forms of breathing

01:22:58.700 | and actually compare those forms of deliberate breathing

01:23:01.240 | to meditation as a means to explore

01:23:04.840 | what are going to be the minimal effective doses

01:23:08.580 | and most effective ways to chronically reduce stress

01:23:12.780 | around the clock and improve mood and improve sleep.

01:23:16.800 | So the study I'm referring to was just published recently.

01:23:19.960 | It's entitled Brief Structured Respiration Practices,

01:23:23.120 | Enhance Mood and Reduce Physiological Arousal.

01:23:25.960 | We will also provide a link to this paper

01:23:27.560 | in the show note captions.

01:23:29.140 | What this study really focused on was a simple question,

01:23:32.400 | which is what is the shortest and most effective practice

01:23:36.420 | that people can use

01:23:37.840 | in order to reduce their levels of stress,

01:23:40.720 | not just during that breath work practice

01:23:43.240 | or meditation practice, but around the clock,

01:23:45.600 | 24 hours a day, including improvements in sleep.

01:23:48.880 | And we were excited to do this study

01:23:50.440 | because many studies had explored how meditation,

01:23:53.540 | or in some cases, fewer studies,

01:23:56.280 | had explored how breath work can impact

01:23:58.560 | different brain states or bodily states.

01:24:00.520 | But very few studies had explored

01:24:03.000 | how those breath work or meditation practices

01:24:05.720 | influenced body brain states around the clock

01:24:08.820 | when people were not performing the particular meditation

01:24:11.840 | or breath work practice.

01:24:13.400 | The reason we were able to do this study

01:24:15.320 | was really fortunate.

01:24:16.820 | The folks over at WHOOP were generous enough

01:24:18.480 | to donate a bunch of WHOOP straps,

01:24:20.260 | which allowed us to measure heart rate variability,

01:24:23.740 | a number of other different physiological parameters.

01:24:26.180 | We also got subjective reports

01:24:27.960 | about people's mood and feelings of wellbeing.

01:24:29.820 | We got data about their sleep

01:24:31.800 | pinged to us from remote locations.

01:24:34.760 | So these people,

01:24:35.580 | rather than being brought to the laboratory

01:24:37.140 | and being in a very artificial circumstance, the laboratory,

01:24:41.120 | as much as we like to think our laboratory is realistic,

01:24:43.720 | we have virtual reality and things like that,

01:24:45.240 | there's nothing as realistic as the real world.

01:24:47.200 | And so we were able to have more than a hundred subjects

01:24:49.440 | out in the real world, living their real lives,

01:24:51.940 | pinging back to us data all the time, 24 hours a day,

01:24:55.360 | so that we could measure

01:24:56.720 | how their different interventions that we asked them to do,

01:25:00.080 | breath work practices or meditation practices,

01:25:01.940 | were impacting physiological parameters.

01:25:04.160 | And they were also informing us regularly

01:25:06.200 | about their subjective mood, et cetera.

01:25:08.200 | We got a lot of data, as you can imagine.

01:25:11.480 | And the basic takeaway from the study was twofold.

01:25:13.880 | First of all, we discovered that deliberate breath work

01:25:17.960 | practices done for about five minutes per day

01:25:21.960 | across the course of about a month,

01:25:23.780 | led to greater reductions in stress

01:25:28.200 | than did a five minute a day meditation practice.

01:25:31.280 | Now, that is not to say that meditation is not useful.

01:25:33.880 | In fact, there are dozens, if not hundreds of papers,

01:25:37.320 | including one particular, I should say,

01:25:39.980 | particularly beautiful study from Wendy Suzuki's lab

01:25:42.680 | at New York University showing that a daily 10 to 13 minute

01:25:47.080 | mindfulness meditation practice can greatly improve focus,

01:25:51.260 | memory, and a number of other things

01:25:52.780 | related to cognition and learning.

01:25:54.720 | However, the research on meditation has shown us

01:25:57.480 | that meditation, at least short meditations,

01:25:59.860 | mainly lead to improvements in focus and memory,

01:26:03.680 | not so much reductions in stress,

01:26:05.440 | although they do lead to reductions in stress.

01:26:08.020 | What we found was that any number

01:26:10.720 | of different breath work practices,

01:26:12.000 | and we explored three, done for five minutes a day,

01:26:15.240 | outperformed meditation in terms of the ability

01:26:18.400 | of breath work to reduce stress around the clock

01:26:22.160 | compared to meditation.

01:26:23.840 | The three types of breath work that we explored

01:26:26.080 | also showed different effects.

01:26:28.400 | I should mention the three types of breath work

01:26:30.040 | that we compared were box breathing

01:26:32.840 | of the sort that you just learned about.

01:26:34.860 | We compared that to something called cyclic sighing,

01:26:38.680 | which involves two inhales through the nose

01:26:42.300 | to get maximally inflated lungs, followed by a long exhale.

01:26:45.640 | I'll return to that in a moment.

01:26:47.440 | That was repeated for five minutes at a time

01:26:49.360 | for each session.

01:26:50.600 | And a third breath work practice,

01:26:52.180 | which was cyclic hyperventilation,

01:26:53.780 | which as the name suggests,

01:26:55.200 | involves people inhaling deeply through the nose,

01:26:58.500 | then exhaling passively through the mouth,

01:27:00.380 | and then repeating inhale through the nose,

01:27:02.060 | exhale through the mouth, repeating that for 25 cycles,

01:27:04.840 | one cycle being an inhale and an exhale.

01:27:07.240 | So that equals one cycle.

01:27:08.280 | Repeating that for 25 cycles,

01:27:09.880 | then exhaling all their air and holding their breath

01:27:12.220 | with lungs empty for about 15 to 30 seconds,

01:27:14.360 | and then repeating inhale, exhale,

01:27:16.720 | cyclic hyperventilation for the duration of five minutes.

01:27:20.080 | Okay, so people were divided into these different groups,

01:27:22.000 | either mindfulness meditation, where they sat,

01:27:24.200 | they were not told to control their breathing

01:27:25.720 | in any specific way.

01:27:26.600 | They closed their eyes, they focused their attention

01:27:29.160 | on a region just behind their forehead.

01:27:31.440 | One group did that.

01:27:32.280 | The other group did cyclic sighing.

01:27:34.460 | Another group did box breathing.

01:27:37.280 | Another group did cyclic hyperventilation.

01:27:40.720 | As any sort of clinical trial like this ought to,

01:27:43.720 | we then swapped people into different groups

01:27:45.840 | so they served as their own control,

01:27:47.560 | so we could evaluate any kind of between

01:27:49.780 | and within individual variability.

01:27:52.720 | Again, there are a lot of data in this paper,

01:27:55.300 | but the takeaway was that for the sake of stress reduction

01:27:59.720 | around the clock, and for the sake of improving sleep

01:28:03.200 | and mood, the most effective practice of the four practices

01:28:06.720 | that we examined was the cyclic sighing.

01:28:08.760 | Again, cyclic sighing is performed the following way.

01:28:11.280 | You inhale through the nose as deeply as you can,

01:28:13.200 | then you do a second inhale immediately afterwards

01:28:16.060 | to try and maximally inflate the lungs.

01:28:18.440 | In fact, that's what happens.

01:28:19.680 | We know that during that second inhale,

01:28:22.200 | even if it's just a very sharp, short inhale,

01:28:25.720 | the extra physical vigor that's required

01:28:28.800 | to generate that second inhale

01:28:30.560 | causes those aviolae of the lungs,

01:28:33.760 | which may have collapsed, and indeed in between breaths,

01:28:37.860 | and often even just through the course of the day,

01:28:39.980 | and especially if we get stressed,

01:28:41.880 | those aviolae of the lungs start to collapse,

01:28:44.520 | and because they're damp on the inside,

01:28:46.760 | they have a little bit of fluid,

01:28:48.060 | they're like a balloon with a little bit of fluid

01:28:49.880 | in the middle, it takes a little bit of physical force

01:28:52.200 | to pop those open.

01:28:54.280 | Now, you're not literally exploding them pop,

01:28:55.860 | but you're reinflating them with air,

01:28:58.500 | and then you perform the long exhale through the mouth

01:29:03.000 | until lungs are empty, so it looks exactly like this.

01:29:05.880 | Now, we know that one single physiological sigh

01:29:17.800 | of the sort that I just described

01:29:20.080 | performed at any time of day under any conditions,

01:29:23.780 | whether or not you're about to walk on stage to give a talk,

01:29:25.760 | or you're in a meeting and you're feeling stressed,

01:29:28.080 | or you're in a conversation that's very stressful,

01:29:30.520 | or you can feel stress mounting because you're in traffic,

01:29:32.720 | or any number of psychological or physical stressors

01:29:35.920 | that may be approaching you or you feel are oppressing you,

01:29:39.880 | doing one physiological sigh

01:29:41.880 | of the sort that I just described

01:29:43.920 | is the fastest physiologically verified way

01:29:48.080 | that we are aware of to reduce your levels of stress

01:29:52.440 | and to reintroduce calm,

01:29:54.240 | that is to shift your autonomic nervous system

01:29:56.700 | from a state of heightened levels of autonomic arousal

01:30:00.200 | that is sympathetic nervous system, as it's called,

01:30:02.400 | is at a higher activation level

01:30:04.320 | than the so-called parasympathetic nervous system.

01:30:06.400 | Again, sympathetic nervous system,

01:30:07.720 | having nothing to do with sympathy,

01:30:08.800 | has everything to do with so-called fight or flight,

01:30:11.500 | although it controls other things too,

01:30:12.680 | including positive arousal.

01:30:14.120 | And the parasympathetic nervous system,

01:30:15.940 | often referred to as the rest and digest system,

01:30:17.840 | although it does other things too,

01:30:20.380 | is associated with calming.

01:30:21.440 | Those two things are always in kind of push-pull

01:30:23.240 | with one another, like a seesaw or push-pull,

01:30:25.480 | however you want to think about it.

01:30:26.840 | One physiological sigh, meaning that big, deep inhale,

01:30:30.040 | short second inhale, also through the nose,

01:30:31.940 | and then long exhale to completely lungs empty,

01:30:35.140 | is known to restore the level of balance

01:30:37.680 | in the sympathetic, parasympathetic neural circuitries,

01:30:41.900 | and is the fastest way to reintroduce calm.

01:30:44.960 | That's one physiological sigh.

01:30:47.640 | In this study, what we asked

01:30:48.960 | was that people perform that repeatedly,

01:30:51.180 | so-called cyclic sighing, for the duration of five minutes.

01:30:54.320 | And the people who did that cyclic sighing

01:30:56.560 | for five minutes a day,

01:30:58.080 | regardless of the time of day that they did it,

01:31:00.280 | experienced the greatest reductions in stress,

01:31:02.840 | not just during the practice, but around the 24-hour cycle,

01:31:06.740 | and it translated, again,

01:31:07.980 | to all sorts of positive subjective changes,

01:31:09.820 | improvements in sleep.

01:31:11.720 | Lower resting heart rate at all times of day,

01:31:14.560 | so this is important.

01:31:15.400 | Again, this study was not just exploring

01:31:18.000 | what happens during meditation or breath work,

01:31:20.180 | cyclic sighing, et cetera,

01:31:21.760 | it was exploring how the changes that occur

01:31:24.200 | during that practice translate to changes in breathing

01:31:27.680 | and heart rate, mood, et cetera, throughout the 24-hour cycle

01:31:30.500 | so the takeaway here is twofold.

01:31:32.160 | First of all, if you're somebody

01:31:33.560 | who wants to improve your mood

01:31:35.360 | and reduce your overall levels of stress,

01:31:38.360 | and you only have five minutes a day to invest in that,

01:31:41.880 | hopefully you're doing all the other things

01:31:43.160 | like trying to get proper sleep and exercise,

01:31:45.080 | social connection, nutrition, et cetera,

01:31:46.680 | sunlight in the morning, of course, can't leave that out,

01:31:50.120 | but if you were going to devote five minutes a day

01:31:52.760 | to a stress reduction practice that is now supported by data

01:31:56.280 | to translate to reductions in stress around the clock,

01:31:59.820 | the data say that you would want to invest that

01:32:03.080 | in cyclic sighing, that is double inhale through the nose,

01:32:06.440 | extended exhale through the mouth

01:32:07.920 | until your lungs are empty,

01:32:08.820 | then repeat for five minutes a day.

01:32:10.660 | You, of course, if you like, could do meditation.

01:32:13.400 | It still had positive effects, meaning it reduced stress,

01:32:15.760 | although not as much as cyclic sighing.

01:32:17.480 | You could do box breathing if you want

01:32:19.860 | for the purpose of reducing stress.

01:32:21.660 | All the practices we explored did reduce stress,

01:32:24.560 | but cyclic sighing performed for five minutes a day

01:32:26.860 | had the most robust and pervasive effect

01:32:29.360 | in reducing stress, improving mood, and improving sleep.

01:32:32.240 | That's the first message of the study.

01:32:33.640 | The second takeaway is that one physiological sigh,

01:32:37.800 | that's right, just one physiological sigh,

01:32:40.240 | where you inhale deeply through the nose,

01:32:41.720 | another inhale through the nose

01:32:42.820 | to maximally inflate the oviolae of the lungs,

01:32:44.880 | and then you exhale to completely lungs empty

01:32:49.040 | and then go back to normal breathing,

01:32:50.880 | is the fastest way to introduce a level of calm

01:32:54.640 | and to reduce your overall levels of stress in real time.

01:32:57.800 | And this is very important.

01:32:58.880 | I think that out there these days,

01:33:00.640 | we hear a lot about stress reduction techniques,

01:33:02.520 | and most all of the stress reduction techniques

01:33:05.360 | that have been explored,

01:33:06.320 | everything from massage to meditation to breath work

01:33:09.420 | to a hot shower to a foot rub will calm you down.

01:33:13.080 | The question is, do they calm you down

01:33:14.640 | just during that practice?

01:33:16.560 | Great if it does,

01:33:18.400 | but does it also translate to reduce levels of stress

01:33:21.620 | at other times in the 24 hour cycle

01:33:23.540 | and other positive effects as well?

01:33:25.220 | So one physiological sigh is a very efficient way

01:33:28.280 | to adjust that ratio of sympathetic

01:33:31.800 | to parasympathetic activation

01:33:33.220 | and immediately bring about calm.

01:33:34.640 | So it's excellent for real time control of stress.

01:33:37.420 | The other thing about physiological sighs

01:33:38.880 | is that it's not a hack.

01:33:39.920 | It's not the application of a breathing practice

01:33:42.320 | to something that it wasn't intended for.

01:33:44.080 | In fact, physiological sighs

01:33:45.680 | were not discovered by me at all.

01:33:48.200 | They were discovered by physiologists in the 1930s

01:33:51.360 | who found that when people underbreathe,

01:33:53.720 | they have a buildup of carbon dioxide in their system.

01:33:57.240 | And even though carbon dioxide is essential for life,

01:33:59.840 | you don't want too much of it in your system.

01:34:01.560 | And that people, whether or not they were asleep or awake,

01:34:05.280 | would engage a physiological sigh

01:34:07.640 | spontaneously, subconsciously.

01:34:09.720 | They would do this double inhale through the nose

01:34:11.400 | and extended exhale through the mouth.

01:34:13.600 | And that did not just eliminate excessive carbon dioxide

01:34:17.200 | from the system.

01:34:18.100 | It also rebalanced the oxygen carbon dioxide ratio

01:34:21.380 | in the proper ways.

01:34:22.280 | In fact, it's observed in animals.

01:34:23.920 | You might see this in animals that are tired.

01:34:26.120 | When animals or humans get tired,

01:34:27.760 | they tend to start underbreathing a little bit.

01:34:30.100 | And that can often disrupt the balance

01:34:32.040 | of carbon dioxide and oxygen.

01:34:33.320 | And right before a dog will go down for a nap, for instance,

01:34:35.540 | you'll notice that it'll do this double inhale exhale.

01:34:38.220 | People, when they are sleeping,

01:34:39.640 | if they hold their breath for a period of time,

01:34:41.740 | which frankly all of us do periodically throughout sleep,

01:34:44.800 | they will engage a spontaneous physiological sigh.

01:34:49.140 | During the daytime, we are often holding our breath,

01:34:51.380 | especially nowadays.

01:34:52.240 | And there's a study on this

01:34:53.860 | that we'll talk about a little bit later

01:34:55.220 | where when people text message or they're emailing,

01:34:57.280 | although nowadays people are mainly on social media

01:34:59.340 | and text messaging, they often are holding their breath.

01:35:01.380 | They will follow a breath hold by a physiological sigh

01:35:04.420 | because during that breath hold,

01:35:05.760 | they're building up the level of carbon dioxide

01:35:07.580 | in their system.

01:35:08.420 | Now, mind you, I spent close to a half an hour telling you

01:35:10.740 | that most people are over-breathing at rest.

01:35:13.100 | And that's also true.

01:35:14.680 | But people often will shift from over-breathing

01:35:17.500 | to under-breathing, which is a terrible pattern.

01:35:20.740 | So physiological sigh is done either as a one-off,

01:35:24.660 | one physiological sigh to clamp stress

01:35:26.980 | or reduce stress in real time,

01:35:28.340 | or repeatedly over five minutes as a practice

01:35:30.880 | that you do each day is going to be

01:35:33.380 | not just the most effective way to approach

01:35:35.460 | reducing stress around the clock and in real time,

01:35:38.720 | but also the one that's highly compatible

01:35:41.420 | with the way that the neural circuits

01:35:42.620 | that control breathing were designed.

01:35:44.360 | The physiological sigh has some other

01:35:45.940 | very useful applications.

01:35:48.060 | One of the more, I would say useful ones,

01:35:50.740 | at least to those of you that exercise

01:35:52.900 | is going to be the use of physiological sigh

01:35:55.500 | in order to remove the so-called side stitch.

01:35:57.900 | So if you've ever been running or swimming or exercising,

01:36:01.140 | you felt a cramp on your right side,

01:36:03.660 | chances are, despite what your high school PE coach told you

01:36:07.020 | that raising your arms above your head

01:36:08.980 | or drinking less water before you exercise

01:36:11.340 | is not going to get rid of that cramp.

01:36:13.880 | And here's why, it's not a cramp at all.

01:36:17.220 | If you recall the cervical three, four, and five nerves

01:36:21.660 | that give rise to the phrenic nerve

01:36:23.660 | and go down and innervate your diaphragm,

01:36:26.380 | well, as I mentioned before,

01:36:28.180 | a certain number of those nerve fibers

01:36:29.820 | actually course into the diaphragm and go up underneath.

01:36:32.940 | And if you recall earlier,

01:36:34.420 | I also said that the diaphragm sits right

01:36:36.380 | on top of the liver.

01:36:37.940 | In other words, you actually have a sensory innervation

01:36:41.020 | of the diaphragm, the deep diaphragm,

01:36:43.460 | and the liver.

01:36:44.680 | And there's something called a referenced pain,

01:36:47.260 | which is what people generally experience

01:36:49.960 | when they have that side stitch on their right-hand side.

01:36:52.540 | So if you're ever exercising and you feel a cramp

01:36:55.060 | on your right-hand side,

01:36:57.100 | it's possible that it's a genuine cramp,

01:36:59.420 | but more likely is the fact

01:37:01.900 | that that phrenic nerve sensory innervation

01:37:04.480 | is now being carried up to your brain

01:37:07.160 | and you are detecting some local or referenced pain

01:37:11.320 | in the liver and in the diaphragm.

01:37:14.340 | Now that doesn't necessarily mean

01:37:15.580 | you're doing anything wrong,

01:37:16.660 | although you might not be breathing properly

01:37:19.320 | for running at that moment.

01:37:20.700 | And that's what gave rise to it.

01:37:21.720 | It could be some spasming of the phrenic nerve

01:37:24.380 | or some inefficient breathing during running.

01:37:26.420 | We had an entire series on fitness with Dr. Andy Galpin.

01:37:29.420 | One of those episodes included

01:37:31.040 | a lot of information on breathing.

01:37:32.400 | It was the episode on endurance,

01:37:34.900 | although breathing was a topic that was thread

01:37:37.200 | through multiple episodes in that series.

01:37:38.920 | You can find that series at hubermanlab.com.

01:37:40.940 | Talks a lot about how to breathe during running,

01:37:42.780 | how to breathe during weightlifting, et cetera.

01:37:44.780 | But the point for now is that

01:37:46.820 | if ever you're experiencing that right side side stitch,

01:37:50.300 | I encourage you to perform the physiological sigh.

01:37:53.940 | And the good news is you can perform it

01:37:55.420 | while still running or while still swimming.

01:37:57.940 | Although I suppose with swimming,

01:37:58.920 | you might have to make some adjustments

01:38:01.220 | because of course you don't want to inhale water

01:38:03.660 | or while cycling or any type of activity.

01:38:08.500 | If you perform that physiological sigh

01:38:10.900 | generally two or three times,

01:38:12.900 | what will occur is that

01:38:14.060 | because of changes in the firing of the phrenic nerve

01:38:16.300 | and in particular because of changes in the sensory feedback

01:38:19.540 | from the sensory component of the phrenic nerve

01:38:21.580 | back to the brain,

01:38:23.020 | you will experience an alleviation of the pain

01:38:26.220 | from that right side side stitch.

01:38:28.460 | In other words, you can get rid of side cramps

01:38:30.180 | during physiological sighs during activities,

01:38:32.500 | in particular during running activities.

01:38:34.900 | Now, I should also mention that

01:38:36.140 | if you're experiencing a side stitch on the left side,

01:38:39.880 | chances are that has to do with excessive air

01:38:43.700 | or fluid in your stomach.

01:38:46.020 | And there are reasons for that

01:38:47.300 | that also have to do with the way that the phrenic nerve

01:38:49.420 | is it's bilateral and branches to both sides

01:38:51.920 | and is catching sensory input on the left side

01:38:54.760 | from some of the local organs

01:38:56.460 | and sensory innervation of those organs.

01:38:58.460 | Okay, but if you have right side side stitch,

01:39:00.440 | the physiological side done two or three times

01:39:02.500 | while still running ought to relieve that side stitch.

01:39:04.980 | Now, as long as we're talking about breathing

01:39:06.740 | and the phrenic nerve and the relationship

01:39:08.360 | between the phrenic nerve and your liver and your stomach

01:39:12.140 | and some of the other organs in that neighborhood,

01:39:14.340 | we should talk about the relationship

01:39:15.500 | between breathing and heart rate.

01:39:17.900 | This is an incredibly important topic,

01:39:19.700 | so much so that I perhaps should have brought it up

01:39:21.800 | at the beginning of the episode.

01:39:23.380 | But nonetheless, you now know what your diaphragm does, right?

01:39:28.380 | When you inhale, your diaphragm moves down.

01:39:30.900 | That's right, when you can track your diaphragm,

01:39:32.820 | it moves down, it creates space for your lungs to inhale.

01:39:35.260 | And when you exhale, your diaphragm moves up.

01:39:37.700 | Well, when you inhale and your diaphragm moves down,

01:39:42.620 | what happens is there's more space created

01:39:45.060 | in the thoracic cavity.

01:39:46.620 | In particular, if you're also breathing deeply

01:39:48.380 | and you're using those intercostal muscles

01:39:49.980 | to expand your ribs.

01:39:51.720 | As a consequence, the heart actually gets

01:39:53.880 | a little bit bigger.

01:39:54.720 | It's a temporary enlargement in the heart,

01:39:57.100 | but it's a real enlargement.

01:39:58.660 | And as a consequence, whatever blood is in the heart

01:40:02.060 | is now in a larger volume 'cause the heart got bigger.

01:40:04.860 | And as a consequence, that blood is moving more slowly

01:40:07.540 | through that larger volume for a short period of time,

01:40:11.300 | but nonetheless, it's moving more slowly.

01:40:13.960 | Your nervous system detects that and sends a neural signal

01:40:17.460 | to the heart to speed the heart rate up.

01:40:19.420 | In other words, inhales increase heart rate.

01:40:22.740 | The opposite is true when you exhale.

01:40:26.240 | When you exhale, your diaphragm moves up,

01:40:29.540 | your rib cage tends to move inward a bit

01:40:32.140 | and you compact the heart.

01:40:33.380 | You reduce the volume of the heart overall.

01:40:35.580 | When you reduce the volume of the heart overall,

01:40:38.620 | blood flow through the heart accelerates

01:40:41.460 | because it's a smaller volume.

01:40:42.820 | So a given unit of blood is going to move more quickly

01:40:44.580 | through that small volume.

01:40:45.920 | Your nervous system detects that and sends a signal

01:40:49.340 | to slow the heart down.

01:40:51.520 | So just as inhales speed the heart up,

01:40:54.340 | exhales slow your heart rate down.

01:40:57.340 | Now, of course, even though you can double up on inhales

01:41:00.180 | or even triple up on inhales, sooner or later,

01:41:03.220 | if you inhale, you're going to have to exhale, all right?

01:41:05.940 | And the converse is also true, of course.

01:41:08.140 | So what does this mean

01:41:09.220 | in terms of controlling your heart rate?

01:41:10.700 | Well, let's say you are going in for a blood draw

01:41:14.500 | or you're going out on stage and you're stressed.

01:41:16.820 | Well, I would encourage you to do a physiological side,

01:41:18.940 | maybe two physiological sides to bring your level of calm up

01:41:22.020 | and your level of stress down.

01:41:23.820 | Nonetheless, if you have any reason

01:41:25.620 | why you want to quickly reduce your heart rate

01:41:27.700 | or accelerate your heart rate

01:41:29.620 | for sake of physical work output

01:41:33.020 | or to calm yourself down additionally,

01:41:35.500 | not just use the physiological side,

01:41:37.640 | well, then you can take advantage of this relationship

01:41:39.680 | between inhales and exhales controlling heart rate.

01:41:42.380 | If you want to increase your heart rate,

01:41:44.520 | you can simply inhale longer and more vigorously

01:41:48.080 | relative to your exhales.

01:41:49.220 | And if you want to decrease your heart rate,

01:41:52.260 | well, then you're going to make your exhales longer

01:41:54.340 | and or more vigorous than your inhales.

01:41:56.540 | In fact, this process,

01:41:58.080 | which is called respiratory sinus arrhythmia

01:42:00.820 | is the basis of what we call heart rate variability.

01:42:03.440 | Heart rate variability involves the vagus nerve,

01:42:05.420 | the 10th cranial nerve,

01:42:06.820 | which is a parasympathetic nerve

01:42:08.660 | that is associated with a calming aspect

01:42:10.860 | of the autonomic nervous system,

01:42:12.560 | slowing your heart rate down by extending your exhales.

01:42:15.820 | And it really forms the basis of most

01:42:17.940 | all breathing practices.

01:42:19.340 | If you look at any breathing practices,

01:42:21.180 | whether or not it's Wim Hof breathing,

01:42:22.500 | Tummo breathing, Kundalini breathing, Pranayama breathing,

01:42:25.660 | physiological sighing, cyclic sighing,

01:42:27.540 | and on and on and on.

01:42:28.780 | If you were to measure the ratio of inhales to exhales

01:42:32.460 | and the vigor of inhales to exhales,

01:42:34.300 | what you would find is that each one would create

01:42:37.620 | a net increase or a net decrease in heart rate

01:42:41.100 | that could be very accurately predicted

01:42:43.500 | by whether or not that breathing practice

01:42:45.780 | emphasized inhales, emphasized exhales,

01:42:49.680 | or had those two features inhale and exhale

01:42:53.400 | be of equal duration and intensity.

01:42:55.500 | In fact, if you wanted to equilibrate your heart rate,

01:42:58.020 | what you would do is you would do box breathing

01:43:00.000 | because inhale, hold, exhale, hold is by definition

01:43:03.140 | creating equal duration inhales and exhales

01:43:06.520 | of essentially equivalent vigor.

01:43:08.680 | When you do a physiological sigh,

01:43:10.160 | you're doing two big inhales,

01:43:11.320 | which is going to speed your heart rate up

01:43:12.520 | just a little bit, but then a long extended exhale.

01:43:14.960 | The exhale in the end is much longer

01:43:17.720 | than the two inhales, even when combined.

01:43:19.960 | And so you get a net decrease in heart rate,

01:43:21.880 | the calming effect, and then practices

01:43:24.640 | such as Tummo breathing or Wim Hof breathing

01:43:26.400 | or cyclic hyperventilation, deep inhales and exhales,

01:43:30.920 | or the inhales are more vigorous

01:43:32.560 | compared to the more passive exhales

01:43:35.120 | are going to lead to increases in heart rate, okay?

01:43:37.400 | So the relationship between breathing and heart rate

01:43:39.400 | is an absolutely lockstep one

01:43:42.400 | where your heart rate follows your breathing,

01:43:45.740 | your heart rate and your breathing

01:43:46.940 | are in an intimate discussion with one another,

01:43:49.020 | but where always and forever,

01:43:51.580 | your inhales increase your heart rate,

01:43:53.880 | your exhales decrease it.

01:43:55.640 | Now, this feature, which physicians call

01:43:58.000 | respiratory sinus arrhythmia,

01:43:59.940 | or we sometimes hear about more often nowadays

01:44:02.240 | as heart rate variability is something that people in sport

01:44:06.120 | have known about for a very long time.

01:44:08.020 | It's why, for instance, that marksman will exhale

01:44:11.680 | just prior to taking a shot.

01:44:13.000 | That's particularly true for people

01:44:14.280 | that compete in the biathlon

01:44:15.580 | where they cross-country ski, so their heart rate

01:44:17.280 | is up, up, up, up, up.

01:44:18.160 | Then they'll get to the point

01:44:19.500 | where they actually have to shoot at a target

01:44:20.920 | and they'll exhale and then they'll shoot at the target.

01:44:24.140 | This is also why, for instance,

01:44:25.720 | if you want to bring your heart rate down very quickly

01:44:28.000 | between rounds of martial arts,

01:44:29.680 | there are a number of different ways to do that,

01:44:31.420 | but an extended exhale of any kind,

01:44:33.480 | or frankly, any breathing practice that emphasizes exhales

01:44:36.580 | is going to bring your heart rate down.

01:44:39.100 | This has been incorporated in a number of different contexts,

01:44:41.160 | including sport, military.

01:44:43.120 | It's also now being incorporated in the clinical context

01:44:45.840 | for people who feel a panic attack coming on.

01:44:48.300 | I'm very gratified to learn that the physiological side

01:44:51.120 | is now being explored as a tool

01:44:52.900 | to prevent panic attacks and anxiety attacks.

01:44:56.300 | This is prior to the panic attack,

01:44:58.020 | people bringing their heart rate down again

01:44:59.420 | through those extended exhales.

01:45:01.080 | So learning to extend your exhale

01:45:03.420 | is really a terrific skill to master,

01:45:05.700 | and it's a very easy skill to master, frankly.

01:45:08.120 | Why do I say a skill?

01:45:09.280 | Well, remember what I said earlier,

01:45:10.880 | which is that humans inhale actively

01:45:14.360 | and most typically will passively exhale,

01:45:17.340 | just let the air drop out of them at whatever rate,

01:45:20.180 | depending on how much air they inhaled.

01:45:22.120 | Actively exhaling, that is actively relaxing the diaphragm

01:45:28.200 | and actively relaxing those intercostal muscles

01:45:30.980 | of the chest, those ones, or I should say between the ribs,

01:45:34.580 | is a skill that you can very quickly acquire

01:45:36.940 | and will allow you to use that relationship

01:45:39.480 | between the phrenic nerve, the diaphragm,

01:45:41.020 | and the size of the heart, the heart volume,

01:45:42.860 | and all that stuff,

01:45:43.700 | to really take control of heart rate quickly

01:45:45.900 | so that if you feel like your heart is racing too much,

01:45:48.440 | and frankly, a lot of people have a lot of

01:45:50.120 | what's called interoceptive awareness,

01:45:52.140 | especially anxious people,

01:45:53.100 | they can really sense what's going on in their body,

01:45:54.920 | other people less so, like, oh my God, my heart's beating,

01:45:57.160 | it's like ready to jump out of my chest,

01:45:58.800 | and I don't like that, I don't like that.

01:46:01.240 | Big, long exhale.

01:46:03.660 | Doesn't matter if you do it through the nose or the mouth,

01:46:05.600 | big, long exhale is going to allow you

01:46:07.080 | to slow your heart rate down.

01:46:10.120 | Let's talk about hiccups.

01:46:11.660 | Everybody experiences hiccups from time to time.

01:46:13.980 | I think most people would agree that one hiccup,

01:46:16.200 | sort of funny, two hiccups in a row is really funny,

01:46:19.960 | and three hiccups in a row

01:46:21.480 | is where it starts to be concerning,

01:46:23.080 | in part because hiccups can be kind of painful,

01:46:25.520 | and you experience pain in your gut or your lower abdomen,

01:46:28.840 | and sometimes in your chest as well,

01:46:30.520 | and it feels kind of intrusive.

01:46:31.660 | It gets in the way of having conversation

01:46:33.260 | or just sitting there and relaxing.

01:46:35.920 | Fortunately, there's a simple way to get rid of hiccups,

01:46:38.720 | and you can arrive at that simple technique

01:46:40.880 | if you understand a little bit

01:46:42.000 | about what gives rise to hiccups.

01:46:44.160 | The reason we get hiccups at all

01:46:45.560 | is because we experience a spasm of the phrenic nerve.

01:46:48.800 | The phrenic nerve, as you recall,

01:46:50.420 | is a nerve that emanates from the cervical region,

01:46:54.040 | to be specific, C3, four, and five,

01:46:56.200 | those spinal nerves go down, of course, behind the heart,

01:46:58.580 | and innervate the diaphragm, which is the muscle,

01:47:00.920 | then when it contracts, it moves down

01:47:02.320 | and allows the lungs to fill,

01:47:03.760 | and then when you relax the diaphragm,

01:47:06.320 | then the diaphragm moves up and the lungs shrink,

01:47:10.320 | or they expel air, so-called exhalation.

01:47:13.180 | Now, the phrenic nerve also has that sensory branch,

01:47:15.220 | so it's not just involved in controlling the diaphragm

01:47:17.480 | at the motor level,

01:47:18.360 | it's also sensing things deep within the diaphragm

01:47:21.080 | and in the liver as well,

01:47:22.300 | 'cause the liver sits right below the diaphragm.

01:47:24.720 | So a hiccup has that painful sensation from time to time

01:47:29.000 | because there's a rapid sensory feedback,

01:47:32.440 | or a signal, rather, of a sharp kind of sensation

01:47:35.880 | of contraction within the diaphragm,

01:47:37.800 | and that's relayed back to the brain,

01:47:39.240 | and you consciously perceive that as a little bit of pain,

01:47:42.040 | and then, of course, the hiccup is the hiccup,

01:47:44.620 | which is the spasming of the phrenic nerve

01:47:46.260 | that you experience more or less in your throat,

01:47:47.720 | but all this really is happening along the phrenic nerve

01:47:50.000 | and toward the diaphragm.

01:47:51.200 | What this all means is that if you can stop

01:47:53.000 | the phrenic nerve from spasming, you can stop hiccups.

01:47:56.880 | There are a lot of approaches that people have tried to take

01:47:58.940 | to eliminate spasming of the phrenic nerve.

01:48:01.140 | You'll hear that breathing into a bag,

01:48:03.560 | which is one way to re-ingest or re-inhale carbon dioxide

01:48:08.280 | that otherwise would be expelled out

01:48:09.620 | into the environment can help.

01:48:11.200 | That's a very indirect method.

01:48:13.140 | It rarely works, frankly,

01:48:14.900 | because it really has to do more with adjusting

01:48:16.700 | your breathing to try and adjust the activity

01:48:18.620 | of the phrenic nerve.

01:48:19.440 | It's a really roundabout way of trying to alleviate hiccups.

01:48:22.780 | Some people will experience relief from drinking

01:48:25.540 | from a glass of water from the opposite side of the glass.

01:48:27.980 | You sort of have to tilt over at the waist.

01:48:29.540 | It's a kind of messy approach.

01:48:31.140 | Again, it doesn't tend to work a lot of the time.

01:48:33.820 | For some people, it works every time,

01:48:35.060 | but for most people, it doesn't work at all.

01:48:37.500 | However, there is a technique

01:48:39.160 | that can reliably eliminate hiccups,

01:48:41.820 | and it's a technique that takes advantage

01:48:43.980 | of hyper-contracting the phrenic nerve

01:48:46.420 | over a short period of time

01:48:48.820 | so that it then subsequently relaxes

01:48:51.860 | or alleviates the spasming of the phrenic nerve.

01:48:55.020 | And that simple method is to inhale three times in a row.

01:48:59.140 | This is a very unusual pattern of breathing,

01:49:01.140 | but what it involves is taking a big, deep inhale

01:49:03.520 | through your nose.

01:49:04.780 | Then before you exhale any air,

01:49:06.620 | take a second inhale through the nose,

01:49:08.340 | however brief that inhale might be,

01:49:09.860 | and then a third, even micro or millisecond long inhale

01:49:14.580 | through your nose to get that third inhale,

01:49:16.620 | and then hold your breath for about 15 to 20 seconds,

01:49:19.500 | and then slowly exhale.

01:49:20.980 | So even though I'm not experiencing any hiccups right now,

01:49:23.640 | I will demonstrate the method for eliminating hiccups

01:49:25.500 | so that you're all clear on how to do it.

01:49:26.940 | Okay, here I go.

01:49:29.020 | [breathing in and out heavily]

01:49:32.860 | [breathing out heavily]

01:49:48.240 | Okay, so it's three inhales all through the nose,

01:49:53.580 | and it is true that that second and third inhale

01:49:56.800 | takes some physical effort to really get additional air

01:50:00.020 | into the lungs without exhaling first.

01:50:03.660 | It feels like the only way I can describe it really

01:50:05.720 | is as a sharp second and third inhale,

01:50:08.640 | 'cause you really have to engage the musculature

01:50:10.900 | of those intracostal muscles in the diaphragm

01:50:12.640 | in order to do it.

01:50:13.580 | And then that long exhale can be through the nose

01:50:15.980 | or the mouth, but I find it particularly relaxing

01:50:18.320 | or even pleasant to do it through the nose.

01:50:21.340 | This method of three inhales through the nose

01:50:23.580 | followed by a long exhale through the nose or mouth

01:50:25.980 | will eliminate hiccups right away,

01:50:28.000 | because what it does is it hyper excites the phrenic nerve

01:50:30.920 | three times in a row, a very unnatural pattern

01:50:33.080 | for the phrenic nerve to fire.

01:50:34.780 | And then it undergoes a hyperpolarization, as we call it,

01:50:39.260 | in which the phrenic nerve actually stands

01:50:41.440 | a much lower probability of getting activated again

01:50:45.640 | for some period of time afterwards.

01:50:47.380 | So it is important that you try and return

01:50:48.700 | to normal cadence of breathing

01:50:50.100 | after doing this three inhales followed by the long exhale.

01:50:52.880 | If you need to perform it a second time

01:50:54.480 | in order to eliminate hiccups,

01:50:55.820 | because they're simply not going away, that's fine.

01:50:58.160 | You can do that.

01:50:59.140 | But as far as we know, this is the most efficient

01:51:02.800 | and science supported way to eliminate hiccups.

01:51:05.820 | Now, up until now,

01:51:06.660 | I've been talking about breathing techniques

01:51:08.360 | and I've mainly focused on breathing techniques

01:51:10.420 | that emphasize the exhale,

01:51:11.660 | whether or not it's the carbon dioxide tolerance test,

01:51:14.220 | whether or not it's cyclic sighing

01:51:16.860 | or the physiological sigh that you use in real time

01:51:18.920 | to reduce stress.

01:51:20.860 | One thing that we haven't talked about so much

01:51:22.580 | is cyclic hyperventilation.

01:51:24.660 | Cyclic hyperventilation, as you recall,

01:51:26.660 | is about of 25 or so breaths,

01:51:29.620 | inhaling deeply through the nose

01:51:31.020 | and then passively exhaling,

01:51:32.300 | or sometimes actively exhaling typically through the mouth.

01:51:34.700 | So it might look like this.

01:51:35.900 | [inhales and exhales]

01:51:38.420 | That's a very active inhale through the nose

01:51:40.420 | and exhale through the mouth.

01:51:41.620 | It can also be done active inhale through the nose,

01:51:44.340 | passive exhale through the mouth, like so.

01:51:46.540 | [inhales and exhales]

01:51:49.660 | In any event, that pattern of breathing

01:51:51.780 | repeated for 10 to 25 breaths

01:51:53.540 | greatly increases levels of autonomic arousal.

01:51:55.900 | In fact, it's known to deploy adrenaline from the adrenals.

01:51:59.780 | And in our study, we had people then expel all their air,

01:52:04.660 | so breathe out, hold their breath for 15 to 30 seconds,

01:52:07.600 | and then repeat for a period of five minutes.

01:52:09.600 | That did lead to some very interesting

01:52:11.340 | and positive physiological changes

01:52:12.940 | in terms of stress mitigation,

01:52:14.820 | although not as significant as was observed

01:52:16.860 | with cyclic sighing, as I talked about earlier.

01:52:19.780 | Now, there is a lot of interest in cyclic hyperventilation

01:52:23.260 | for sake of, for instance, extending breath holds.

01:52:26.060 | This has become popular in part

01:52:27.620 | because of the so-called Wim Hof method,

01:52:29.220 | which is a method that combines breathing,

01:52:32.340 | cyclic hyperventilation,

01:52:33.420 | followed by lungs full or lungs empty breath holds,

01:52:36.880 | depending on which variant

01:52:38.180 | of the Wim Hof method one is using.

01:52:40.120 | Separately, and I really want to emphasize separately,

01:52:42.880 | the Wim Hof method also involves deliberate cold exposure,

01:52:45.460 | which, as all of you know, I'm a big fan of,

01:52:47.140 | and we've done episodes of this podcast on,

01:52:49.180 | and we have toolkits on deliberate cold exposure

01:52:50.940 | for increasing dopamine levels, epinephrine levels,

01:52:53.540 | immune system function, et cetera.

01:52:55.460 | Wim Hof method also incorporates that,

01:52:57.020 | and it has a mindfulness component.

01:52:58.780 | I do want to caution people

01:52:59.940 | that anytime you're doing cyclic hyperventilation,

01:53:02.900 | you want to be very cautious about not doing it

01:53:05.320 | in or near water,

01:53:06.580 | because it does greatly increase the risk

01:53:08.540 | of shallow water blackout.

01:53:10.260 | And that's because when you do cyclic hyperventilation,

01:53:13.140 | you are expelling,

01:53:13.980 | you're exhaling more carbon dioxide than usual.

01:53:17.060 | And what I haven't told you yet

01:53:18.580 | is that the trigger to breathe

01:53:20.980 | is actually an increase in carbon dioxide.

01:53:24.540 | What I mean by that is you have a small set of neurons

01:53:26.940 | in your brainstem that can detect when carbon dioxide levels

01:53:30.160 | in your bloodstream reach a certain level,

01:53:31.860 | and when they reach that level,

01:53:33.300 | they trigger the gas reflex and/or the hunger for breathing.

01:53:37.880 | In other words, we don't breathe because we crave oxygen,

01:53:40.740 | although we do need oxygen, of course, in order to survive,

01:53:44.140 | and for our brain to function

01:53:45.180 | and our bodily organs to function,

01:53:46.980 | but our brain is wired such that it has a threat sensor,

01:53:51.660 | which is carbon dioxide levels are getting too high,

01:53:53.660 | and that's what triggers the motor reflex to breathe

01:53:57.500 | and to, in some cases, gasp for air,

01:53:59.500 | depending on how starved for air we are.

01:54:02.160 | So if you do cyclic hyperventilation,

01:54:04.140 | whether or not it's Wim Hof method

01:54:05.780 | or whether or not it's Tummo method,

01:54:07.820 | again, these things are similar.

01:54:09.020 | They're not exactly the same.

01:54:10.080 | There are other breathing methods

01:54:11.420 | that incorporate cyclic hyperventilation.

01:54:13.780 | What you're doing is you're getting rid

01:54:14.820 | of a lot of carbon dioxide,

01:54:16.060 | and therefore you're removing the impulse

01:54:18.700 | or lowering the impulse to breathe

01:54:20.060 | so that when you enter that breath hold phase

01:54:21.700 | after the hyperventilation,

01:54:23.060 | it's a much longer period of time

01:54:24.900 | before you feel the anxiety and the hunger

01:54:27.400 | and the impulse to breathe.

01:54:28.860 | That's one of the real benefits of any technique

01:54:31.260 | that incorporates cyclic hyperventilation

01:54:33.580 | is that rather than reduce your stress level in real time,

01:54:37.260 | it actually does the opposite.

01:54:38.540 | It increases your stress level.

01:54:39.940 | It increases your level of autonomic arousal,

01:54:42.540 | but you're doing it deliberately.

01:54:44.220 | And then during those breath holds,

01:54:45.860 | what's happening is you have a lot of adrenaline

01:54:48.220 | circulating in your system

01:54:50.020 | because of the way that hyperventilation

01:54:51.980 | triggers the release of adrenaline from your adrenal glands.

01:54:54.840 | It also triggers the release of epinephrine,

01:54:56.620 | which is the same as adrenaline

01:54:58.180 | from a little brain area called locus coeruleus,

01:55:00.140 | which makes you feel more alert.

01:55:01.460 | And then during those breath holds

01:55:03.760 | and in the subsequent rounds of cyclic hyperventilation,

01:55:07.080 | people experience what it is

01:55:08.980 | to have a lot of adrenaline in their system,

01:55:10.820 | but they are controlling the release of that adrenaline,

01:55:13.800 | which is far and away different than when life events

01:55:16.760 | are triggering that adrenaline.

01:55:18.340 | So what it really is

01:55:19.180 | is a form of self-induced stress inoculation.

01:55:22.060 | And I do think there are benefits

01:55:23.580 | to practicing cyclic hyperventilation

01:55:25.440 | because it does allow you to learn

01:55:27.120 | how to self deploy adrenaline and epinephrine

01:55:29.680 | from locus coeruleus and from the adrenals,

01:55:31.740 | or I got that backwards,

01:55:33.020 | adrenaline from your adrenals

01:55:34.420 | and epinephrine from locus coeruleus.

01:55:36.480 | And it allows you to explore

01:55:38.580 | what it is to maintain calm state of mind and body

01:55:42.280 | when you have a lot of adrenaline in your system,

01:55:44.820 | which certain studies are starting to show

01:55:47.380 | can allow people to be able to lean

01:55:49.820 | into the stressful aspects of life.

01:55:51.660 | And let's be honest, life is stressful in any event.

01:55:54.420 | Now we're all going to experience stress

01:55:56.100 | at some point or another.

01:55:57.220 | And when we do,

01:55:58.780 | we want to make sure that we're not overtaken

01:56:00.820 | by the release of adrenaline from the adrenals,

01:56:03.300 | that sudden surge of epinephrine from locus coeruleus.

01:56:06.120 | So doing cyclic hyperventilation,

01:56:07.960 | maybe one or two times per week,

01:56:09.700 | again, 25 breaths, active inhale, passive or active exhale.

01:56:14.320 | Do expect to feel tingly

01:56:15.900 | because of that reduction in carbon dioxide

01:56:17.640 | from exhaling so much.

01:56:19.060 | Do expect to feel a little bit agitated.

01:56:21.360 | Be very careful doing this

01:56:22.640 | if you're somebody who has anxiety attacks

01:56:24.320 | or somebody who has panic attacks or disorders of any kind.

01:56:27.500 | But if you don't and you want to explore this,

01:56:28.960 | you'll notice you start to feel really ramped up.

01:56:31.680 | And then during the breath holds,

01:56:33.260 | which again can be done by exhaling and stopping

01:56:36.800 | for some period of time, 15, maybe even 60 seconds,

01:56:40.060 | is a time in which you can explore

01:56:41.520 | how to remain mentally calm.

01:56:43.700 | Some people even choose to do math problems

01:56:45.560 | or think of things in a kind of structured way

01:56:47.660 | while they have a lot of these hormone neurotransmitters

01:56:51.500 | circulating at high levels in their system.

01:56:54.380 | In other words, as a way to learn to manage your mind

01:56:57.860 | and body under conditions of stress.

01:56:59.920 | Now, if you are somebody

01:57:00.880 | who's using deliberate cold exposure,

01:57:02.420 | either cold showers or ice baths or cold immersion,

01:57:06.740 | I often get asked how best to breathe

01:57:09.660 | during those different types of activities.

01:57:12.240 | Really, there's no best way to breathe.

01:57:13.980 | Although if you wanted to turn those activities

01:57:16.780 | into their own form of stress inoculation,

01:57:19.120 | again, please don't use cyclic hyperventilation.

01:57:21.920 | It's dangerous.

01:57:22.760 | I don't recommend it whatsoever.

01:57:24.640 | But you can try to actively slow your breathing.

01:57:28.400 | That is to make sure

01:57:29.740 | that you're engaging in rhythmic breathing.

01:57:32.020 | Now, up until now,

01:57:33.020 | I've said that rhythmic breathing is the default.

01:57:35.300 | Pre-bot singer nucleus controlling rhythmic breathing

01:57:37.700 | is the default.

01:57:38.540 | And that doubling up on inhales and exhales

01:57:40.900 | is something that happens when you deliberately take over

01:57:44.380 | the action of pre-bot singer complex.

01:57:46.700 | Now, that's true 99% of the time.

01:57:49.620 | However, there are certain conditions

01:57:51.220 | such as conditions of heightened state of emotional arousal.

01:57:54.740 | Right, if you think about somebody who's been crying,

01:57:56.900 | oftentimes they'll do the double inhale exhale

01:57:59.700 | that says, or triple inhales,

01:58:01.540 | or if somebody is very, very afraid, it's all inhales.

01:58:04.300 | Okay, so it does sometimes happen spontaneously.

01:58:06.860 | Actually, when we get into very cold water,

01:58:09.340 | there's a very robust decrease

01:58:12.040 | in the activation of the prefrontal cortex,

01:58:13.820 | which is the area of brain real estate

01:58:16.020 | right behind the forehead that controls structured thinking,

01:58:18.780 | your ability to reason and make sense of what's going on.

01:58:22.320 | If you get into really cold water,

01:58:23.420 | you should not expect that brain region to work

01:58:25.620 | or at least not work very well at all

01:58:27.380 | for the first 20 or 30 seconds

01:58:28.880 | that you're in the cold water.

01:58:30.740 | From the time you get into cold water,

01:58:33.120 | 'cause here we're talking about deliberate cold exposure,

01:58:35.640 | I encourage you to try and control your breathing

01:58:38.220 | and make it rhythmic.

01:58:39.260 | That is inhales, follow exhales, follow inhales, follow exhales

01:58:42.520 | even if they have to be fast, inhale, exhale, inhale, exhale.

01:58:45.280 | Why?

01:58:46.120 | Because the default,

01:58:47.580 | when we get into a stressful circumstance,

01:58:49.920 | emotionally or physically stressful circumstance,

01:58:52.100 | is that rhythmic breathing stops

01:58:54.660 | and that parafacial nucleus takes over

01:58:56.800 | and it's, and it's that kind of panicky mode.

01:59:00.260 | And by simply controlling our breath,

01:59:02.900 | again, even if it's fast,

01:59:05.220 | from inhale to exhale and making sure

01:59:07.280 | that we're alternating inhales and exhales rhythmically,

01:59:09.780 | and what you'll find is that you'll be able to navigate

01:59:11.720 | that what would otherwise be a very stressful circumstance

01:59:15.320 | and make it less stressful or maybe even pleasant.

01:59:18.920 | And that skill definitely translates

01:59:21.580 | to other aspects of life in which, you know,

01:59:23.420 | you're hit square in the face with something stressful,

01:59:25.540 | you'll notice your breathing and your pattern of breathing

01:59:27.840 | switching to multiple inhales or, you know,

01:59:31.260 | breath holding essentially departing from rhythmic breathing

01:59:34.460 | and by quickly returning to rhythmic breathing

01:59:36.580 | and maybe even trying to slow the breathing

01:59:38.220 | and extend those exhales,

01:59:39.640 | you'll find that you can very quickly calm down.

01:59:42.600 | Next, I'd like to discuss what I find to be

01:59:44.220 | an absolutely fascinating topic.

01:59:46.120 | It's also one that's highly useful in the world,

01:59:49.000 | which is how your specific patterns of breathing

01:59:51.740 | relate to your ability to learn and to remember information,

01:59:55.140 | how we can modulate fear and a number of other aspects

01:59:58.180 | of how your brain functions.

02:00:00.340 | This is a literature that's been reviewed recently

02:00:02.740 | and a lot of exquisite detail in a beautiful review

02:00:06.180 | by Jack Feldman, who I mentioned earlier,

02:00:08.000 | one of the pioneers of the neuroscience of breathing.

02:00:11.540 | The title of the review is "Breathing Rhythm and Pattern

02:00:14.420 | and Their Influence on Emotion."

02:00:16.100 | Again, we'll provide a link to this review

02:00:18.580 | in the show note captions.

02:00:19.880 | This review includes discussion of several studies,

02:00:23.900 | one in particular that I'll get into in a bit of detail

02:00:28.460 | that describes the following.

02:00:30.660 | Right now, I just want you to breathe regularly,

02:00:33.980 | meaning rhythmically.

02:00:35.220 | You can inhale and exhale through your mouth

02:00:37.100 | or through your nose.

02:00:37.940 | I'd prefer that you do it through your nose

02:00:39.420 | because nasal breathing,

02:00:40.860 | unless you need to breathe through your mouth

02:00:42.940 | because of heart exercise or eating or talking

02:00:45.300 | is always going to be the better way to go.

02:00:47.620 | Nasal breathing improves the aesthetic of your face.

02:00:50.360 | That's been shown.

02:00:51.200 | We'll talk about that just briefly in a few minutes.

02:00:52.940 | Nasal breathing improves the amount of oxygen

02:00:55.340 | you can bring into your system, et cetera, et cetera.

02:00:57.020 | Okay, so just breathe, inhale, exhale, inhale, exhale.

02:00:59.940 | And know that during your exhales, your pupil,

02:01:04.780 | that is the pupil of your eye, is getting bigger.

02:01:07.780 | And as you exhale, it's getting smaller.

02:01:12.080 | In addition, when you inhale,

02:01:15.120 | your reaction time to anything that happens around you,

02:01:18.260 | a car swerving in front of you,

02:01:19.680 | something that you might detect in the periphery

02:01:21.620 | of your vision or here off in the distance

02:01:24.020 | increases significantly compared to when you're exhaling.

02:01:27.260 | In addition, when you are inhaling,

02:01:30.540 | your ability to remember things,

02:01:32.600 | especially things that take a bit of effort to remember

02:01:35.820 | and your ability to learn new information

02:01:38.620 | is significantly greater than it is when you're exhaling.

02:01:42.420 | Now, as you hear all that, you're probably thinking,

02:01:44.180 | okay, how do I just inhale?

02:01:45.460 | Well, of course, that's not going to be the best approach.

02:01:47.040 | You need to exhale as well

02:01:49.300 | for all the reasons you now are well aware of.

02:01:52.220 | But what these findings really illustrate,

02:01:54.140 | and I should mention these findings

02:01:55.200 | are all carried out in humans, all right?

02:01:57.100 | So these relate to some stuff in animal studies,

02:01:59.340 | but what I just described has been shown

02:02:01.220 | in human studies consistently.

02:02:03.940 | When we inhale, and in particular,

02:02:06.600 | when we inhale through our nose,

02:02:08.700 | our brain is not functioning in the same way

02:02:12.020 | as when we exhale.

02:02:13.180 | Now, that doesn't mean that our brain is functioning

02:02:15.080 | in a deficient way when we exhale.

02:02:17.720 | It just doesn't function as well

02:02:19.920 | as it relates to memory retrieval, memory formation,

02:02:23.280 | and some other aspects of cognition.

02:02:25.540 | Now, you might be asking, why in the world would this be?

02:02:28.660 | Well, I wasn't consulted at the design phase,

02:02:32.140 | and anyone that tells you that they were,

02:02:34.120 | you should back away from quickly.

02:02:35.980 | But one reasonable explanation

02:02:37.860 | for why our brain functions better,

02:02:39.320 | at least in the context of what I just talked about,

02:02:41.600 | when we inhale is because the olfactory system

02:02:46.600 | is actually the most ancient sensory system

02:02:49.680 | of all the sensory systems we have.

02:02:51.540 | So before vision, before audition, before touch,

02:02:54.900 | before all of that,

02:02:55.900 | the olfactory system is the most ancient system.

02:02:58.900 | And the olfactory system, of course,

02:03:00.620 | is designed to detect chemicals in the environment.

02:03:03.260 | And so if you imagine an early organism

02:03:06.440 | that perhaps we evolved from, or perhaps we didn't,

02:03:08.980 | but nonetheless that we share some features of,

02:03:11.140 | at least in terms of olfactory function,

02:03:13.260 | in order to get that chemical information into the brain,

02:03:18.240 | we need to inhale.

02:03:19.260 | We need to bring that information in.

02:03:20.460 | Now, for aquatic animals,

02:03:21.560 | they could take it in through water,

02:03:23.160 | but for animals that are terrestrial, that live on land,

02:03:27.140 | they would have to get it through the air.

02:03:29.820 | So inhalation, we know,

02:03:32.020 | activates certain regions of the so-called piriform cortex.

02:03:34.940 | These are areas of the neocortex that are more ancient,

02:03:37.760 | as well as increasing the activity of brain areas,

02:03:40.700 | such as the hippocampus,

02:03:42.080 | which is a brain area involved in learning and memory.

02:03:44.280 | In fact, one of the studies

02:03:45.340 | that illustrates this most beautifully

02:03:47.600 | is a study that was published in the Journal of Neuroscience

02:03:50.400 | in 2016.

02:03:51.460 | By the way, Journal of Neuroscience is a very fine journal.

02:03:53.980 | And the title of this paper is

02:03:55.420 | Nasal Respiration in Transhuman Limbic Oscillations

02:03:58.740 | and Modulates Cognitive Function.

02:04:00.660 | This is a paper that followed up on an earlier paper

02:04:03.480 | that showed that when people breathe in through their nose,

02:04:07.520 | their recognition and their discrimination

02:04:10.140 | of different odors was far greater

02:04:12.460 | than when they breathe in through their mouth.

02:04:15.000 | Now, that result was interesting,

02:04:16.300 | but it was also sort of a duh

02:04:17.740 | because you smell things with your nose, not your mouth.

02:04:20.040 | You taste things with your mouth

02:04:21.120 | and you speak with your mouth,

02:04:22.000 | and there are a bunch of other things

02:04:22.840 | you can do with your mouth.

02:04:23.660 | But nonetheless, that study pointed to the idea

02:04:28.640 | that the brain is different during nasal inhalations

02:04:32.820 | versus nasal exhalations

02:04:35.840 | versus mouth inhalations versus exhalations.

02:04:38.960 | What it basically showed is that the brain

02:04:40.640 | ramps up its levels of activity

02:04:42.500 | and that signal to noise that we talked about earlier,

02:04:45.240 | if you recall, that ability for the brain

02:04:47.200 | to detect things in the environment

02:04:49.400 | is increased during inhalations.

02:04:51.960 | But because that earlier study focused on smell,

02:04:55.280 | on olfaction, there was a bit of a confound there.

02:04:57.960 | It was hard to separate out the variable.

02:04:59.460 | So this paper, the one I just mentioned,

02:05:01.200 | Nasal Respiration in Transhuman Limbic Oscillations

02:05:03.420 | and Modulates Cognitive Function,

02:05:05.320 | did not look at detection of odors.

02:05:08.460 | Rather, it looked at things like reaction time or fear.

02:05:12.240 | And basically what it found is that reaction time

02:05:15.920 | is greatly reduced when people are inhaling.

02:05:19.760 | So they had people look at fearful stimuli.

02:05:21.500 | They looked at their reaction time to fearful stimuli.

02:05:23.440 | In other words, their ability to detect

02:05:24.860 | certain kinds of stimuli.

02:05:26.120 | And they were given a lot of different kinds of stimuli.

02:05:27.780 | So they had to be able to discriminate

02:05:29.980 | between one sort of, oops, excuse me,

02:05:31.680 | one, by the way, folks, for those listening,

02:05:33.480 | I just bumped the microphone, getting rather animated here.

02:05:36.640 | What these subjects had to do was detect

02:05:39.160 | one type of stimulus versus another stimulus

02:05:41.840 | that they were being exposed to.

02:05:43.800 | And what they found is if people were inhaling

02:05:46.280 | as that fear-inducing stimulus was presented,

02:05:49.040 | their reaction time to notice it was much, much faster.

02:05:51.480 | And they related that to patterns of brain activity.

02:05:54.560 | And they were able to do that

02:05:55.840 | because they were actually recording from the brain directly

02:05:59.080 | from beneath the skull.

02:06:00.040 | And they were able to do that because they had some patients

02:06:02.440 | that had intracranial electrodes embedded in their brain

02:06:04.840 | for sake of trying to detect epileptic seizures.

02:06:07.580 | So there's a lot to this study

02:06:09.920 | and a lot that we could discuss,

02:06:11.640 | but the basic takeaway is that when people are inhaling,

02:06:16.400 | that is when they're drawing air in

02:06:18.760 | through their nose in particular,

02:06:21.120 | their ability to detect what's going on

02:06:23.480 | in the world around them is greatly enhanced

02:06:26.080 | and not just for fear, but also for surprise of all sorts.

02:06:30.400 | So when people are inhaling,

02:06:32.160 | their ability to detect novel stimuli,

02:06:34.360 | things that are unexpected or that are unusual

02:06:38.360 | in their environment is significantly increased.

02:06:41.040 | Again, we'll put a link to this study as well.

02:06:42.600 | I find it to be one of the more interesting studies

02:06:44.340 | in this realm.

02:06:45.200 | Although there are now many additional studies

02:06:47.720 | that support this statement that I made earlier,

02:06:50.200 | which is that during inhalation, also called inspiration,

02:06:53.880 | there are a number of very fast physiological changes,

02:06:56.380 | such as changes in pupil diameter,

02:06:58.320 | changes in the activity of the hippocampus,

02:07:00.400 | this memory encoding and retrieval area of the brain

02:07:03.200 | and other areas of the brain.

02:07:04.640 | So what's the tool takeaway from this?

02:07:07.040 | If you are sitting down to read or research

02:07:10.480 | or study or you really want to learn some information,

02:07:13.580 | maybe you're listening to a podcast

02:07:15.600 | or some other sorts of information that you want to retain,

02:07:19.260 | it actually makes sense to increase the duration

02:07:23.280 | or the intensity of your inhales as you do that.

02:07:26.600 | The more that you're inhaling relative to exhaling

02:07:29.240 | in terms of duration,

02:07:30.620 | the more that your brain is in this focused mode

02:07:33.520 | and this mode of being able to access

02:07:35.360 | and retrieve information better.

02:07:37.440 | Now there's one caveat to this that I think is important

02:07:40.200 | because I know a number of people listen to this podcast

02:07:42.400 | for sake of gleaning tools,

02:07:43.540 | not just for cognitive enhancement,

02:07:44.840 | but for physical enhancement.

02:07:46.460 | It turns out that when you are inhaling air,

02:07:50.440 | you're actually less able, or I should say less efficient

02:07:55.220 | at generating voluntary movements.

02:07:57.680 | Now that might come as a surprise.

02:07:59.600 | You know, up until now,

02:08:00.820 | we've basically been talking about inhalation is great,

02:08:02.920 | almost to the point where you wonder like,

02:08:04.120 | is exhalation good for anything, right?

02:08:05.840 | You don't want to over-breathe

02:08:06.720 | and kick out too much carbon dioxide.

02:08:08.000 | Well, of course, exhalation is great for things.

02:08:09.720 | In fact, if you're somebody that's played baseball

02:08:12.080 | or softball, what are you told?

02:08:14.300 | That you should exhale on the swing

02:08:15.920 | to generate the maximum amount of power.

02:08:18.060 | If you're somebody who has done martial arts of any kind,

02:08:21.360 | it was traditional Western boxing.

02:08:23.240 | As you strike, that's where people typically do the hiya,

02:08:26.920 | laying the sort of classic karate type thing.

02:08:28.880 | That's more of a movie thing.

02:08:29.920 | I don't know whether or not people actually use the hiya,

02:08:32.500 | but in boxing, oftentimes people will do the shh.

02:08:35.040 | You know, they'll do a rapid exhalation,

02:08:36.920 | a forceful exhalation, keeping in mind, again,

02:08:41.040 | that inhales typically are active.

02:08:43.420 | They engage the diaphragmatic muscle.

02:08:45.820 | They engage those intercostal muscles,

02:08:48.000 | whereas exhales tend to be passive

02:08:49.640 | unless we take active control of the exhale.

02:08:51.960 | And indeed, our ability to generate fast, directed,

02:08:55.860 | so-called volitional voluntary movements

02:08:58.640 | is greatly enhanced if we do them during the exhale,

02:09:02.280 | not the inhale.

02:09:03.720 | Now, with all of that said, I haven't yet really talked

02:09:07.600 | about mouth versus nasal breathing.

02:09:09.500 | And it really can be a fairly short discussion

02:09:11.820 | because what abundant data now show

02:09:15.760 | and has been beautifully described

02:09:17.280 | in the book called "Jaws, a Hidden Epidemic,"

02:09:19.560 | this is a book that was written by Paul Ehrlich

02:09:21.560 | and Sandra Kahn, my colleagues

02:09:22.820 | at Stanford School of Medicine.

02:09:23.880 | It has an introduction and a forward from Jared Diamond

02:09:27.520 | and from the great Robert Sapolsky,

02:09:29.000 | so some real heavy hitters on this book.

02:09:30.940 | What that book really describes is that

02:09:33.540 | whenever possible, meaning unless you're speaking or eating

02:09:36.640 | or you're exercising or other activities require

02:09:39.420 | some change in your pattern of breathing,

02:09:41.540 | we should really all be striving to breathe

02:09:43.760 | through our nose, not through our mouth.

02:09:46.120 | And that relates to the increased resistance

02:09:48.260 | to breathing through the nose we talked about earlier.

02:09:50.000 | Again, I'll say it a third time,

02:09:51.920 | that increased resistance through the nose allows you

02:09:54.440 | to inflate your lungs more, not less.

02:09:56.240 | The other thing that breathing through your nose

02:09:57.620 | allows you to do is it both warms and moisturizes the air

02:10:01.320 | that you bring into your lungs,

02:10:02.380 | which is more favorable for lung health

02:10:04.820 | than breathing through the mouth.

02:10:06.680 | Hard breathing through the mouth

02:10:08.040 | or simply mouth breathing at all is actually quite damaging

02:10:11.080 | or can be, I should say, quite damaging

02:10:13.180 | to some of the respiratory functions of your lungs.

02:10:15.160 | That of course does not mean that you shouldn't breathe hard

02:10:17.720 | through your mouth when you're running or sprinting

02:10:19.280 | or exercising hard, but you don't want mouth breathing

02:10:22.320 | to be the chronic default pattern that you follow.

02:10:25.560 | Nasal breathing is the best pattern of breathing to follow

02:10:28.720 | as a default state.

02:10:30.380 | Another aspect of nasal breathing

02:10:31.840 | that's really beneficial is that the gas,

02:10:34.020 | nitric oxide, is actually created in the nasal passages.

02:10:37.440 | It's a gas that can cause relaxation of the smooth muscles

02:10:42.440 | that relate to the vasculature, not just of your nose,

02:10:45.760 | but of your brain and for all the tissues of your body.

02:10:48.720 | This is why nasal breathing and not mouth breathing

02:10:52.200 | is great for when you want to relieve congestion.

02:10:54.680 | So a lot of these things seem counterintuitive, right?

02:10:56.640 | Your nose is stuffed,

02:10:57.480 | so that mainly makes people breathe through their mouth,

02:11:00.460 | but it turns out that breathing through your nose

02:11:02.040 | will allow some dilation of the vasculature,

02:11:05.600 | more blood flow, dilation of the nasal passages,

02:11:08.440 | and delivery of nitric oxide to all the tissues of your body

02:11:11.840 | and that dilation of the small capillaries

02:11:14.760 | that innervate essentially every organ of your body,

02:11:17.900 | allow the delivery of more nutrients

02:11:19.540 | and the removal of carbon dioxide and other waste products

02:11:24.160 | from those tissues more readily

02:11:25.740 | than if you're not getting enough, excuse me,

02:11:27.900 | nitric oxide into your system.

02:11:29.620 | Okay, so a lot of reasons to be a nasal breather.

02:11:31.880 | If you want to check out that book, "Jaws,"

02:11:33.720 | "Hidden Epidemics," it's a terrific read,

02:11:35.580 | and it also shows some absolutely striking pictures,

02:11:38.280 | twin studies and so forth,

02:11:39.680 | and some before and afters of people

02:11:41.640 | and the aesthetic changes that they experienced

02:11:44.120 | when they shifted from being a mouth breather

02:11:46.480 | to a nose breather.

02:11:47.980 | These are striking examples

02:11:49.760 | that have been observed over and over again.

02:11:51.660 | When people mouth breathe,

02:11:53.000 | there's an elongation of the jaw,

02:11:55.240 | droopiness of the eyelids,

02:11:57.040 | and the entire jaw structure really changes

02:11:59.440 | in ways that are not aesthetically favorable.

02:12:02.040 | Fortunately, when people switch

02:12:03.580 | to becoming nasal breathers,

02:12:05.120 | and of course that takes some encouragement

02:12:07.600 | either by mouth taping

02:12:08.800 | or doing their cardiovascular exercise with mouth closed

02:12:12.240 | or by doing the sorts of exercises

02:12:13.960 | that we talked about earlier,

02:12:15.100 | when they switch to becoming nasal breathers by default,

02:12:18.280 | the aesthetic changes that occur

02:12:20.040 | are very dramatic and very favorable,

02:12:23.120 | including sort of elevation of the eyebrows,

02:12:26.480 | not in an artificial sense

02:12:28.040 | or in a kind of outrageous way,

02:12:29.900 | but elevation of the cheekbones,

02:12:31.440 | sharpening of the jaw,

02:12:32.880 | and most notably improvements of the teeth

02:12:35.240 | and the entire jaw structure.

02:12:36.760 | In fact, one simple test

02:12:38.240 | of whether or not you can be an efficient nasal breather

02:12:41.120 | and whether or not you've been nasal breathing efficiently

02:12:43.680 | or most of the time in the past,

02:12:44.940 | or whether or not you've been relying

02:12:45.920 | more on mouth breathing,

02:12:47.860 | that was described in the book "Jaws"

02:12:49.240 | is you should be able to close your mouth

02:12:51.880 | and breathe only through your nose.

02:12:54.160 | Again, this is at rest,

02:12:55.000 | not during exercise necessarily,

02:12:56.800 | though you might do it during exercise,

02:12:58.420 | but close your mouth,

02:12:59.660 | put your tongue on the roof of your mouth,

02:13:02.080 | and it should fit behind your teeth,

02:13:04.000 | and you should be able to nose breathe in that position.

02:13:08.400 | And many people won't be able to do that,

02:13:10.440 | but fortunately, as I mentioned earlier,

02:13:12.280 | if you nasal breathe,

02:13:13.840 | that is you deliberately nasal breathe when at rest

02:13:16.640 | for some period of time,

02:13:18.240 | you will experience an increased ability to nasal breathe,

02:13:21.560 | and you should also experience some addition of space

02:13:25.080 | within the palate of your mouth

02:13:27.860 | to allow your tongue to sit more completely

02:13:30.080 | on the roof of your mouth.

02:13:31.020 | This is especially true for children

02:13:32.440 | that perform this technique.

02:13:33.400 | Again, I refer you to the book "Jaws, A Hidden Epidemic."

02:13:35.840 | It's an absolutely spectacular book.

02:13:37.200 | You can also just look online

02:13:39.040 | before and after "Jaws, Hidden Epidemic"

02:13:40.920 | and look at some of the changes in facial structure

02:13:43.060 | that occur when people move from mouth to nasal breathing,

02:13:46.220 | and it's really quite striking.

02:13:48.160 | So during today's episode, per always,

02:13:50.900 | we covered a lot of information.

02:13:52.200 | First, we talked about the mechanical aspects of breathing,

02:13:55.240 | the lungs, the diaphragm, the trachea, and so forth.

02:13:59.160 | We also talked about the chemical aspects of breathing,

02:14:01.200 | that really, breathing is a way

02:14:02.920 | that we bring oxygen to ourselves

02:14:04.960 | and that we get the correct levels,

02:14:07.140 | or I should say we maintain the correct levels

02:14:09.400 | of carbon dioxide in our system,

02:14:11.000 | neither too much nor too little,

02:14:13.180 | in order to allow oxygen to do its magic

02:14:16.000 | and to allow carbon dioxide to do its magic,

02:14:18.660 | because as you learned during today's episode,

02:14:20.260 | carbon dioxide is not just a waste by-product.

02:14:23.060 | It has very critical physiological functions.

02:14:25.800 | You need to have enough of it around,

02:14:27.560 | and therefore you don't want to over-breathe,

02:14:29.820 | especially at rest.

02:14:31.480 | We talked about a tool to measure

02:14:32.940 | how well you manage carbon dioxide,

02:14:34.700 | the so-called carbon dioxide tolerance test,

02:14:37.540 | and various exercises that you can use simply by breathing

02:14:41.640 | to decrease your stress in real time,

02:14:44.360 | decrease your stress chronically around the clock,

02:14:46.880 | obviously that's a good thing,

02:14:47.900 | improve sleep, improve mood,

02:14:49.660 | how to increase breath hold times

02:14:51.920 | and why you might want to do that,

02:14:53.620 | also how to eliminate hiccups.

02:14:55.820 | We talked about how to breathe

02:14:57.240 | in order to eliminate the side stitch or side cramp

02:14:59.480 | that you might experience during exercise,

02:15:01.520 | and how to breathe in order to improve learning and memory,

02:15:04.360 | reaction time, and various other aspects

02:15:07.080 | of cognitive and physical function.

02:15:09.320 | I do realize it's a lot of information, but as always,

02:15:12.820 | I try and give you information that is clear,

02:15:15.640 | hopefully interesting as well,

02:15:17.360 | and actionable toward a number of different end points.

02:15:20.460 | So if you're somebody that's just now

02:15:22.100 | starting to think about the application of breath work,

02:15:24.420 | I would encourage you to please, yes,

02:15:26.740 | do the carbon dioxide tolerance test.

02:15:28.380 | That will give you some window into how well

02:15:30.360 | or how poorly you're managing breathing.

02:15:31.940 | And then here's the great news.

02:15:33.740 | The great news is that breath work,

02:15:35.740 | that is deliberate respiration practices,

02:15:38.260 | are very effective at creating change very quickly.

02:15:42.020 | In some cases, such as the use of the physiological psi

02:15:44.980 | or cyclic hyperventilation,

02:15:46.820 | those changes can be experienced the first time

02:15:49.040 | and every time, because again, these are not hacks.

02:15:52.000 | These are aspects of your breathing apparati,

02:15:55.100 | including the mechanical stuff and the neural stuff

02:15:57.340 | and the gas exchange stuff, all of which you were born with,

02:16:00.940 | and that are available to you at any moment.

02:16:02.880 | So all you really have to do is explore them

02:16:05.580 | and deploy them as you feel necessary.

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02:18:35.360 | Once again, I'd like to thank you for today's discussion

02:18:37.340 | all about the biology and application of breathing.

02:18:40.620 | And last, but certainly not least,

02:18:42.780 | thank you for your interest in science.

02:18:44.620 | [upbeat music]

02:18:47.200 | (gentle music)

How to Breathe Correctly for Optimal Health, Mood, Learning & Performance | Huberman Lab Podcast

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