Supercharge Exercise Performance & Recovery with Cooling

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

00:00:02.280 | where we discuss science and science-based tools

00:00:04.900 | for everyday life.

00:00:05.920 | I'm Andrew Huberman,

00:00:10.680 | and I'm a professor of neurobiology and ophthalmology

00:00:13.760 | at Stanford School of Medicine.

00:00:15.840 | This podcast is separate from my teaching

00:00:17.580 | and research roles at Stanford.

00:00:19.440 | It is, however, part of my desire and effort

00:00:21.620 | to bring you zero cost to consumer information

00:00:23.720 | about science and science-related tools

00:00:25.840 | to the general public.

00:00:27.540 | In keeping with that theme,

00:00:28.680 | I'd like to thank the sponsors of today's podcast.

00:00:31.740 | Our first sponsor is Inside Tracker.

00:00:34.460 | Inside Tracker is a personalized nutrition platform

00:00:37.100 | that analyzes data from your blood and DNA

00:00:39.600 | to help you better understand your body

00:00:41.320 | and help you reach your health goals.

00:00:43.760 | I've long been a believer in getting regular blood tests.

00:00:46.940 | And the simple reason for that

00:00:48.660 | is that so many of the factors that impact our immediate

00:00:52.080 | and long-term health and wellbeing

00:00:53.920 | can only be analyzed from blood.

00:00:56.200 | And now with the advent of modern DNA tests,

00:00:58.540 | you can get additional layers of information

00:01:00.780 | that can really support your understanding

00:01:02.460 | about what's going on deep under the hood, so to speak,

00:01:06.460 | inside your body and brain and what to do about it.

00:01:10.620 | And I think that's really where Inside Tracker

00:01:12.240 | sets itself apart from other similar tests.

00:01:15.660 | What Inside Tracker offers is, first of all,

00:01:18.300 | they make the tests very easy.

00:01:19.860 | They can come to your home to take your blood and DNA test,

00:01:22.200 | or you can go to a testing center nearby you.

00:01:25.260 | Then you get the information back,

00:01:26.840 | and rather than just getting information

00:01:28.640 | about whether or not the levels of various things

00:01:30.520 | are high or low,

00:01:32.220 | you also get to find out what to do about it.

00:01:35.200 | So it offers directives related to nutrition,

00:01:37.840 | to exercise and so forth.

00:01:40.120 | It really allow you to be in control of your overall health,

00:01:44.080 | both where you are now and its long-term trajectory.

00:01:47.800 | With Inside Tracker, they also have something

00:01:50.920 | which is it can give you a readout of your inner age.

00:01:53.600 | They have something called the inner age test

00:01:55.200 | that really compares your biological age

00:01:57.440 | to your chronological age,

00:01:58.620 | something that's of extreme importance and interest

00:02:00.840 | because it has to do with lifespan or predicted lifespan.

00:02:04.320 | If you'd like to try Inside Tracker,

00:02:05.800 | you can visit insidetracker.com/huberman.

00:02:08.600 | And if you do that, you'll get 25% off

00:02:10.880 | any of Inside Tracker's plans.

00:02:12.640 | Use the code Huberman at checkout.

00:02:14.800 | That's insidetracker.com/huberman

00:02:16.960 | to get 25% off any of Inside Tracker's plans

00:02:19.960 | and use the code Huberman at checkout.

00:02:22.520 | Today's episode is also brought to us by Helix Sleep.

00:02:25.560 | Helix Sleep is a company that makes mattresses and pillows

00:02:28.280 | ideally suited to your sleep needs.

00:02:30.760 | I've been sleeping on a Helix mattress

00:02:32.400 | for the last six months.

00:02:33.600 | And I can honestly say it's the best sleep

00:02:35.800 | that I've ever gotten.

00:02:37.360 | Helix Sleep has a quiz that can match you

00:02:39.440 | to the ideal mattress and pillows for you.

00:02:42.840 | It's a quiz that takes just about two minutes,

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00:02:47.600 | or your back, on your stomach, or maybe you don't know

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00:02:56.400 | At the end of that quiz, it matches you

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00:03:01.160 | For me, it matched me to the DUSK, D-U-S-K,

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00:03:06.600 | nor too soft.

00:03:07.920 | And I really love the mattress.

00:03:09.200 | As I mentioned, I've been sleeping terrifically well

00:03:11.340 | ever since I got that mattress.

00:03:13.280 | If you're interested in upgrading your mattress,

00:03:14.980 | you can go to helixsleep.com/huberman,

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00:03:42.620 | Today's episode is also brought to us by Theragun.

00:03:45.720 | Theragun is a handheld percussive therapy device

00:03:48.200 | that releases deep muscle tension.

00:03:50.660 | I first learned about Theragun on a lab expedition.

00:03:53.820 | We were actually headed out to Ocean

00:03:55.780 | where we were doing diving with great white sharks,

00:03:58.320 | filming those for our VR fear experiments in the laboratory,

00:04:02.240 | and it was very long days of carrying Pelican cases.

00:04:05.720 | Those are cases, these hard plastic cases with equipment.

00:04:09.080 | It was diving.

00:04:10.440 | We were all sore and tired all the time,

00:04:12.960 | and someone had brought along a Theragun.

00:04:15.280 | It was the first time I had seen one,

00:04:16.560 | and pretty soon that thing was getting passed along

00:04:18.440 | and became one of the more coveted devices on board.

00:04:21.120 | Everyone wanted time with this thing because it was great.

00:04:23.020 | You could give yourself a really terrific massage

00:04:26.000 | and get deep into the tissue and relieve soreness.

00:04:28.760 | When I got back, I got a Theragun,

00:04:30.440 | and so I'm delighted that they're sponsoring the podcast.

00:04:33.740 | Whether or not you want to treat your muscles

00:04:35.960 | because they're tense from working out

00:04:37.480 | or whether or not you just want to release stress,

00:04:39.060 | it's a terrific tool.

00:04:40.800 | Many of you are familiar probably with professional massages,

00:04:44.020 | but a Theragun is interesting

00:04:45.720 | because you can basically give yourself

00:04:46.920 | a deep tissue massage anytime, anywhere.

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00:04:51.240 | If you want to try Theragun, you can try it for 30 days.

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00:05:01.640 | That's the one that I use or another one of their models.

00:05:03.880 | That's theragun.com/huberman to try Theragun.

00:05:08.600 | This episode marks the beginning of a new topic

00:05:11.440 | for the Huberman Lab Podcast.

00:05:13.800 | As many of you already know,

00:05:15.800 | we go deep into a particular topic over four,

00:05:18.360 | sometimes even five episodes.

00:05:20.380 | We just closed out the episodes on hormones.

00:05:23.280 | Now we are going to talk about

00:05:24.760 | how to optimize physical performance and skill learning.

00:05:28.700 | We're going to look deep at the science behind this

00:05:31.080 | as well as specific practices.

00:05:33.520 | In fact, today, you're going to hear about specific tools

00:05:36.400 | that you can use to improve endurance and strength

00:05:40.000 | by up to, I'm not making this up,

00:05:42.160 | three or four times your current capacity.

00:05:45.200 | This is based on studies that were done at Stanford

00:05:47.720 | and are currently in use

00:05:49.160 | by collegiate and professional teams.

00:05:51.640 | If you're not a professional athlete or a serious athlete,

00:05:55.420 | that's okay.

00:05:56.260 | The topics this month

00:05:57.320 | and all the information we are going to cover

00:05:59.280 | are going to make you a better recreational exerciser

00:06:02.080 | as well.

00:06:03.660 | If you're not an exerciser

00:06:04.920 | and you're thinking about getting into that,

00:06:06.360 | or if you live in the Northern hemisphere

00:06:08.060 | and you're just thinking about the beach this summer,

00:06:10.560 | fat loss, muscle building, that sort of thing,

00:06:13.640 | this month, we're going to cover all of that as well.

00:06:16.360 | There's so much confusion out there

00:06:18.100 | about how to optimize fat loss, muscle building,

00:06:21.180 | improvements in flexibility, for instance,

00:06:23.280 | or skill learning.

00:06:24.400 | I know many of you aren't so focused

00:06:26.080 | on the cosmetic aspects of physical exercise,

00:06:29.200 | but are interested in actual skill learning.

00:06:31.380 | We're going to talk about that too.

00:06:33.120 | I want to just take a moment

00:06:35.700 | to reflect on something that came up last episode.

00:06:38.560 | If you didn't see that episode, that's quite all right.

00:06:41.320 | But last episode,

00:06:42.180 | we were talking about the hormones adrenaline and cortisol

00:06:45.120 | and how to leverage those towards attention and learning.

00:06:48.760 | And there was a little bit of confusion

00:06:50.380 | that I want to clarify.

00:06:51.800 | I mentioned an optimal protocol for learning

00:06:54.340 | that involved leveraging adrenaline,

00:06:56.560 | also called epinephrine.

00:06:58.000 | And it involved four steps.

00:07:00.300 | The four steps that I spelled out

00:07:02.340 | were to be calm and focused

00:07:04.960 | while one is trying to acquire or learn the new skill,

00:07:08.680 | cognitive skill or motor skill.

00:07:10.480 | Then to have a spike in adrenaline,

00:07:13.480 | I mentioned ways to do that,

00:07:15.040 | using cold or breathing or other tools.

00:07:18.020 | Immediately after the learning episode,

00:07:20.700 | then to incorporate what I call non-sleep deep rest,

00:07:24.040 | a 20 minute episode of a shallow nap

00:07:27.800 | or some other protocol like NSDR,

00:07:30.440 | non-sleep deep rest protocol,

00:07:32.160 | of which we always provide links in the captions.

00:07:35.080 | And then to try and optimize sleep later that night

00:07:38.320 | and the subsequent night.

00:07:39.780 | Some of you heard this and it sunk in right away

00:07:43.400 | and it was straightforward.

00:07:44.600 | Others said, wait, I thought from a previous episode,

00:07:47.280 | even before that,

00:07:48.120 | you said you're supposed to do non-sleep deep rest

00:07:49.920 | immediately after learning.

00:07:51.080 | No, we added another step.

00:07:54.440 | The logic still follows

00:07:55.880 | that you want to be calm and focused during learning.

00:07:59.040 | Then you want to spike adrenaline at the end.

00:08:00.960 | Most people get that backward.

00:08:02.320 | They're drinking too much coffee

00:08:03.620 | or even taking nootropics and things,

00:08:05.240 | trying to be really focused while learning.

00:08:07.140 | Some people are taking Adderall recreationally,

00:08:09.660 | something I don't recommend.

00:08:11.040 | That's actually getting the whole process backwards

00:08:13.160 | if you look at the data and the physiology.

00:08:15.040 | You want to spike adrenaline at the end

00:08:17.320 | or immediately after a learning episode

00:08:20.060 | and then non-sleep deep rest and then sleep itself.

00:08:24.400 | Okay, four steps.

00:08:25.420 | Hope that clarifies things for you.

00:08:27.000 | If you have any additional questions,

00:08:28.360 | please put them in the comment section below.

00:08:31.280 | Okay, so let's talk about physical performance.

00:08:34.900 | There are so many variables to physical performance

00:08:37.920 | and we can manage physical performance and skill learning

00:08:41.680 | from a variety of contexts.

00:08:43.840 | I made just a short list of some of the things

00:08:45.600 | that come to mind that can powerfully impact

00:08:47.920 | physical performance and skill learning.

00:08:50.240 | Some of them are what I would consider foundational.

00:08:53.160 | They allow you to show up with your current ability.

00:08:56.720 | And if you were to disrupt those,

00:08:58.720 | you would perform less well.

00:09:00.540 | So things like getting a good night's sleep,

00:09:03.360 | things like being properly hydrated,

00:09:05.960 | things like being well-nourished,

00:09:08.060 | whatever that means to you.

00:09:09.180 | I know some of you like to exercise fasted.

00:09:11.120 | Some of you prefer to have food in your stomach

00:09:14.640 | or have eaten a couple hours before.

00:09:16.540 | There are supplements, there are drugs,

00:09:19.220 | there are different ways to breathe.

00:09:20.740 | There are so many tools related to mindset, visualization.

00:09:24.300 | There are machines and devices.

00:09:25.900 | It's just a vast space, but it's not infinite.

00:09:30.320 | And there are a few things in the list of things

00:09:33.880 | that can impact and even optimize physical performance

00:09:37.440 | and skill learning that have an outsized effect

00:09:41.040 | that any of you can use.

00:09:42.400 | Many of them, most of them are low to zero cost.

00:09:45.840 | So today we are going to focus on what I believe

00:09:48.880 | to be one of the most powerful tools

00:09:52.460 | to improve physical performance

00:09:54.700 | and skill learning and recovery.

00:09:57.520 | We'll talk about why that's important.

00:10:00.400 | And that's temperature.

00:10:02.540 | Now, many of you might think, oh, well, that's kind of boring.

00:10:04.780 | I want to know about the magic pill that I can take

00:10:07.380 | that's going to allow me to dunk a basketball

00:10:09.020 | if I currently can't, or I want to know about the thing

00:10:11.080 | that's going to let me run further and faster,

00:10:12.780 | is going to shed fat.

00:10:14.200 | Believe it or not, temperature is the most powerful variable

00:10:18.840 | for improving physical performance and for recovery.

00:10:23.160 | I would argue it's even more important than sleep

00:10:25.840 | because temperature itself is going to dictate

00:10:28.880 | how well and when you sleep

00:10:30.680 | and the depth of your total recovery.

00:10:32.580 | There are two aspects to temperature, of course.

00:10:36.140 | There's heat and there's cold.

00:10:38.780 | We are mainly going to focus on cold as a way to buffer heat.

00:10:43.780 | In a previous podcast episode,

00:10:45.940 | I talked all about growth hormone.

00:10:47.780 | You can find that episode about thyroid and growth hormone

00:10:50.180 | and how heat can be a powerful stimulus

00:10:52.480 | for increasing growth hormone,

00:10:54.520 | which is involved in tissue repair and et cetera,

00:10:56.860 | can burn fat and improve metabolism in various ways.

00:11:00.720 | However, cold, I would argue,

00:11:03.680 | is even more powerful than heat as a tool.

00:11:06.520 | And I'm not just talking about putting ice packs

00:11:08.600 | on sore muscles or slightly sprained limbs and ankles

00:11:13.360 | and things of that sort.

00:11:14.780 | We're going to talk about cold

00:11:16.180 | from the standpoint of thermal physiology.

00:11:19.840 | This is a literature that's rich in scientific information

00:11:23.680 | that goes back very deep into the last century

00:11:27.680 | where physiologists and neuroscientists figured out

00:11:30.560 | that there are different compartments in your body

00:11:33.320 | that heat and cool you differently

00:11:35.440 | and that you can leverage those in order to double,

00:11:38.600 | and as I mentioned before,

00:11:39.440 | even triple or quadruple your work output,

00:11:41.720 | both strength, repetitions, and endurance.

00:11:44.840 | So this is not weak sauce, as they say.

00:11:47.380 | This is the stuff that can really shift the needle

00:11:50.940 | quite a bit.

00:11:51.780 | And it's not just about performing well once,

00:11:54.660 | it's about being able to perform well

00:11:56.340 | and recover from that performance

00:11:57.900 | so that you do even better

00:11:59.500 | when you're not incorporating these tools

00:12:02.060 | on days where, for instance, you can't access cold

00:12:05.620 | or an ice pack or an ice bath or things of that sort.

00:12:09.240 | So we're going to cover cold.

00:12:10.600 | We're going to talk a little bit about the physiology

00:12:13.120 | of cold and heat and how they work,

00:12:15.300 | because as you've probably heard me say before,

00:12:19.140 | if you can understand some mechanism,

00:12:21.220 | if you can just push yourself

00:12:22.300 | through a little bit of new knowledge

00:12:23.740 | into understanding a little bit of mechanism

00:12:26.460 | about how you work,

00:12:27.660 | you'll be in a far better position to implement the tools

00:12:31.540 | in the best and most flexible ways for your needs.

00:12:34.780 | This is why at the Huberman Lab Podcast,

00:12:37.220 | I never ever do a just list of the things that you should do.

00:12:41.300 | I don't believe in the just tell me what to do.

00:12:43.600 | First, I tell you why you should do something,

00:12:45.840 | what's the logical framework that it's grounded in,

00:12:48.200 | and then we distill that down to specific protocols.

00:12:51.640 | For those of you that are too impatient for that,

00:12:53.300 | there are millions, if not billions,

00:12:55.440 | of other resources out there

00:12:56.560 | that will take you into the cul-de-sac

00:12:58.620 | of one protocol that will work and then stop working

00:13:01.680 | or might work for you indefinitely.

00:13:03.280 | That's not how we work here.

00:13:04.940 | This is about really understanding the mechanism

00:13:07.580 | so that you can tweak things and modify things,

00:13:10.280 | adjust the timing and the dosage of things,

00:13:12.520 | and really get the most out of these tools and protocols.

00:13:16.120 | Everything I'm going to talk about

00:13:18.400 | pertains to both endurance exercise

00:13:21.000 | and strength and speed type exercise.

00:13:24.560 | So sprints, weightlifting, endurance work,

00:13:27.560 | and to some extent flexibility,

00:13:29.100 | but we are going to cover flexibility in depth

00:13:32.040 | as well as another feature that's not often talked about,

00:13:34.360 | which is suppleness or smoothness of movement

00:13:37.280 | over different ranges of movement in a subsequent episode.

00:13:40.920 | Let's start by talking about temperature.

00:13:43.980 | What is temperature?

00:13:45.700 | How does temperature impact the body

00:13:48.380 | and its ability to perform, including learn new skills?

00:13:52.340 | So everyone probably remembers,

00:13:54.540 | or has at least heard of the word homeostasis, right?

00:13:58.260 | That the body wants to remain

00:14:00.080 | in a particular range of temperatures,

00:14:02.720 | that it doesn't like to be too hot or too cold.

00:14:05.640 | And I want to emphasize from the outset

00:14:08.240 | that there are many mechanisms that are installed into us

00:14:12.080 | by way of our evolutionary design and our genome,

00:14:16.280 | meaning we were just born with this stuff ready

00:14:18.660 | to keep our body temperature in a particular narrow range.

00:14:21.740 | Heating up too much is just plain bad.

00:14:26.380 | It's not just bad for physical performance,

00:14:28.240 | it's bad for all tissue health.

00:14:31.660 | If your brain heats up too much,

00:14:32.980 | neurons start dying and those neurons don't come back, okay?

00:14:37.780 | You may have heard about neurogenesis,

00:14:39.460 | the ability for the brain to regenerate itself

00:14:42.040 | or generate new neurons in adulthood.

00:14:43.620 | There's very little neurogenesis, excuse me, in adulthood,

00:14:48.380 | even any time after puberty, really.

00:14:50.880 | And you don't want to lose neurons

00:14:53.580 | in the central nervous system.

00:14:54.900 | If you get too hot, that'll happen.

00:14:56.660 | It's called hyperthermia.

00:14:58.240 | You want to avoid hyperthermia.

00:14:59.660 | And you have many mechanisms that are built into you

00:15:02.980 | to avoid becoming hyperthermic.

00:15:05.820 | The other thing that happens when we get too warm

00:15:08.560 | is that we have in all of our cells

00:15:11.780 | what are called enzymes.

00:15:14.100 | You generally know if something's an enzyme

00:15:16.580 | because it ends in the letters A-S-E, right?

00:15:19.920 | So lipase is an enzyme that exists to digest fats.

00:15:24.920 | You have proteases that are there to digest proteins, right?

00:15:29.920 | So anytime you see A-S-E, chances are it's an enzyme.

00:15:34.920 | Enzymes are proteins and they have a particular structure

00:15:41.100 | and their structure becomes modified when heat increases.

00:15:46.100 | And that's not good.

00:15:47.460 | You want their structure to be of a particular type.

00:15:50.340 | Imagine a car with four wheels.

00:15:52.580 | Let's just say the car is the enzyme.

00:15:55.020 | If it gets too hot, it's like two of the wheels fall off

00:15:58.460 | and that thing can't function.

00:15:59.860 | So one of the reasons why the body and nature

00:16:02.980 | goes through so much effort to build in mechanisms

00:16:05.780 | to make sure that we don't become too warm

00:16:07.940 | is because when we get too warm, these enzymes don't function

00:16:11.860 | cells stop functioning.

00:16:13.460 | They stop being able to generate energy.

00:16:15.720 | They stop being able to digest things.

00:16:18.380 | You stop being able to think

00:16:20.260 | and eventually those cells start dying off entirely.

00:16:24.460 | So keeping temperature in a particular range is really good.

00:16:27.600 | You don't want to get too hot.

00:16:29.460 | We have much more flexibility in terms of getting cold.

00:16:32.780 | Now you don't want to become hypothermic either.

00:16:35.060 | You can die from hypothermia

00:16:36.460 | just like you can die from hyperthermia.

00:16:39.140 | However, that you have a lot more range to be cold

00:16:44.140 | than you do to be too warm, okay?

00:16:46.780 | And in general, the idea is to keep the body and brain

00:16:50.620 | in a particular range, but anytime we do anything,

00:16:53.900 | our body temperature can shift.

00:16:56.840 | So for instance, if you were to stand next to a campfire

00:17:01.000 | or you were outside on a hot day,

00:17:03.060 | various things would happen to dump heat from your body.

00:17:06.960 | If you were outside on a cold day

00:17:08.580 | or you were to get into a cold shower or a cold lake,

00:17:11.720 | various things would happen

00:17:12.820 | to insulate heat within your body.

00:17:14.380 | This is all pretty straightforward and obvious I realize.

00:17:17.020 | Now, what are those things?

00:17:18.620 | Well, there are a huge category of them.

00:17:21.180 | When you get into cold water, you secrete adrenaline.

00:17:23.980 | On a hot day, if it's really hot or in a very hot sauna

00:17:27.200 | or in the hot desert, you will generate

00:17:28.700 | what are called heat shock proteins

00:17:30.460 | which will set off other sets of cascades,

00:17:33.520 | metabolic cascades, biological cascades.

00:17:36.240 | But the simplest way to think about this process

00:17:40.380 | is that when we get cold, we tend to vasoconstrict.

00:17:45.300 | Our blood vessels tend to constrict

00:17:47.640 | and we tend to push energy toward the core of our body

00:17:51.120 | to preserve our core organs, okay?

00:17:53.280 | So our periphery, our hands and our feet and our toes

00:17:56.100 | and our legs become colder and our core therefore

00:17:59.620 | can maintain blood to that area

00:18:01.620 | and we are insulating our core.

00:18:03.540 | Conversely, when we heat up, our blood vessels vasodilate.

00:18:08.760 | They expand a bit and more blood flows to our periphery

00:18:13.020 | and more blood can move throughout the body generally

00:18:16.220 | and we will perspire, we will sweat.

00:18:19.560 | Water will actually get pulled out of the blood

00:18:22.020 | to some extent, moved up through sweat glands

00:18:24.620 | and will be brought to the skin surface

00:18:27.180 | so that it can be dumped.

00:18:28.780 | We are dumping heat.

00:18:30.820 | Animals, as you know, vary in their capacity to sweat.

00:18:34.600 | Some animals like camels won't start sweating at first.

00:18:38.340 | If they heat up, what they'll do is they'll spit.

00:18:40.540 | They'll dump heat by spitting, okay?

00:18:43.220 | Dogs pant, Costello is off to my left here.

00:18:46.300 | He pants when he gets too warm, he can't sweat

00:18:49.860 | or dogs can maybe sweat a little bit.

00:18:52.680 | But we can sweat and you've probably noticed

00:18:56.660 | that on a humid hot day, you'll feel much warmer

00:19:01.320 | just walking or running than you would

00:19:03.800 | with the equivalent exercise or movement

00:19:06.560 | that you would on a cold day.

00:19:08.060 | And some of you probably know this, but if you don't,

00:19:10.360 | the reason is you sweat on a cold day,

00:19:13.300 | but because the air is dry typically,

00:19:16.660 | you will bring that sweat to the surface

00:19:19.780 | and provided you're wearing clothes

00:19:21.780 | that allow some air to get out away from the body.

00:19:26.700 | So you're not wearing really tight spandex type clothing

00:19:29.500 | or something like that,

00:19:30.340 | or seal type saran wrap type clothing,

00:19:32.800 | that sweat will evaporate off into the dry atmosphere.

00:19:37.420 | Whereas on a humid day, the reason you see people

00:19:40.140 | in New York and Florida on a humid summer day

00:19:42.660 | and they're like moving their shirts off themselves

00:19:44.380 | and you see people with big sweat stains

00:19:46.100 | and back sweat stains and all this kind of stuff

00:19:49.300 | is because they're sweating as they normally would,

00:19:52.460 | but it's humid and so the humidity of the air

00:19:55.900 | doesn't allow transfer of that sweat

00:19:58.000 | into the atmosphere as readily and so you're hot, okay?

00:20:02.640 | So without the evaporation, you're going to be warmer.

00:20:06.460 | So we evaporate off sweat, we sweat,

00:20:09.400 | and we vasodilate when we want to dump heat.

00:20:11.700 | When we want to maintain heat,

00:20:13.260 | we vasoconstrict and we tend to not sweat.

00:20:16.600 | The other thing that happens is you'll get goosebumps,

00:20:19.480 | so-called goose pimples, they're sometimes called.

00:20:21.960 | Those are a throwback to the time where we had fur

00:20:25.820 | over most, not all of our body.

00:20:27.760 | All mammals in the cold have a process whereby adrenaline

00:20:32.760 | is released at low levels, typically, into the body.

00:20:36.560 | That adrenaline activates what are called sympathetic fibers.

00:20:40.600 | They have nothing to do with sympathy.

00:20:42.280 | Those little fibers, which are neurons,

00:20:44.380 | those fibers that, what I'm saying are fibers are neurons,

00:20:46.820 | not clothing fibers, reach up into the skin.

00:20:49.420 | So your whole body is covered with these little tiny neurons

00:20:51.940 | that reach up into the skin and when we are cold,

00:20:54.780 | they actually mechanically take the hair follicle

00:20:57.860 | and bend it up.

00:21:00.140 | It's a process called piloerection, P-I-L-O, erection, okay?

00:21:05.140 | So on a hot day, you want to dump heat, okay?

00:21:09.520 | So on a hot day, what would happen is

00:21:11.920 | you'd actually not see those goose pimples

00:21:14.440 | because you want the hairs lying down,

00:21:16.460 | which actually you would think that might insulate you more,

00:21:18.820 | but would actually let more heat dissipate

00:21:20.780 | out through the skin.

00:21:22.340 | On a cold day, you get these goose pimples or goosebumps,

00:21:25.620 | which are really just an ancient carry over

00:21:27.860 | from the body's attempt to make hair stand up on end.

00:21:32.020 | And when hair step stand up on end

00:21:34.180 | and they're very close together,

00:21:35.140 | that traps air in between them

00:21:36.900 | and actually creates a sort of insulated blanket of warm air.

00:21:40.540 | If you've ever seen an animal like a malamute or a husky,

00:21:45.540 | you might think, oh, that poor thing on a hot day,

00:21:48.280 | what does it do with all that hair?

00:21:50.100 | Well, it can be warm, so the animal will typically pant

00:21:52.900 | and its hair will lay down,

00:21:54.780 | which you might think would act as more of a blanket,

00:21:56.980 | but on a cold day, what'll happen is

00:21:59.160 | they'll become very puffy.

00:22:01.800 | Their hair will stand up on end

00:22:03.280 | and that's actually trapping heat between the hairs

00:22:05.620 | and they're actually quite well insulated.

00:22:07.640 | So it's very important that if you want to understand

00:22:11.260 | how you can leverage temperature for physical performance,

00:22:15.520 | you have to understand that you have vasoconstriction

00:22:18.160 | to conserve heat, vasodilation to dump heat,

00:22:20.540 | that you have sweating to dump heat

00:22:22.200 | and you have conservation of fluids

00:22:24.680 | in order to preserve heat.

00:22:26.480 | That's the most important thing

00:22:29.480 | in terms of understanding the mechanisms

00:22:31.460 | of maintaining and dumping heat.

00:22:33.360 | And now the most important thing to understand is that

00:22:36.440 | if you get too hot,

00:22:37.980 | not only do those enzymes stop working,

00:22:40.480 | but your ability to contract your muscles stops, okay?

00:22:45.200 | I'm going to repeat this because it's vitally important.

00:22:47.960 | ATP is involved in the process

00:22:52.560 | of generating muscle contractions.

00:22:54.280 | Doesn't matter if you're running a marathon,

00:22:55.920 | doesn't matter if you're doing a yoga class,

00:22:57.480 | doesn't matter if you're going for a 700 pound squat.

00:23:01.200 | The range of temperatures within which ATP can function

00:23:04.940 | and muscles can contract is very narrow.

00:23:07.880 | Somewhere around 39 or 40 degrees Celsius,

00:23:11.600 | it drops off and you will not be able

00:23:13.760 | to generate more contractions.

00:23:16.260 | Now that's pretty hot,

00:23:17.300 | but that temperature can be generated locally really fast.

00:23:21.080 | Now, if you're too cold, it's true,

00:23:22.960 | it's hard to generate muscle contractions.

00:23:24.600 | I got into doing some cold water swimming a little while ago

00:23:28.400 | and we would joke that you come out of the water,

00:23:30.460 | we do no wetsuits.

00:23:32.200 | I'm not recommending people do this necessarily

00:23:34.040 | unless you're certainly with somebody else

00:23:35.620 | who's skilled at doing it, which I was.

00:23:37.740 | And you come out and you feel like you have claws for hands.

00:23:40.240 | You could never text on a phone for the first few minutes.

00:23:43.220 | I mean, the water was very, very cold

00:23:45.180 | and you can't even move your face.

00:23:46.660 | And so muscles will become rigid,

00:23:48.800 | but heating up muscles causes them to fail

00:23:52.460 | to be able to generate more contractions.

00:23:55.360 | Put simply, if you get too hot, you stop exercising.

00:23:59.360 | You may not even realize it,

00:24:00.720 | but your will to exercise further,

00:24:03.360 | your ability to push harder

00:24:05.880 | is entirely dependent on the heat of the muscle,

00:24:08.860 | both locally and your whole system.

00:24:11.740 | So let's talk about your whole system

00:24:14.300 | because I just described heat dumping and heat maintaining.

00:24:18.080 | I told you that increasing heat

00:24:20.680 | makes it hard for muscles to contract.

00:24:22.720 | It will stop you from being able to run further and faster.

00:24:26.600 | It will stop you from being able to lift more weights,

00:24:29.440 | more sets, more repetitions.

00:24:31.500 | If you can keep temperature in range, however,

00:24:34.760 | in a proper range, you will be able to do more work.

00:24:38.800 | You will be able to create greater output.

00:24:41.540 | You'll be able to lift more weight, more sets, more reps,

00:24:45.140 | and you'll be able to run further.

00:24:47.540 | Now, there are data that I'm going to talk about

00:24:49.440 | in a little bit that are absolutely striking

00:24:51.880 | that underscore that statement.

00:24:53.160 | There are data from my colleague, Craig Heller's lab

00:24:55.200 | in the Department of Biology at Stanford.

00:24:57.280 | And there are data that are now being implemented.

00:24:59.840 | They were first implemented in a grant funded by DARPA,

00:25:03.140 | but now in professional sports teams.

00:25:05.100 | Many, if not all the NFL teams

00:25:07.540 | are now using this technology as well as military uses it.

00:25:10.700 | And not just for sports performance,

00:25:12.520 | but also firefighters, construction workers,

00:25:15.360 | other professions where elevated heat

00:25:18.680 | becomes a barrier to performance.

00:25:20.620 | And you can leverage this to really improve your workouts.

00:25:23.880 | And when I say really improve, it is striking.

00:25:26.020 | I'm going to give away a little hint of this now,

00:25:27.600 | and then I'm going to tell you

00:25:28.440 | a little bit more of the data later

00:25:29.720 | after I tell you the protocols.

00:25:31.320 | Proper cooling of the body,

00:25:35.660 | which has to be done in a very specific way,

00:25:38.500 | has allowed recreational athletes or college students

00:25:42.040 | and typical adults, as well as professional athletes

00:25:45.100 | to go from doing their usual output.

00:25:48.260 | In this case, what comes to mind best

00:25:50.360 | would be a particular professional athlete,

00:25:52.680 | he's a member of the 49ers at the time,

00:25:55.080 | was able to do 40 dips on his first set, 30, 20, 20,

00:25:58.600 | basically did 10 sets of dips unassisted with anything else.

00:26:01.820 | That's an impressive,

00:26:04.160 | especially since he's a really large guy.

00:26:06.880 | 40 dips is respectable.

00:26:08.420 | These are strict full range dips.

00:26:10.680 | And then by the 10 set, there's a steep drop-off.

00:26:14.120 | Using proper cooling of particular body compartments,

00:26:18.640 | he was able to triple that within less than a week

00:26:23.260 | and maintain that performance

00:26:25.320 | even without the cooling approach.

00:26:26.780 | So it was actually a conditioning effect, all right?

00:26:29.860 | I'll get back to this in a little bit,

00:26:31.400 | but there are other fantastic leaps of effort

00:26:35.360 | and leaps of performance that were demonstrated,

00:26:38.800 | including endurance running.

00:26:40.580 | Before I continue any further,

00:26:43.360 | I just want to underscore again that overheating is terrible.

00:26:47.000 | There's a famous example of this.

00:26:50.460 | This was about 10, 15 years ago

00:26:52.460 | when a number of dietary supplements

00:26:54.620 | that included things like epinephrine, which is a stimulant,

00:26:57.740 | it's a beta adrenergic stimulant,

00:27:00.800 | drugs like clambuterol,

00:27:02.320 | which were then banned from the Olympics,

00:27:04.340 | which are still out there a bit in recreational use,

00:27:06.400 | which were beta adrenergic agonists.

00:27:08.880 | So these are drugs that sort of mimic

00:27:11.760 | epinephrine adrenaline to some extent.

00:27:13.780 | I know I'm oversimplifying this here.

00:27:15.360 | They improve fat loss because of the effects on metabolism,

00:27:18.560 | but they heat up the body.

00:27:20.180 | And what happened was this hit the press very widely

00:27:22.680 | is high school football players

00:27:24.720 | and various professional athletes were dropping dead

00:27:26.840 | because they were overheating

00:27:27.800 | during practice or in competition.

00:27:29.840 | So much so that clambuterol was banned,

00:27:32.720 | although every once in a while,

00:27:33.640 | somebody gets in trouble for using this.

00:27:36.680 | There was an instance of this recently

00:27:38.020 | in professional boxing,

00:27:39.040 | which was attributed to a bad meat

00:27:41.160 | that contained the clambuterol.

00:27:42.840 | I don't know what the source was.

00:27:44.480 | I don't have any commentary about that,

00:27:47.580 | but it still is in use,

00:27:48.840 | but these drugs increase body temperature,

00:27:51.740 | increase fat loss, but carry a severe danger.

00:27:55.940 | And that's the danger of hyperthermia.

00:27:58.560 | In fact, I would argue,

00:27:59.680 | and I think in talking to some folks

00:28:01.760 | at various professional fighting organizations,

00:28:03.940 | it's very clear that a lot of the deaths

00:28:05.660 | that one sees in professional combat sports

00:28:07.960 | may have to do as much with dehydration and overheating

00:28:13.040 | as it does with getting hit in the head,

00:28:15.360 | which is also bad, but that things can compound.

00:28:17.800 | They can have a synergistic effect.

00:28:19.920 | And just a note about that

00:28:21.800 | and hyperthermia and its dangers as well.

00:28:24.480 | My first project ever in science

00:28:26.240 | was to evaluate the thermogenic effects of MDMA, of ecstasy.

00:28:30.260 | That was my senior thesis in college, actually.

00:28:33.640 | And so what we found was that indeed,

00:28:37.080 | drugs that remove your understanding of how warm you are

00:28:41.920 | cause you to not take on the appropriate behaviors

00:28:45.560 | to cool yourself, right?

00:28:47.240 | So your vasoconstriction and your sweating,

00:28:50.680 | those are autonomic.

00:28:51.840 | Those are going to happen no matter what,

00:28:53.280 | unless you happen to take something that blocks that effect.

00:28:56.420 | However, there are a lot of things that we as humans do

00:28:59.140 | to prevent ourselves from overheating.

00:29:01.080 | And the main one is stop.

00:29:04.080 | When we are running in the desert

00:29:05.960 | or when we're running very hard and suddenly we stop,

00:29:09.180 | oftentimes that's because the muscles are overheating.

00:29:12.040 | It's a subconscious thing.

00:29:13.440 | We won't often think, oh, I'm really much too warm.

00:29:15.920 | It's just that we stop

00:29:17.600 | and it's a self-preservation mechanisms.

00:29:19.760 | Sometimes it kicks in too early.

00:29:21.120 | Sometimes it kicks in too late.

00:29:23.320 | Kicks in too late, you can die.

00:29:25.400 | There's an instance in the 1984 Olympics

00:29:27.380 | where that was the first year, I believe,

00:29:30.100 | that there was a women's marathon.

00:29:32.360 | I think that's correct.

00:29:33.560 | And one of the front runners or top picks for winning

00:29:36.980 | was heading into the stadium.

00:29:38.480 | And all of a sudden it seemed as if she was lost.

00:29:41.240 | She was kind of wandering around

00:29:42.600 | not knowing where she should go.

00:29:44.120 | And in fact, she was in a position to win

00:29:46.160 | or at least take second place, at least take silver,

00:29:48.720 | got totally disoriented and did miserably in the race.

00:29:52.040 | And she was hyperthermic.

00:29:53.720 | She was running against that reflex to stop.

00:29:56.680 | So dumping heat is key.

00:29:58.600 | So how do you dump heat in order to perform longer safely?

00:30:03.600 | Well, in order to understand that,

00:30:06.280 | you have to understand that the body

00:30:07.840 | has three main compartments for regulating temperature.

00:30:11.620 | We don't just have a center and a periphery.

00:30:13.680 | We have three main compartments.

00:30:15.360 | And there's one compartment in particular

00:30:17.600 | that all of you or most all of you, I have to assume, have.

00:30:22.400 | And if you can understand how that works,

00:30:25.360 | you can do tremendous things for your performance

00:30:27.880 | and for your recovery.

00:30:29.600 | So what I'm about to tell you will allow you

00:30:31.660 | to perform better in all forms of exercise.

00:30:34.740 | And it is not commonly known, unfortunately.

00:30:37.520 | I'm here to try and change that.

00:30:39.740 | You have three compartments for increasing

00:30:43.000 | or dumping heat in your body.

00:30:44.960 | One is your core, we already talked about that,

00:30:48.160 | your core organs, your heart, your lungs,

00:30:49.860 | your pancreas, your liver, the core of your body.

00:30:54.000 | The other is your periphery, which are obviously your arms

00:30:58.080 | and your legs and your feet and your hands.

00:31:00.260 | But then there's a third component,

00:31:02.780 | which is there are three locations on your body

00:31:06.080 | that are far better at passing heat out of the body

00:31:09.900 | and bringing cool into the body such that you can heat up

00:31:14.900 | or cool your body everywhere very quickly.

00:31:19.260 | Those three areas are your face, the palms of your hands

00:31:24.260 | and the bottoms of your feet.

00:31:26.680 | Now the skin on your hands and on the bottoms of your feet

00:31:29.780 | and to some extent on your face are called glaborous skin.

00:31:33.300 | That's G-L-A-B-O-R-O-U-S, glaborous skin.

00:31:39.040 | And what's special about those areas of your body

00:31:42.320 | and the glaborous skin is that the arrangement of vasculature

00:31:47.320 | of blood vessels, capillaries and arteries

00:31:50.720 | that serve those regions is very different

00:31:53.380 | than it is elsewhere in your body.

00:31:55.840 | Now this has ancient roots.

00:31:59.340 | Typically, if you were another mammal,

00:32:01.720 | like a bear or some sort of ape,

00:32:04.720 | you would have hair all over your body.

00:32:06.920 | Now we all know some pretty hairy people

00:32:08.720 | or presumably you've heard that there are these hairy people.

00:32:11.060 | I know a few excessively hairy people

00:32:14.240 | and Costello is excessively hairy

00:32:15.720 | but he's not a person obviously.

00:32:17.900 | But all mammals have hair on their bodies.

00:32:21.800 | Just some people have very light hair or very fine hair.

00:32:25.240 | We don't have hair on these glaborous skin regions.

00:32:29.860 | Now, of course you can have beard or facial hair growth

00:32:33.040 | but there are still regions like the cheeks

00:32:35.160 | and other areas that maintain this special vasculature.

00:32:38.720 | So technically the hands and feet are real glabrous skin

00:32:41.860 | and the face is not always quite classified as glabrous

00:32:45.820 | but these three locations, palms of hands, not tops

00:32:49.800 | and bottoms of feet are very good at dumping heat

00:32:54.360 | and bringing in cool.

00:32:56.360 | And the reason is there's a rule in vascular biology

00:33:01.300 | that blood moves from arteries to capillaries

00:33:04.880 | and then to veins and then back to the heart, okay?

00:33:07.960 | So arteries, which are the big ones obviously,

00:33:11.000 | capillaries, which are the little fine ones

00:33:13.120 | where oxygen and carbon dioxide are exchanged

00:33:16.400 | and veins, which then bring blood back to the heart

00:33:20.880 | and other tissues of course.

00:33:22.380 | In these three regions of your hands, your face

00:33:27.920 | and the bottoms of your feet,

00:33:29.760 | we have what are called AVAs.

00:33:32.040 | AVAs are a very special pattern of vasculature.

00:33:36.400 | AVAs are described in the medical textbooks.

00:33:38.920 | You can find them in Grey's Anatomy, not the television show

00:33:41.720 | but the actual Grey's Anatomy textbook

00:33:44.240 | which is a real thing that exists

00:33:46.160 | and in all medical textbooks, okay?

00:33:49.620 | So let's talk about AVAs and what they are

00:33:52.400 | and why they allow these three regions of the body

00:33:54.980 | to heat or cool ourselves more readily.

00:33:58.300 | So what are AVAs?

00:34:01.760 | AVAs are arteriovenous osteomoses.

00:34:05.560 | So if you want to look that up, you can just look up AVAs,

00:34:08.920 | veins, capillaries, arteries, if you like

00:34:11.880 | but I'll spell it for you.

00:34:13.520 | A-R-T-E-R-I-O, arteriovenous, V-E-N-O-U-S,

00:34:19.840 | arteriovenous anastomoses, A-N-A-S-T-O-M-O-S-E-S.

00:34:30.080 | Arteriovenous anastomoses, okay?

00:34:32.520 | You want to know about arteriovenous anastomoses, trust me.

00:34:36.640 | And you want to remember that they are in your hands,

00:34:39.120 | the bottoms of your feet and on your face

00:34:41.340 | and in particular on the palms of your hands,

00:34:43.340 | not the tops of your hands.

00:34:44.720 | Now, before I said blood flows typically

00:34:47.760 | from arteries to capillaries to veins

00:34:49.820 | and then back to the heart

00:34:51.400 | but AVAs are direct connections

00:34:53.620 | between the small arteries and the small veins.

00:34:56.620 | They bypass the capillaries to some extent.

00:35:00.040 | They're little short vessel segments.

00:35:02.360 | They have a big large inner diameter

00:35:05.240 | and they have this very thick muscular wall

00:35:08.260 | and they get input from what are called adrenergic neurons.

00:35:12.200 | They get input from neurons

00:35:13.820 | that release norepinephrine and epinephrine

00:35:17.320 | which allows them to contract or dilate.

00:35:20.040 | Now, there's some rules of physics

00:35:21.400 | that talk about how the radius of a pipe

00:35:24.500 | and small changes in the radius of a pipe

00:35:27.320 | leads to massive increases in the rate

00:35:31.140 | and amount of stuff that can flow through that pipe, okay?

00:35:35.280 | That's a rule of physics that says essentially

00:35:37.220 | that the radius is proportional

00:35:40.200 | to the amount of stuff that can flow through something

00:35:43.080 | to the fourth power.

00:35:44.420 | We're not going to make this a physics class

00:35:45.920 | but if you want to look that up, you can.

00:35:47.960 | You can just look up how does the radius of a tube or pipe

00:35:50.820 | relate to how quickly or how much it can,

00:35:53.400 | stuff can flow through it.

00:35:54.840 | What you need to know,

00:35:56.340 | even if you don't want to know any of the underlying physics

00:35:58.200 | is that these AVAs allow more heat

00:36:01.100 | to leave the body more quickly

00:36:03.940 | and more cool to enter the body more quickly

00:36:07.340 | than other venous arterial capillary beds

00:36:12.340 | throughout the body.

00:36:13.720 | In other words, you can heat up best at the face,

00:36:16.840 | the palms and the bottoms of the feet

00:36:18.820 | and you can cool down best at the face, the palms

00:36:22.740 | and the bottoms of the feet

00:36:23.620 | than you can anywhere else on your body.

00:36:25.660 | When I say heat up or cool down,

00:36:27.120 | I mean actually heat or cool the core and your brain, okay?

00:36:31.760 | So this is vitally important.

00:36:33.180 | I realize we're getting down into the mechanistic weeds here

00:36:35.600 | but you need to know that these three compartments

00:36:38.360 | of your body, palms, bottoms of feet and face

00:36:41.700 | are your best leverage points for manipulating temperature

00:36:46.120 | to vastly improve physical performance, okay?

00:36:50.280 | I also want to point out

00:36:52.080 | that the work that I'm going to tell you about

00:36:54.280 | is not work from my laboratory.

00:36:55.920 | It's the work of, as I mentioned,

00:36:57.440 | my colleague Craig Heller's laboratory at Stanford

00:37:00.180 | and we're going to have Craig on as a guest

00:37:02.360 | to talk more about these discoveries.

00:37:04.660 | They are his and his colleagues discoveries

00:37:07.240 | and how you can leverage them.

00:37:09.700 | They're building out some amazing technology.

00:37:12.340 | I had a conversation with Craig yesterday

00:37:14.500 | as a prelude to this episode

00:37:17.080 | and to the future conversation with him.

00:37:19.240 | So you're getting the very latest on this topic.

00:37:22.720 | So what Craig and his colleagues did

00:37:24.680 | really illustrates perfectly

00:37:26.560 | what these body surfaces can do and why.

00:37:29.560 | They were studying overheating in athletes

00:37:35.080 | and in military and in construction workers

00:37:38.160 | and trying to prevent it.

00:37:39.980 | And they did a bunch of experiments.

00:37:41.660 | I won't go into all of them now

00:37:43.320 | but what they essentially found

00:37:44.520 | was that cooling the palms, palmer cooling

00:37:49.080 | allowed people, athletes and recreational athletes

00:37:54.080 | to run much further, to lift more weight

00:37:57.620 | and to do more sets and reps

00:37:59.680 | to a absolutely staggering degree.

00:38:02.780 | Let's talk for a second a bit more about why we stop,

00:38:09.160 | why we shut off effort when we get too hot.

00:38:13.620 | Because in doing so, you'll really understand

00:38:16.280 | how and why the best protocols exist

00:38:18.920 | for being able to do more work,

00:38:21.040 | to be able to exercise longer

00:38:23.760 | and actually to feel good doing it.

00:38:25.400 | You actually can make a doubling of your dips

00:38:28.080 | or believe it or not a tripling or quadrupling

00:38:30.320 | or more of your pull-ups fairly straightforward.

00:38:33.560 | I mentioned before that when muscle heats up,

00:38:38.000 | enzymes start getting disrupted

00:38:41.880 | and ATP and muscles can't work so well

00:38:44.840 | and those muscles can't contract.

00:38:46.640 | Let's get a little more specific about that.

00:38:48.440 | The enzyme that's involved here

00:38:50.480 | is something called pyruvate kinase.

00:38:52.680 | You don't need to know about pyruvate kinase

00:38:54.360 | but what you do need to know is that it ends ASE

00:38:56.660 | which means it's an enzyme

00:38:58.840 | and pyruvate kinase is essentially a rate limiting step.

00:39:03.840 | It's a critical step that you can't bypass

00:39:07.120 | if you want muscles to contract

00:39:08.480 | and it's very temperature sensitive.

00:39:10.440 | Therefore, if you can keep temperature lower,

00:39:16.280 | you can do more work per unit time.

00:39:19.100 | You can do more pull-ups

00:39:20.760 | and that actually was done by Craig and his colleagues.

00:39:23.960 | Excuse me, the pull-ups weren't actually done by Craig.

00:39:26.000 | I don't know how many pull-ups Craig can do.

00:39:27.360 | I'll ask him next time, both cooled and uncooled

00:39:29.960 | how many pull-ups he can do.

00:39:31.640 | But what they essentially did

00:39:33.280 | is they brought someone into their laboratory

00:39:36.040 | who could do 10 pull-ups on the first set

00:39:39.380 | and they were able to get 10 rest two or three minutes,

00:39:42.260 | get another 10 rest two or three minutes

00:39:44.080 | and if you've ever tried this,

00:39:45.000 | what you find is that you start dropping

00:39:46.420 | to eight, seven, six, et cetera.

00:39:49.320 | Now, the person might not necessarily feel

00:39:51.880 | like they're overheating, but the muscle is heating up.

00:39:55.340 | Then with their knowledge that these AVAs,

00:39:59.240 | that these portals in the palms

00:40:02.960 | are a great way to both heat the body

00:40:05.880 | but also to dump heat from the body,

00:40:08.360 | they used a device

00:40:10.080 | and I'll talk about what you can do at home

00:40:12.120 | but a device where they had people hold on

00:40:14.600 | to what was essentially a cold tube.

00:40:18.400 | Now, this is crucial.

00:40:20.340 | The tube can't be so cold that it causes vasoconstriction

00:40:24.360 | because then the cold won't pass from the tube

00:40:27.280 | to the hand and to the core.

00:40:29.080 | But if it's the right temperature,

00:40:32.160 | it's neither too hot nor too cold,

00:40:34.800 | that cool from the cold tube passes into the hand,

00:40:39.800 | these so-called palmar regions and then cools the core

00:40:44.360 | and in theory, by lowering body temperature

00:40:47.040 | would allow the person or the athlete to do more work

00:40:50.320 | and indeed that's what they saw.

00:40:51.920 | The actual data, the specific data showed

00:40:55.760 | that subjects could do,

00:40:57.200 | at least the subjects they worked with

00:40:58.640 | on their first day with no cooling,

00:41:00.900 | about a hundred pull-ups

00:41:02.280 | across the timeframe that they had, okay?

00:41:06.600 | So it might've taken anywhere from 10 to 15

00:41:10.000 | or maybe more sets depending on how skilled that person was

00:41:13.120 | but in a fixed amount of time.

00:41:14.880 | Then they came back and did the cooling.

00:41:18.280 | They did it the very next day

00:41:19.640 | which if you've ever trained a muscle the very next day,

00:41:22.840 | typically you wouldn't do as well in its training

00:41:25.960 | if it took any damage from the previous session

00:41:27.920 | or you at least do as well

00:41:29.080 | but you probably wouldn't do what they then observed

00:41:32.160 | which was they started cooling after every other set.

00:41:34.720 | The person would just hold the cold tube,

00:41:37.160 | cool down the body after every other set,

00:41:39.680 | rest, everything else was kept the same

00:41:42.080 | and they found that they went to 180 pull-ups

00:41:45.540 | which is incredible, it's a near doubling.

00:41:48.080 | And by doing this repeatedly over several sessions,

00:41:50.960 | over several weeks, they quickly went in the cooling group

00:41:55.040 | from a maximum of somewhere between 180 and 200

00:41:58.240 | as I recall I'm sort of estimating now

00:42:00.200 | to 600 pull-ups in the equivalent amount of time

00:42:03.560 | which is absolutely incredible.

00:42:06.080 | They then repeated this in a study on the bench press

00:42:09.520 | and actually the bench press study was pretty interesting

00:42:11.680 | because they actually had a control group

00:42:13.620 | that was admittedly taking specific amounts

00:42:16.920 | of anabolic steroids.

00:42:17.960 | The anabolic steroid was testosterone sipinate

00:42:20.600 | which is essentially testosterone

00:42:23.400 | and indeed the testosterone sipinate,

00:42:25.400 | the steroid group improved at a rate of about 1% per week.

00:42:30.240 | In other words, there were differences

00:42:32.840 | and the cooling group basically left all other groups

00:42:36.780 | in the dust, it was just remarkable.

00:42:38.680 | So cooling the core, I want to be very clear

00:42:41.580 | that it's not cooling the muscle,

00:42:42.880 | it wasn't about cooling the chest alone

00:42:44.720 | or just cooling the palms.

00:42:46.360 | It was about allowing cold to pass through the palms

00:42:49.700 | because of the unique vasculature that's there,

00:42:52.920 | these AVAs allowed these subjects

00:42:55.880 | to do far more work per unit time.

00:42:58.600 | And the important thing is that if they were to come back

00:43:02.620 | after doing 600 pull-ups or 500 pull-ups,

00:43:05.700 | you might say, well, wow, that's going to create a situation

00:43:08.400 | where recovery is going to be absolutely impossible.

00:43:11.600 | They could come back, not use the cooling

00:43:13.660 | and they still saw a highly significant increase

00:43:16.180 | in the amount or the number of pull-ups or dips

00:43:19.040 | or bench press weight that they could do, okay?

00:43:21.840 | So what that meant is that it was both

00:43:23.280 | an excellent performance and an excellent training stimulus

00:43:27.120 | that they were able to recover from, okay?

00:43:29.820 | I don't know if all of you are following this

00:43:31.380 | but these are the sorts of increases in exercise output

00:43:35.280 | that are absolutely staggering

00:43:37.120 | and that's why professional teams and the military

00:43:39.900 | and others capitalized on them very quickly and use these,

00:43:44.300 | okay?

00:43:45.140 | Now you may be asking, what about endurance, right?

00:43:49.680 | Not everyone wants to be able to bench press a lot

00:43:52.440 | for multiple reps and sets.

00:43:54.060 | And I should just mention for the bench pressing,

00:43:56.880 | it was, I believe they found people

00:43:58.680 | that could bench press 225, so that's two 45-pound plates

00:44:01.820 | on the 45-pound standard Olympic bar

00:44:03.960 | for repetitions of anywhere from six to 10

00:44:05.880 | and then they had them do the same thing.

00:44:07.080 | They did a set, they'd rest two or three minutes,

00:44:09.360 | sometimes up to four minutes, then do another set,

00:44:11.360 | repeat, repeat, repeat, and with cooling,

00:44:13.560 | they were able to increase the amount of work,

00:44:16.400 | the number of reps with the same weight,

00:44:19.080 | sometimes they did have to increase sets

00:44:21.340 | to approximately double, so it was pretty fantastic.

00:44:25.240 | So with endurance, similar increases have been shown

00:44:29.880 | and the way that they would do those tests

00:44:32.280 | are a little bit different and they also point

00:44:34.160 | to a really important mechanism of why we stop doing work

00:44:38.040 | at all when we perceive

00:44:40.780 | that we are putting in too much effort.

00:44:42.280 | So it gets right to the heart of the relationship

00:44:44.440 | between temperature in muscle and your willpower.

00:44:47.920 | Those are directly related.

00:44:49.320 | Your body heat and your willpower

00:44:51.880 | are linked in a physiological way.

00:44:54.000 | So I'm not talking about the kind of stuff

00:44:55.280 | that you see as kind of like clickbait on the internet

00:44:57.180 | or like increase willpower now or become resilient now

00:45:00.720 | or never do this again if you want to be mentally strong.

00:45:03.020 | I'm talking about a physiological mechanism

00:45:05.540 | that exists in the body and brain that causes you to stop

00:45:09.000 | or that will allow you to continue to go harder and further

00:45:12.860 | than you normally would.

00:45:14.380 | Okay, so let's talk about willpower and heat

00:45:16.780 | and how heat shuts you down.

00:45:19.220 | In other words, if you are cool,

00:45:21.960 | if your body temperature is in a particular range,

00:45:24.560 | not only can you go further,

00:45:26.360 | but you will go further if you want to.

00:45:30.640 | Said differently, if you heat up too much,

00:45:34.400 | you will stop or you will die.

00:45:37.240 | Typically people stop.

00:45:38.360 | There are individuals who will push to the point

00:45:40.200 | where they black out and die in the same way that,

00:45:42.720 | and please don't do this experiment.

00:45:44.520 | There are people who can sit down face to face

00:45:48.520 | and say, let's hold our breath

00:45:50.040 | and whoever breathes first loses.

00:45:53.480 | Some people will just go until it's painful

00:45:55.620 | and then they'll gasp and take a big breath.

00:45:58.140 | There are always those individuals

00:45:59.360 | who can override that reflex

00:46:01.160 | and they will go until they pass out, okay?

00:46:03.880 | And if you do that in water, you can very easily die.

00:46:06.520 | So please don't do that experiment.

00:46:09.080 | But there's a reflex that relates the body to the brain

00:46:14.080 | and the brain to the body that shuts off our effort

00:46:17.220 | when we get too hot.

00:46:18.920 | So what Craig and his colleagues and now others have done

00:46:21.920 | is to do a test in the laboratory

00:46:23.520 | where rather than ask people to run outside

00:46:26.460 | until they absolutely don't want to run anymore,

00:46:29.620 | you put them on a treadmill and you set the speed, okay?

00:46:32.620 | So they have to keep up with the treadmill

00:46:34.560 | and at some point they quit.

00:46:36.580 | And you take groups and you do those

00:46:41.220 | in different temperature environments.

00:46:44.260 | So some people are running in a nice chilly laboratory,

00:46:48.340 | they get their heart rate up,

00:46:49.420 | so maybe their heart rate goes from 40 or 50

00:46:53.380 | baseline heart rate, maybe it gets up to 80 or 100,

00:46:56.060 | and then they keep the rate of the treadmill going the same

00:46:59.760 | and they will just plateau.

00:47:00.780 | So they'll get into a steady state cadence or rhythm

00:47:03.500 | and their heart is beating at more or less a steady state.

00:47:05.620 | Eventually, they'll probably stop

00:47:07.220 | 'cause they have something else to do,

00:47:08.880 | but people will continue at that temperature

00:47:13.880 | and at that heart rate,

00:47:15.780 | unless you start turning up the temperature in the room.

00:47:18.820 | And at some point they will stop

00:47:20.940 | and they'll stop much earlier when it gets hot

00:47:24.020 | because of something called cardiac drift, okay?

00:47:27.020 | So let's say I'm running

00:47:28.700 | and I'm running at a steady cadence on this treadmill

00:47:31.300 | and my heart rate is 85 beats per minute

00:47:33.220 | or 100 beats per minute, doesn't matter.

00:47:34.700 | Let's say 100, just for sake of example.

00:47:37.440 | Well, just making the room hotter

00:47:39.660 | is going to increase my heart rate further,

00:47:42.380 | even though I'm at the same output.

00:47:44.780 | And the brain does a computation.

00:47:48.180 | It somehow figures out that there's a heat component

00:47:51.600 | that's increasing heart rate

00:47:52.820 | and there's an effort component from running

00:47:55.140 | that's driving heart rate.

00:47:56.700 | And if the heat component

00:47:58.220 | and the heart rate output from the effort

00:48:01.100 | get to hit a certain threshold, I stop, okay?

00:48:04.860 | And some of you may think,

00:48:05.980 | well, there are people who just run

00:48:07.420 | and run and run and never stop.

00:48:09.180 | Eventually, everyone stops.

00:48:11.340 | Maybe it's because the race ended.

00:48:12.620 | Maybe it's because everyone else quit.

00:48:15.060 | I actually saw some stuff online.

00:48:16.860 | There are these races

00:48:17.700 | where people just will continuously do the same loop

00:48:19.820 | until everyone else drops out

00:48:21.260 | and then one guy or gal keeps going past everybody.

00:48:25.380 | But typically it stops because the race is over

00:48:27.500 | or because people quit.

00:48:29.160 | Increasing temperature increases the rate of quitting

00:48:33.580 | in part, not entirely,

00:48:35.200 | but in part because of this thing called cardiac drift,

00:48:38.160 | which you've probably experienced

00:48:40.100 | if you've been out on a hot day and you're walking uphill,

00:48:42.220 | you might stop to take a breath.

00:48:44.140 | If you sit in a sauna, your heart rate will increase.

00:48:46.700 | Heat increases heart rate.

00:48:48.820 | Effort increases heart rate.

00:48:51.020 | At a steady effort, you'll have a steady heart rate.

00:48:53.260 | If you increase the heat in the environment

00:48:56.100 | that you're engaging in that steady heart rate,

00:48:58.880 | your heart rate will now go up due to cardiac drift

00:49:01.820 | and you will quit, okay?

00:49:03.980 | So Heller and colleagues have done experiments

00:49:07.180 | where they do Palmer cooling under these environments.

00:49:10.940 | And that's wonderful because not only

00:49:13.820 | does it enable people to go further and faster,

00:49:18.740 | for much longer,

00:49:20.300 | that's been shown statistically significant every time,

00:49:23.700 | but it also protects the brain and body

00:49:26.060 | against hyperthermia, overheating, coma,

00:49:28.740 | nerve injury, nerve death, and actual death, okay?

00:49:32.700 | So you can see why this is such a valuable tool.

00:49:35.680 | So what are they doing?

00:49:37.700 | Well, in this case too,

00:49:39.140 | they're having them cool their hands

00:49:41.820 | and they're cooling the palms.

00:49:43.380 | Cooling the bottoms of the feet is a little trickier,

00:49:45.660 | but cooling the face could actually work as well.

00:49:48.260 | And we're going to talk about cooling the face

00:49:49.660 | and how to incorporate this.

00:49:51.180 | So at this point,

00:49:52.220 | I've just really wanted to impress upon you,

00:49:56.100 | not impress you, but impress upon you,

00:49:58.580 | the fact that you have these three surfaces of your body

00:50:01.160 | that are very good at passing cold into the body

00:50:04.260 | such that it cools the core body temperature.

00:50:06.500 | And that's a good thing for health and safety.

00:50:09.820 | And in order to maintain work output

00:50:13.260 | over longer periods of time, or actually just do more work.

00:50:16.060 | I mean, to me, the result is just so staggering

00:50:18.100 | is the 100 to 180 pull-ups in the controls

00:50:21.420 | and then 600 pull-ups in the cooled individuals, right?

00:50:25.960 | They actually also feel mentally

00:50:28.580 | as if they can do more work.

00:50:30.140 | It's not just that they can,

00:50:31.560 | their willpower is adjusted somehow

00:50:34.660 | by these shifts in temperature.

00:50:36.820 | Now, before we continue and get to the exact ways

00:50:39.940 | that any number of us can start to use this information,

00:50:43.540 | I want to talk about the opposite thing, which is heating.

00:50:47.100 | And you have to remember that these surfaces,

00:50:50.420 | the palms and the bottoms of the feet and the face,

00:50:52.640 | were not just arranged with these AVAs,

00:50:55.780 | these special ways to pass blood from arteries to veins

00:51:00.780 | in order to cool us for better athletic performance

00:51:04.320 | or to heat us on cold days, but for both of those things.

00:51:09.220 | Now, Heller and colleagues and others have also explored

00:51:12.880 | how these can be used to heat up the core.

00:51:16.100 | There are times when we want to heat up our core.

00:51:19.240 | Typically, we hear that most of the heat

00:51:21.900 | escapes through our head,

00:51:23.180 | so we'll put on a hat when we go outside.

00:51:25.740 | That's actually not true.

00:51:27.880 | Most of your heat escapes through your face,

00:51:30.460 | the palms of your hands and the bottoms of your feet.

00:51:33.320 | Now you should know why that's the case.

00:51:35.380 | What this means is that for post-surgery patients

00:51:40.820 | or for people that are hypothermic,

00:51:43.240 | indeed, you want to heat the core, right?

00:51:45.540 | But actually, I was on a swim recently

00:51:47.820 | where a friend became hypothermic.

00:51:50.140 | He was kind of slurring his words

00:51:52.040 | and kind of staggering around

00:51:53.220 | when we got him back on the beach.

00:51:54.900 | We brought him over to the lifeguard station.

00:51:56.900 | He turned out to be fine.

00:51:57.900 | Again, this is why cold water swims

00:51:59.620 | are something that you really need to do in groups,

00:52:01.460 | not alone, and you really have to know what you're doing.

00:52:04.140 | There were reasons for why this happened that day.

00:52:07.980 | But we were, basically,

00:52:09.860 | people thought we were a little strange

00:52:10.980 | until they realized what was happening.

00:52:12.500 | We were walking down the beach,

00:52:13.520 | basically sandwiching him at our chest

00:52:16.180 | because we were still warmer than the ambient environment,

00:52:19.320 | the environment around us,

00:52:20.340 | and we were pushing our chests against him

00:52:23.120 | to try and warm him up to warm up his core.

00:52:25.500 | In retrospect, that was the wrong thing to do.

00:52:28.180 | In talking with Craig and talking to other colleagues

00:52:30.860 | that work on thermogenesis,

00:52:33.000 | what we should have done was warm the palms of his hands,

00:52:36.300 | the bottoms of his feet, and his face

00:52:38.760 | because that would insulate the heat loss.

00:52:41.620 | Now, he was very cold, so presumably,

00:52:43.660 | there was vasoconstriction of the veins at these locations.

00:52:47.880 | And so it's not clear

00:52:49.680 | that that would have been the only strategy to use,

00:52:51.780 | but they have explored how to heat up post-surgery patients.

00:52:56.120 | And one of the best ways to do that

00:52:57.520 | is to get warm socks on the bottoms of the feet,

00:53:00.060 | get gloves on the hands,

00:53:01.400 | and if it can be done safely, to warm the face.

00:53:03.580 | Now, of course, you don't want to obstruct respiration

00:53:05.500 | and things of that sort.

00:53:06.940 | But again, the ability to pass heat into the body

00:53:11.360 | or to remove heat to the body

00:53:12.900 | is best done through these three surfaces.

00:53:15.400 | I can't emphasize that enough.

00:53:17.280 | So I mentioned before that you want to cool the palms

00:53:20.820 | or the bottoms of the feet,

00:53:21.920 | although that's a little harder to do, or the face,

00:53:23.660 | but not so much that the blood vessels constrict

00:53:27.980 | because then you won't be able to pass cool into the body

00:53:30.380 | because those pipes got smaller,

00:53:32.660 | and therefore, you can't pass cool into the body.

00:53:35.760 | So how can you start to incorporate this?

00:53:37.660 | Well, Craig and colleagues have a company

00:53:40.380 | that they've spun out through Stanford.

00:53:43.080 | We'll talk about that when we sit down with Craig

00:53:45.180 | that has made engineered devices that are optimal for this

00:53:49.280 | that are going to keep those passages open,

00:53:52.640 | keep the size of those veins correct

00:53:55.020 | to pass cool into the body quickly

00:53:56.820 | for sake of elite sports performance

00:53:58.320 | and even recreational sports performance.

00:54:00.180 | But you can actually start to incorporate this.

00:54:02.700 | First of all, I always get asked,

00:54:05.720 | how cold should the water be?

00:54:07.140 | Should it be ice water?

00:54:08.580 | Should it be very cold water?

00:54:10.780 | The answer is no.

00:54:12.000 | If you want to experience some of this effect

00:54:15.740 | without a device,

00:54:16.920 | one thing you could do would be, for instance,

00:54:18.860 | to do, I don't know,

00:54:20.120 | I'll use the gym or the treadmill as an example.

00:54:22.780 | You could do your maximum number of pull-ups, stop,

00:54:26.540 | and then you could actually put your hands into

00:54:29.940 | or on the surface of a sink that is presumably stopped up

00:54:34.940 | with cool water.

00:54:37.220 | So not ice water, not freezing cold, but cool water.

00:54:42.120 | Slightly cooler than body temperature

00:54:45.400 | before you started training would be a good place to start.

00:54:48.940 | You do that for 10 to 30 seconds,

00:54:50.860 | then you could go back and do your next set.

00:54:54.180 | You would repeat the cooling.

00:54:55.700 | You would want to extend the amount of cooling somewhat.

00:54:57.980 | So you might want to do that for 30 seconds to a minute.

00:55:00.660 | This is not going to be perfect.

00:55:01.780 | You're going to have to play with how cold to make it

00:55:04.620 | in order to get the optimal effect.

00:55:06.620 | But you ought to see an effect nonetheless.

00:55:09.460 | The same is true if you're running and you're fatiguing,

00:55:12.860 | obviously you don't want to become hyperthermic,

00:55:15.320 | cooling the hands or the bottoms of your feet or the face

00:55:18.820 | would be the ideal way to dump heat

00:55:20.620 | in order to be able to generate more output.

00:55:23.740 | Now, the face is something

00:55:25.220 | that we haven't talked a lot about.

00:55:27.620 | Everything I've told you up until now

00:55:29.020 | also says that if you are somebody who tends to get cold

00:55:31.820 | when you are outside, say in the winter or even in the fall,

00:55:35.140 | you tend to run cold, warming your face

00:55:38.140 | is going to be the most important thing that you can do.

00:55:40.820 | Now, it's kind of hard to do that without looking strange,

00:55:43.220 | like wearing a ski mask or something like that,

00:55:45.300 | but that is going to be more effective

00:55:47.300 | than covering and warming any other part of your body.

00:55:50.500 | Although it would be quite strange

00:55:51.580 | if you only had a ski mask on

00:55:52.920 | and you weren't wearing clothes anywhere else on your body.

00:55:54.900 | I don't recommend doing that outside.

00:55:56.940 | That will get you into all sorts of other kinds of trouble.

00:55:59.220 | It wouldn't be good for anybody.

00:56:00.920 | But now you understand the principle and the locations

00:56:04.500 | at which to deliver heat and cold.

00:56:06.640 | So let's say that you are out for a run

00:56:09.700 | and you want to incorporate this cooling mechanism.

00:56:12.380 | I talked to Craig about this.

00:56:13.460 | I said, what would be the kind of poor person's approach

00:56:16.720 | to this before this device is commercially available?

00:56:19.180 | And he said, well, you could take a frozen juice can

00:56:24.180 | if you have one of those or a very cold can of soda

00:56:26.980 | and you would want to pass it back and forth

00:56:29.960 | between your two hands.

00:56:31.640 | The reason the passing back and forth is really important

00:56:34.340 | is because you, again, you don't want it to be so cold

00:56:36.380 | that you constrict those venous portals

00:56:40.240 | that will allow cold to go into the body.

00:56:43.280 | Now, there are certainly people

00:56:45.600 | that are working on bike handles

00:56:47.340 | and that can actually cool the hands.

00:56:49.740 | You can expect with the Olympics coming up,

00:56:51.380 | people are aware of these data

00:56:52.940 | and are starting to incorporate it into a number of things.

00:56:55.540 | Here's what you don't want to do.

00:56:57.260 | And there are sports teams that I won't mention

00:56:59.220 | by name or brand that have made this mistake

00:57:01.320 | and it costs them dearly.

00:57:03.920 | You don't want to cool the core

00:57:06.320 | if you want to cool the body, right?

00:57:09.220 | If it's a very hot day and you're going to train,

00:57:11.660 | getting into an ice bath first, sure, it will cool you down

00:57:16.460 | but that's not going to be as effective

00:57:18.680 | as cooling the palms, the bottoms of the feet and the face.

00:57:21.700 | I have a friend who does some important work in this space

00:57:26.420 | with people in various, let's just say cultures

00:57:29.140 | where heat is generated quite a lot

00:57:31.020 | and they need to dump heat, ice packs delivered to the face

00:57:34.440 | are something that they actually use

00:57:36.160 | in order to dump heat quickly.

00:57:38.000 | Now, again, you don't want to keep the ice pack on your face.

00:57:40.880 | These are people that are very high work output, right?

00:57:43.720 | Firefighters and similar and very high work output.

00:57:47.460 | And then they'll put this,

00:57:49.080 | essentially it's like a cool face mask on their face.

00:57:53.040 | It'll allow their core body temperature to come down

00:57:54.860 | and then they remove it.

00:57:55.700 | They're not keeping it on there so long

00:57:57.080 | that they're getting the vasoconstriction, okay?

00:57:59.820 | So there are a number of ways that you could do this.

00:58:02.060 | And again, I'm not giving specific temperatures

00:58:04.740 | because it depends on how hot that day

00:58:06.220 | and how hot your body temperature is.

00:58:07.620 | So you can see why there's a need

00:58:08.740 | to create more devices for this

00:58:11.040 | but you can see a considerable improvement in endurance,

00:58:16.040 | in strength and in all kinds of explosive

00:58:20.100 | and sort of explosive power type output in athletics

00:58:24.340 | by using these surfaces of the hands

00:58:27.220 | and bottoms of the feet and face.

00:58:30.000 | The one that I've tried

00:58:31.520 | because in anticipation of this episode

00:58:33.880 | was the dips where then I would cool my hands.

00:58:37.500 | I actually decided to cool the bottoms of my feet as well

00:58:39.600 | because it just feels good

00:58:40.500 | and it's particularly hot out lately.

00:58:41.740 | So no shoes or socks on,

00:58:43.780 | put my feet into the bottoms of my feet

00:58:46.640 | just kind of hovering about a centimeter or two

00:58:49.100 | below the surface of a bucket of water

00:58:51.320 | that was just slightly, it felt cool,

00:58:53.300 | slightly cooler than body temperature or so.

00:58:56.800 | It just basically what came out of the spigot

00:58:58.620 | after I let it run for a little bit.

00:59:00.580 | And indeed I saw a 60% increase

00:59:03.740 | in the number of dips I can do in a single session.

00:59:05.960 | So it's actually a quite significant effect

00:59:08.500 | and you don't have to be perfectly precise

00:59:10.220 | in order to do it.

00:59:11.560 | And of course, if you want to heat up for whatever reason,

00:59:14.100 | like you're in, you're camping

00:59:16.040 | or you're lost in the environment,

00:59:17.580 | remember these three surfaces

00:59:19.280 | are going to be the best way to heat your core as well.

00:59:22.360 | So up until now, we've been talking about

00:59:24.340 | how to use cold during a workout

00:59:26.500 | in order to improve performance.

00:59:28.560 | And indeed cold applied to the appropriate parts of the body

00:59:31.960 | the appropriate times can vastly improve our performance

00:59:36.700 | in endurance and strength.

00:59:38.040 | Now I want to talk about the use of temperature

00:59:41.180 | in particular cold to improve the speed

00:59:44.940 | and the depth of recovery.

00:59:47.880 | Recovery is obviously vital, right?

00:59:50.420 | During a weight training session

00:59:51.860 | or during an endurance session,

00:59:53.580 | that's just the stimulus for getting better the next time.

00:59:56.420 | And if you don't recover,

00:59:57.680 | you not only won't get better, but you'll get worse.

01:00:00.340 | There's a lot of interest in the use of cold

01:00:04.400 | in order to improve recovery in the short term.

01:00:08.420 | We see this and probably the best example of this

01:00:10.840 | would be fighters in combat sports between rounds

01:00:14.540 | or athletes in between quarters or halftime.

01:00:19.180 | That's one form of recovery.

01:00:20.620 | The ability to go back into the sport very soon

01:00:23.700 | on an order of minutes, anywhere from like one minute

01:00:26.280 | in between rounds in typical combat sports

01:00:28.820 | or several minutes at a halftime, et cetera.

01:00:31.340 | Typically, what we see is people cooling their core,

01:00:37.380 | cooling the back of their neck,

01:00:38.980 | cooling the top of their head.

01:00:40.020 | So it might be a sponge with cold water

01:00:42.860 | over the top of the head

01:00:44.020 | or an ice pack on the back of the neck,

01:00:45.960 | or in some case even wearing cold ice vests.

01:00:49.640 | This has actually been done.

01:00:51.580 | That's going to be a very inefficient way

01:00:53.720 | to improve recovery of that kind.

01:00:56.100 | Far better would be to cool the face,

01:00:58.980 | the palms of the hands or the bottoms of the feet

01:01:00.820 | for the reasons that I described up until now.

01:01:03.180 | Submerging the body in an ice bath or taking a cold shower,

01:01:07.460 | say up to the neck or up to the chest

01:01:11.380 | or getting under cold water or jumping in a cold lake

01:01:14.020 | or something of that sort,

01:01:15.320 | or in the locker room getting under the cold shower

01:01:17.780 | also would be a terrible way to cool off the body quickly

01:01:21.860 | compared to the ways that I described

01:01:24.420 | through the palms of the hands, the bottoms of the feet

01:01:26.500 | or the face for the following reason.

01:01:29.300 | First of all, it's not optimizing those portals

01:01:31.860 | of the face, palms, the hands and the feet.

01:01:34.100 | And in addition, if it's very cold and you submerge

01:01:37.980 | or you cover a lot of the body with that cold,

01:01:41.680 | you're going to cause constriction of the very vessels

01:01:44.980 | and pathways that allow the body to efficiently dump heat.

01:01:49.180 | So again, the key thing is to cool these one or two

01:01:54.220 | or three of these surfaces,

01:01:55.780 | but not so cold that you cause the vasoconstriction.

01:01:59.700 | So what does this mean for you?

01:02:01.260 | It means that getting in an ice bath or a cold shower

01:02:04.940 | or putting an ice pack on the back of your neck

01:02:07.460 | in most cases is not going to be as good

01:02:09.740 | as splashing cold water on your face

01:02:11.540 | or even just holding your face with a damp cool cloth

01:02:15.100 | or something of that sort.

01:02:16.660 | It's so it's kind of counterintuitive.

01:02:19.380 | You think, oh, if I just jump into an ice bath,

01:02:21.580 | I'm going to cool down much faster

01:02:23.480 | than if I just cooled these one or two or three

01:02:27.020 | of these select regions of the body,

01:02:28.360 | but that's actually not the case.

01:02:30.220 | And then of course there's recovery that occurs

01:02:32.380 | from session to session.

01:02:33.760 | So outside of the game or the match or the exercise session.

01:02:37.760 | And many people are now relying on things like cryotherapy,

01:02:43.740 | which requires a lot of expensive equipment,

01:02:45.480 | big liquid nitrogen driven machine.

01:02:49.800 | Those aren't so common for most people

01:02:51.660 | or accessible for most people.

01:02:53.100 | But a lot of people are using cold baths

01:02:54.600 | or ice baths or cold showers.

01:02:56.800 | And again, that's not going to optimize recovery.

01:02:59.940 | In fact, it's going to have an additional effect

01:03:02.300 | that is going to potentially block the training stimulus.

01:03:06.200 | When you get into an ice bath,

01:03:07.660 | indeed there are provided it's not very, very cold.

01:03:11.900 | If you get into a cold shower

01:03:12.880 | provided it's not very, very cold,

01:03:14.260 | you are indeed blocking some of the inflammation

01:03:17.700 | that occurs because of the training session.

01:03:20.260 | But in doing so, you also are blocking pathways

01:03:24.040 | such as mTOR, mammalian targeted rapamycin,

01:03:27.420 | which are involved in the adaptation

01:03:29.500 | for a muscle to become stronger or bigger.

01:03:32.060 | Put simply, covering the body in cold

01:03:35.220 | or immersing the body in cold after training

01:03:38.940 | can short circuit or prevent the hypertrophy

01:03:41.500 | or muscle growth response.

01:03:43.500 | It has other effects that can be positive, right?

01:03:46.020 | It can induce thermogenesis, et cetera.

01:03:48.300 | It can reduce inflammation,

01:03:49.620 | but it can prevent some of the positive effects of exercise.

01:03:53.700 | Now, it hasn't been examined so much for endurance work,

01:03:56.920 | but let's say you come back from a round of endurance work,

01:04:00.040 | a run or a bike or a swim,

01:04:02.940 | getting into a cool bath or cooling the palms,

01:04:07.180 | the bottoms of the feet or the face,

01:04:08.480 | in my opinion, based on the science,

01:04:10.260 | would be better than completely immersing the body

01:04:13.780 | in the ice bath or the cold shower.

01:04:16.540 | There is a time and a place for the use of the ice bath

01:04:19.340 | or the cold shower or the cold plunge.

01:04:21.380 | Those tend to be when you want

01:04:23.860 | to deliberately increase brown fat thermogenesis

01:04:27.140 | or when you want to deliberately work on mental resilience.

01:04:31.700 | And in a subsequent episode on fat loss,

01:04:33.740 | I'm going to talk about how to optimize the use of cold

01:04:36.040 | specifically for increasing metabolism and fat loss.

01:04:40.060 | But for now, since we're talking about the use of cold

01:04:43.260 | for improving performance and recovery,

01:04:46.300 | the suggestion that I'm going to provide

01:04:48.300 | is based on the work of Craig Heller and colleagues

01:04:51.060 | that I've been talking about, as well as a excellent book.

01:04:53.900 | I mainly rely on textbooks and special volume books,

01:04:57.820 | which are collections of papers from experts

01:05:00.020 | in a particular area that go beyond standard

01:05:02.140 | kind of college level textbooks.

01:05:03.840 | The one that I've been relying on is called

01:05:05.220 | "Thermal Regulation and Human Performance,

01:05:07.500 | Physiological and Biological Aspects" by F.E. Marino.

01:05:11.360 | I don't know the publisher, I don't know the author.

01:05:13.820 | I do recognize some of the names

01:05:15.140 | of the particular papers there,

01:05:16.380 | but I just want to be clear there's no sort of

01:05:18.180 | business relationship or deal with them,

01:05:20.280 | but it's an excellent text.

01:05:21.300 | It's called "Thermal Regulation and Human Performance."

01:05:23.360 | You can find it online if you want to go

01:05:25.620 | really deep into this.

01:05:26.900 | But basically what they show is that

01:05:28.460 | if you can cool the body back to its resting temperature,

01:05:32.240 | by resting temperature I mean within the range

01:05:36.180 | that you would see at any time of waking day,

01:05:38.900 | but not in exercise.

01:05:40.540 | So just bringing the body temperature down to baseline.

01:05:44.620 | If you can do that, the sooner you can do that

01:05:46.760 | after a workout, the sooner that the muscle will recover,

01:05:50.460 | that the tendons will recover, and that the person, you,

01:05:53.300 | can get back into more endurance training,

01:05:55.520 | more weight training, et cetera.

01:05:57.120 | So cold actually can be a very powerful tool for recovery,

01:06:01.040 | but to maximize return to baseline levels of temperature,

01:06:04.760 | it's my belief based on the studies

01:06:08.300 | that are published in this book,

01:06:09.780 | as well as my discussions with my colleague Craig Heller,

01:06:12.180 | and in reviewing the literature overall,

01:06:14.940 | that just simply cooling the entire body

01:06:16.940 | by jumping into an ice bath or a cold shower

01:06:19.020 | is not the best way to go.

01:06:20.480 | You really want to rely on one of these three

01:06:23.100 | glabrous skin portals of the palms,

01:06:24.940 | the bottoms of the feet, or the face.

01:06:27.020 | So now you probably know more than you ever wanted to know

01:06:30.380 | about how we regulate body temperature

01:06:32.240 | and how it can be applied to exercise,

01:06:34.820 | both during the exercise session

01:06:37.120 | and afterward to optimize recovery.

01:06:41.260 | Many of us, all of us presumably,

01:06:43.640 | are also eating and drinking things

01:06:45.520 | and taking things at various times

01:06:47.380 | that can impact this process.

01:06:49.660 | And so because of that, we should ask

01:06:53.040 | whether or not those things are impacting body temperature.

01:06:56.660 | And when we do that, we find that there are certain things

01:06:59.380 | that many of us are doing

01:07:00.360 | that are actually impairing our performance.

01:07:03.380 | So for instance, if you are taking a pre-workout drink

01:07:06.580 | or you're ingesting a lot of caffeine or other substance

01:07:09.940 | to bring your body temperature up before exercise,

01:07:13.600 | you are limiting the amount of exercise that you can do.

01:07:16.700 | I can recall a time in college

01:07:19.600 | when I would drink a lot of espresso.

01:07:22.220 | Back then ephedrine was sold over the counter.

01:07:25.860 | I remember taking it.

01:07:26.980 | It will really energize you for workouts.

01:07:30.140 | You can generate a lot of energy

01:07:33.060 | and get extremely focused taking those things.

01:07:35.180 | They do increase heart rate.

01:07:36.300 | They can be quite dangerous.

01:07:37.820 | I don't recommend people take them.

01:07:39.180 | In fact, I think ephedrine is now off the shelves

01:07:41.640 | as a non-prescription compound

01:07:44.660 | because various people died from taking it

01:07:46.520 | who were sensitive to it or exercised in heat.

01:07:49.220 | But looking back at that,

01:07:50.700 | I realized it was a foolish approach.

01:07:53.100 | It was increasing core thermogenesis.

01:07:55.300 | Sure, I might've burned a few more calories,

01:07:57.820 | but actually when I look at the data

01:08:00.240 | that are coming from specific cooling

01:08:02.940 | and how that can so increase in performance

01:08:06.520 | if done properly,

01:08:07.940 | and then I compare that to the effects

01:08:10.020 | of taking some sort of thermogenic compound,

01:08:12.460 | whatever it is, some pre-workout or some pill

01:08:15.020 | or high levels of caffeine,

01:08:17.140 | it's very clear that increasing body temperature

01:08:20.340 | prior to working out is the exact wrong thing

01:08:22.940 | that one would want to do.

01:08:24.360 | You don't want to stay so cold

01:08:25.900 | that you can't generate good muscle contractions.

01:08:27.940 | You don't want to be like I am coming out of the cold ocean

01:08:31.540 | with claws for hands,

01:08:33.100 | but one wants to have your body temperature

01:08:35.980 | in a range that still allows you to work hard

01:08:38.780 | and perform well.

01:08:40.020 | Now, in terms of recovery,

01:08:43.580 | things like alcohol, we know are vasodilators.

01:08:46.980 | So those are going to cause people to drop body temperature.

01:08:50.420 | So you might think, oh, well, that sounds great for recovery.

01:08:52.540 | And I don't think people should be drinking

01:08:54.500 | who have problems with alcohol intake,

01:08:57.700 | alcoholics or they're not of drinking age, et cetera.

01:09:00.380 | I'm not a drinker,

01:09:01.400 | but I do have a good friend who's a quite accomplished athlete

01:09:04.140 | who basically drinks a beer or two

01:09:06.460 | after his long runs or cycling.

01:09:09.720 | And his argument is, well, I'm dumping body heat

01:09:12.640 | and I like a beer and he's probably right.

01:09:15.060 | It's probably a really good tool

01:09:16.480 | provided you don't have issues with alcohol

01:09:18.400 | that would preclude that as a tool

01:09:20.140 | or you're not of drinking age.

01:09:21.660 | But anything that you ingest after exercise

01:09:26.300 | that would increase body temperature

01:09:28.040 | is going to impede recovery.

01:09:29.980 | Anything that you do that lowers body temperature

01:09:32.200 | provided it's in safe ranges is going to accelerate recovery.

01:09:37.200 | And that brings us to the whole host of compounds

01:09:39.860 | that people take that can increase body temperature.

01:09:44.300 | And many people are taking these things

01:09:45.920 | in order to increase fat burning and increase metabolism.

01:09:49.180 | But in my opinion,

01:09:50.420 | it's impeding their ability to perform well.

01:09:53.380 | And especially if the performance is something

01:09:55.980 | that you're focused on aside from body recomposition,

01:09:59.900 | losing fat, building muscle.

01:10:01.620 | But even if you're focused on losing fat, building muscle,

01:10:04.000 | you have to ask yourself,

01:10:05.000 | is the body temperature increase

01:10:07.120 | that I'm getting from these compounds really worth it?

01:10:10.180 | Given that it can block or prevent my performance

01:10:14.220 | from being as good as it could.

01:10:16.400 | In other words, is it worth taking something

01:10:18.320 | that makes you feel very energized to go work out,

01:10:20.380 | but then you now know that you are stopping earlier

01:10:23.540 | and you're performing less well,

01:10:24.980 | fewer reps, fewer steps overall.

01:10:27.860 | Is it worth it if you had not taken that thing,

01:10:30.620 | then you could perform much longer

01:10:33.700 | and at much higher capacity.

01:10:36.020 | Some of you are probably saying, well, that's ridiculous

01:10:39.260 | because when I drink a quadruple espresso

01:10:41.980 | and I pop a whatever pre-workout or drink a pre-workout,

01:10:45.420 | then I know I can go much further.

01:10:47.660 | Ah, that might be true,

01:10:49.920 | but the increase in temperature is also costing you

01:10:52.480 | on the recovery side.

01:10:53.940 | And unless you're doing other things

01:10:56.120 | to improve your recovery,

01:10:57.540 | and I know many people that are, I don't judge,

01:10:59.340 | but many people who are doing those things

01:11:00.880 | are also augmenting their recovery

01:11:02.340 | through hormone augmentation

01:11:03.840 | and other performance enhancing tools,

01:11:07.340 | then for the typical person who's not doing that,

01:11:09.700 | it's probably shooting yourself in the foot.

01:11:11.700 | So let's take a look at what some of those compounds are

01:11:14.080 | and what they do, and just briefly review

01:11:16.620 | whether or not they would be a good or a bad idea to include

01:11:19.380 | if your main goals are performance

01:11:21.640 | or your main goals are body recomposition or both.

01:11:24.580 | So let's just briefly discuss stimulants.

01:11:26.600 | This could be caffeine,

01:11:27.620 | this could be any other kind of stimulant

01:11:30.220 | that are typically in a pre-workout drink

01:11:33.220 | or anything that might get you revved up before exercising.

01:11:36.380 | This could even be very strong tea.

01:11:38.120 | I've mentioned I'm a big consumer of mate.

01:11:40.180 | I like a yerba mate, I love that stuff.

01:11:43.300 | And I also drink caffeine.

01:11:45.220 | I drink, I love coffee of various kinds,

01:11:46.940 | mushroom coffee, black coffee, espresso, et cetera.

01:11:49.540 | I'm a chronic caffeine user.

01:11:52.940 | I don't think I'm an addict,

01:11:54.340 | but I'm a chronic caffeine user,

01:11:56.980 | meaning when I drink caffeine,

01:11:58.820 | my heart rate doesn't increase so much

01:12:01.020 | that it feels like a shock to my system.

01:12:03.660 | Some people are not caffeine adapted

01:12:05.680 | or they're very caffeine sensitive.

01:12:07.700 | Here's the straightforward rule.

01:12:09.900 | Caffeine for somebody who doesn't drink caffeine very much

01:12:14.140 | will constrict the blood vessels

01:12:15.940 | and will increase retention of body heat.

01:12:18.820 | And it's probably a bad idea before exercise.

01:12:21.740 | For somebody who's caffeine adapted

01:12:24.540 | and is used to drinking caffeine,

01:12:26.580 | it won't have that vasoconstriction effect.

01:12:28.580 | That's what the data point to because I'm adapted to it.

01:12:32.180 | But it will cause vasodilation

01:12:34.500 | and will allow me to dump body heat.

01:12:35.940 | So for me, I use it before I train

01:12:38.380 | or do any kind of exercise

01:12:39.800 | because I tend to do that early in the day,

01:12:41.340 | it won't prevent me from sleeping

01:12:42.700 | and it causes vasodilation.

01:12:44.860 | And then afterwards,

01:12:45.900 | I'm aware that it causes vasoconstriction

01:12:48.180 | after the caffeine wears off.

01:12:50.020 | So for somebody who drinks two or three or more

01:12:53.500 | cups of coffee a day or mate a day,

01:12:55.340 | so we're talking intake of anywhere

01:12:56.740 | from 100 to 400 milligrams of caffeine,

01:12:59.120 | what you want to do is you want to make sure

01:13:02.780 | that you would do that before exercise

01:13:06.100 | and probably not after exercise.

01:13:08.540 | That just makes logical sense

01:13:10.340 | given what we know about thermal regulation.

01:13:12.260 | And if you're somebody who doesn't drink caffeine,

01:13:14.660 | drinking caffeine before a workout

01:13:16.620 | is going to be about the worst thing

01:13:18.140 | that you could possibly do

01:13:18.960 | because it's going to increase core body temperature

01:13:21.100 | through its thermogenic effects

01:13:22.740 | and it's going to constrict your blood vessels

01:13:25.220 | and make it even harder to dump heat.

01:13:27.340 | So I don't suggest that people drink caffeine or not.

01:13:31.180 | I just suggest that you think about

01:13:33.180 | whether or not you're caffeine adapted or not

01:13:35.620 | and decide whether or not you want to drink caffeine.

01:13:37.900 | In general, you're going to be better

01:13:39.700 | not drinking any caffeine than you are drinking caffeine

01:13:43.380 | unless you're a heavy caffeine user or abuser,

01:13:45.900 | in which case not drinking caffeine

01:13:47.780 | is going to give you vicious headaches

01:13:49.400 | and is going to make it very hard to get motivated

01:13:51.780 | because you're just not used to it.

01:13:53.080 | It takes about three weeks to get used to no caffeine.

01:13:57.000 | It's brutal.

01:13:57.840 | I've done it before.

01:13:58.680 | I've done caffeine fast.

01:13:59.960 | I don't know that I ever want to do it again.

01:14:01.340 | That's how painful it was.

01:14:02.940 | But you get headaches because of the effects

01:14:05.160 | on vasodilation and constriction.

01:14:07.400 | If you like caffeine, use in moderate amounts

01:14:09.960 | and use it before your workout's not after.

01:14:11.980 | If you don't like caffeine or you don't use it very often,

01:14:14.220 | stay away from it anywhere close to exercise,

01:14:16.420 | before or after, for that matter.

01:14:18.840 | One of the more commonly used compounds

01:14:21.900 | that's sold over the counter

01:14:23.420 | are non-steroid anti-inflammatories.

01:14:26.260 | So things like Tylenol and Advil and other trade names

01:14:28.980 | and naproxen sodium, things of that sort.

01:14:31.120 | Almost all of those drop body temperature to some extent.

01:14:36.080 | And that's why it's often recommended

01:14:38.600 | that people take them when they have a fever.

01:14:40.640 | Although the whole business

01:14:42.460 | of dropping body temperature artificially

01:14:44.300 | when you have a fever is itself an interesting discussion

01:14:47.360 | whether or not that's the most adaptive

01:14:49.260 | or best thing to do.

01:14:50.300 | Certainly you don't want fever to go too high,

01:14:51.940 | can be very dangerous, can kill you.

01:14:53.920 | But artificially dropping body temperature

01:14:57.140 | with these compounds can be tricky.

01:14:59.540 | Now, a number of athletes, especially endurance athletes,

01:15:02.780 | will rely on these non-steroid anti-inflammatory drugs

01:15:06.200 | specifically to keep body temperature lower

01:15:09.260 | during long bouts of exertion.

01:15:11.540 | This is a little bit of a pharmacologic version

01:15:14.580 | of dumping heat instead of using Palmer cooling

01:15:19.420 | or face ice pack cooling,

01:15:22.620 | they're relying on pharmacology

01:15:24.100 | to drop their core body temperature.

01:15:26.400 | That has certain obvious advantages.

01:15:29.960 | Those advantages should be obvious

01:15:32.000 | and the reasons for them should be obvious

01:15:33.820 | based on everything we've talked about up until now.

01:15:35.700 | Lower temperature allows you to go further harder

01:15:37.600 | with more intensity.

01:15:39.500 | However, they do have effects on the liver

01:15:42.460 | and they can also have effects on the kidneys

01:15:45.020 | and during long bouts of exercise

01:15:46.800 | or even short bouts of exercise,

01:15:48.040 | water balance and salt balance

01:15:49.600 | are also going to be vital to maintain

01:15:52.500 | in order to perform well,

01:15:55.360 | generate the best muscle contraction,

01:15:57.060 | stay mentally alert and also to stay alive.

01:15:59.460 | We will do an episode on salt electrolytes

01:16:02.100 | and water and water balance,

01:16:04.480 | but you probably want to think carefully

01:16:07.080 | about whether or not you want to use

01:16:08.940 | non-steroid anti-inflammatories before any training session

01:16:12.400 | just for the performance augmentation effect,

01:16:15.420 | unless you're working carefully with a coach,

01:16:18.300 | whether or not you've done that in practices

01:16:20.460 | and of course, whether or not you are in a situation

01:16:24.260 | where monitoring your body temperature carefully

01:16:26.860 | is going to be important.

01:16:27.820 | You might ask, well, when would that be?

01:16:29.140 | Well, desert races, summer training in races, winter rides,

01:16:34.140 | you certainly don't want to get too cool either.

01:16:36.300 | So alcohol, caffeine and non-steroid anti-inflammatory drugs

01:16:41.260 | because of their effects on temperature

01:16:42.900 | will impact performance and recovery,

01:16:45.180 | but you want to be cautious about how you approach them.

01:16:47.480 | I personally am more a fan of using caffeine

01:16:51.200 | in moderate doses for the reasons I described before,

01:16:54.020 | as well to use the cooling of the palms,

01:16:56.660 | cooling of the bottoms of my feet, right?

01:17:00.100 | By placing them into a bucket

01:17:01.500 | or into a cool bath after training

01:17:04.860 | or cooling the face after training

01:17:07.180 | or sometimes even during training.

01:17:08.860 | It just seems like there's more of a margin

01:17:10.640 | to play with the variables,

01:17:11.860 | to heat up the water or cool it down a little bit,

01:17:14.840 | to include one palm or the other palm.

01:17:18.220 | There's just all sorts of good parameter space,

01:17:21.860 | as we call it in science, that you can play with

01:17:23.660 | and work with to find what works for you.

01:17:25.800 | Whereas when you pop a pill, sure, you can adjust the dose

01:17:29.540 | and you can adjust it next time,

01:17:31.000 | but once it's in you, it's in you,

01:17:32.400 | and there's going to be some period of time

01:17:34.060 | before you can modulate it.

01:17:35.900 | What I've offered today are ways

01:17:38.240 | in which you can use temperature

01:17:39.940 | to powerfully improve performance.

01:17:42.740 | And if you think about it,

01:17:43.580 | you can vary that from set to set.

01:17:45.380 | You could do your pull-ups or your sprints

01:17:48.000 | and then cool your palms

01:17:49.720 | and then try and go with colder water the next round

01:17:52.660 | or warmer water the next round

01:17:54.340 | or do both feet and palms and face.

01:17:56.360 | I mean, you can do all sorts of things moment to moment

01:17:58.600 | and see what works for you.

01:18:00.280 | Again, essentially zero cost or no cost.

01:18:02.860 | Whereas when you pop something, you take a pill,

01:18:06.240 | you're basically in that regimen

01:18:08.360 | for the next hour or two or more.

01:18:10.460 | You can always take more, but you can't really take less.

01:18:12.980 | You can't really extract it from your body in real time.

01:18:15.160 | So it doesn't give you a lot of opportunity

01:18:17.080 | to play scientist, which is what I like to do,

01:18:19.640 | because what I'm always trying to do

01:18:21.160 | is trying to dial in the best protocols possible

01:18:23.920 | based on the mechanisms and data.

01:18:25.520 | And if you can do that moment to moment,

01:18:26.920 | that places you in a position of power.

01:18:29.240 | Once again, we've covered a lot of material.

01:18:31.880 | By now, after seeing this episode

01:18:34.000 | or listening to this episode,

01:18:35.980 | you should understand a lot about how your body heats

01:18:38.760 | and cools itself and the value of that

01:18:41.140 | for physical performance.

01:18:43.240 | I hope you'll also appreciate

01:18:44.480 | that you have tools at your disposal

01:18:46.420 | to vastly improve your physical performance.

01:18:49.480 | And should you try those, please let us know how it goes.

01:18:53.200 | If you decide to do Palmer cooling during your runs

01:18:55.660 | or after your runs, during your weight workouts,

01:18:58.760 | during your yoga sessions, whatever it is, let us know.

01:19:01.240 | Please place that in the comments.

01:19:03.380 | I've given you specific protocols and some direction,

01:19:06.760 | but I've also left it slightly vague

01:19:08.960 | because as I mentioned earlier,

01:19:11.000 | I don't know all the environmental conditions.

01:19:12.760 | I don't know how hot your yoga studio is

01:19:14.800 | or how cool your gym happens to be

01:19:16.520 | or your body temperature or time of day.

01:19:19.340 | Remember, your temperature will vary

01:19:21.080 | according to the time of day.

01:19:22.240 | We did a whole episode about that related to sleep.

01:19:24.700 | Typically, your body temperature is rising early in the day

01:19:27.800 | and is coming down as you approach the late evening

01:19:30.800 | and late night hours for sleep.

01:19:32.500 | In the middle of the night, your temperature is very low,

01:19:34.720 | at its absolute lowest,

01:19:35.720 | something we call the temperature minimum.

01:19:37.440 | So we don't know exactly where you're at.

01:19:40.100 | You need to take the information that you received today,

01:19:42.860 | and should you try and incorporate it,

01:19:45.100 | try and do it intelligently.

01:19:46.400 | Don't cool yourself off so much that you become cryogenic,

01:19:50.680 | and please don't warm yourself up.

01:19:52.520 | In fact, we didn't talk at all about warming yourself up

01:19:55.520 | because warming yourself up too much can be quite dangerous.

01:19:58.980 | You never, ever, ever want to be hypothermic.

01:20:01.500 | That's what your body and your brain are trying to avoid.

01:20:04.760 | We talked a little bit about supplements,

01:20:07.680 | but not the standard sorts of supplements

01:20:09.560 | I usually list off on these episodes.

01:20:11.520 | Rather, we talked about caffeine,

01:20:14.000 | non-steroid anti-inflammatories,

01:20:15.860 | and how those can impact temperature,

01:20:17.160 | how alcohol can impact temperature.

01:20:19.240 | And I should just mention in closing that every time we eat,

01:20:22.180 | we also increase temperature.

01:20:23.380 | There's a eating-induced thermogenic effect,

01:20:25.980 | but that's a minor one.

01:20:27.080 | That's a small one.

01:20:27.920 | So you wouldn't worry about eating before training

01:20:31.740 | because of its effects on temperature,

01:20:33.220 | because it tends to be really minor.

01:20:35.960 | Going forward, we're going to talk more about temperature

01:20:38.400 | and other ways to improve physical performance

01:20:41.780 | and skill learning.

01:20:42.640 | We're going to talk about specific ways

01:20:44.620 | to accelerate fat loss, to improve muscle growth,

01:20:48.740 | to improve suppleness and flexibility.

01:20:52.400 | These approaches and mechanisms are anchored deeply

01:20:56.560 | in neuroscience and physiology

01:20:58.360 | and the relationship between our peripheral organs,

01:21:00.800 | which include our skin, and our brain,

01:21:03.840 | and all the organs in between.

01:21:05.640 | So it's really a pleasure for me

01:21:07.180 | because I'm able to look to the textbook literature

01:21:10.460 | that exists and really came out

01:21:12.280 | over the last 50 to 100 years.

01:21:14.400 | And unlike a lot of areas of neuroscience,

01:21:16.380 | which are still sort of mystical,

01:21:18.240 | like consciousness and dreaming,

01:21:20.160 | of which we understand a little bit about,

01:21:22.180 | these core mechanisms of temperature and physiology,

01:21:24.600 | which are so powerful, involve very concrete studies

01:21:29.080 | that, as you learned today, are very actionable.

01:21:31.740 | If you're enjoying this podcast

01:21:34.200 | and you like the information that you're receiving,

01:21:37.180 | if you're incorporating it into your life in useful ways,

01:21:39.920 | please recommend the podcast to other people

01:21:41.900 | if you think they could benefit from it as well.

01:21:44.580 | Please subscribe to the podcast on YouTube,

01:21:47.280 | so you want to hit the subscribe button.

01:21:49.080 | As well, hit the notifications button.

01:21:51.120 | We come out with new episodes every Monday,

01:21:53.040 | but from time to time, we also release shorter content

01:21:56.280 | and we will be releasing additional content

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01:22:00.480 | If you don't already subscribe on Apple and/or Spotify,

01:22:04.080 | please do so.

01:22:05.060 | Also on Apple, you have the opportunity

01:22:06.840 | to leave us up to a five-star review,

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01:22:30.720 | That allows you to support the podcast

01:22:32.560 | at any level that you like.

01:22:34.640 | Today, we didn't focus so heavily on supplements,

01:22:36.700 | but in other episodes I have,

01:22:38.280 | and there are certainly supplements

01:22:40.120 | that are beneficial for sleep, for performance,

01:22:42.520 | for learning, immunity, and so forth,

01:22:45.840 | we've partnered with Thorne, T-H-O-R-N-E.com,

01:22:50.840 | because Thorne supplements,

01:22:52.880 | we believe to be the most stringent in terms of

01:22:56.460 | what they put on the bottle

01:22:57.840 | is actually what's in the bottle,

01:22:59.040 | so the amounts are precise,

01:23:00.300 | and the quality of the ingredients is very precise.

01:23:02.520 | They partner with the Mayo Clinic,

01:23:04.120 | all the major sports teams,

01:23:05.320 | so we're delighted that we're partnered with Thorne.

01:23:07.140 | If you want to see the supplements that I take,

01:23:09.080 | you can go to thorne.com/u/huberman,

01:23:13.800 | and you can see the supplements that I take.

01:23:15.460 | You could get 20% off any of those supplements,

01:23:18.160 | should you choose to order them,

01:23:19.400 | as well as 20% off any other supplements

01:23:21.880 | that Thorne happens to make.

01:23:23.500 | That's thorne, T-H-O-R-N-E.com/u/huberman

01:23:29.440 | to get 20% off any of the supplements that Thorne makes.

01:23:33.240 | And last but not least,

01:23:35.040 | I want to thank you for your time and attention.

01:23:36.820 | I realize this is a lot of information.

01:23:38.960 | I hope you'll find some of it to be actionable

01:23:40.680 | and useful for you and for people that you know,

01:23:43.080 | and as always, thank you for your interest in science.

01:23:45.760 | [upbeat music]

01:23:48.340 | [MUSIC PLAYING]

Supercharge Exercise Performance & Recovery with Cooling

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