Protocol for Instant Motivation & Alertness

00:00:00.000 | I'm now going to tell you a tool that you can use

00:00:04.560 | when you're feeling less than energized,

00:00:07.060 | less than motivated, and when you need to exercise

00:00:10.700 | and you don't feel like doing it,

00:00:12.340 | and when you want to leverage exercise

00:00:15.320 | as a way to improve brain function and plasticity.

00:00:18.320 | It all involves the vagus nerve,

00:00:21.080 | and it involves an aspect of the vagus nerve

00:00:23.160 | that very few people are aware of,

00:00:25.200 | but in my opinion, is one of the coolest aspects

00:00:28.380 | of the vagus nerve.

00:00:29.340 | It's at least as cool as vagal control

00:00:31.800 | over heart rate variability and auto-regulation,

00:00:34.440 | and it goes like this.

00:00:35.740 | There's a beautiful set of findings

00:00:38.680 | from a guy named Peter Strick at the University of Pittsburgh,

00:00:42.060 | who used these really cool methods

00:00:43.460 | for tracing connections between the brain and body

00:00:46.120 | to ask the question, what areas of the brain

00:00:49.260 | are communicating with our adrenal glands?

00:00:51.840 | Our adrenal glands are two glands

00:00:53.480 | that sit atop your two different kidneys,

00:00:55.600 | so one atop each kidney and release, as the name suggests,

00:00:58.680 | adrenaline.

00:00:59.680 | Adrenaline is also called epinephrine.

00:01:02.140 | Your adrenal glands also release cortisol,

00:01:04.500 | but for sake of this discussion,

00:01:06.420 | let's just think about adrenaline released from your adrenals.

00:01:09.320 | What he found through a bunch of experiments done

00:01:12.780 | in non-human primates, and that seemed to correspond very well

00:01:15.660 | to what we observe in humans as well,

00:01:17.920 | is that there are three general groups of brain areas.

00:01:21.260 | Motor activation areas, so what we call upper motor neurons.

00:01:24.640 | So these are the neurons in the brain that control the lower motor,

00:01:26.860 | neurons in the spinal cord that control the muscles of the body,

00:01:29.900 | as well as neurons within our brain that are involved in cognition

00:01:33.100 | and planning, and areas of the brain that are involved in emotion,

00:01:37.220 | that can communicate with the adrenals

00:01:39.260 | and cause them to release adrenaline.

00:01:42.160 | Now that's great, but it sort of points to a pathway whereby,

00:01:45.100 | okay, you know you should exercise,

00:01:47.540 | you tell yourself you should exercise,

00:01:49.220 | you're emotional about it,

00:01:50.700 | and your adrenals release adrenaline and you exercise.

00:01:54.600 | Now that's interesting, but what's perhaps far more interesting

00:01:58.740 | is that the data from Strick Lab and other labs as well,

00:02:02.740 | shows that when we move the large muscles of our body,

00:02:07.120 | the adrenals release adrenaline, epinephrine.

00:02:10.360 | Now epinephrine has an activating sympathetic nervous system,

00:02:14.460 | stimulatory effect, right?

00:02:15.740 | It tends to make the tissues of the body that are associated

00:02:18.380 | with movement and with so-called fight or flight,

00:02:21.080 | although again, fight or flight is kind of an extreme example,

00:02:23.800 | it tends to activate the organs of the body

00:02:27.300 | and make them more likely to be active.

00:02:29.440 | It increases the probability that movement will occur,

00:02:33.040 | overall body movement.

00:02:34.720 | So when we move the large muscles of our body,

00:02:36.700 | our legs, and in particular our trunk muscles,

00:02:38.920 | we release adrenaline,

00:02:40.960 | that adrenaline activates the organs of our body

00:02:43.600 | and further makes it likely

00:02:45.080 | that we're going to move our musculature more.

00:02:47.780 | But get this,

00:02:48.980 | adrenaline, epinephrine doesn't cross the blood brain barrier.

00:02:52.460 | So how does it increase our level of alertness in our brain,

00:02:55.700 | right?

00:02:56.540 | You don't want your body to be super active

00:02:57.480 | and your brain to be kind of sleepy.

00:02:59.120 | That's not good.

00:03:00.040 | That's not adaptive.

00:03:01.760 | It turns out that when the adrenals release adrenaline,

00:03:05.340 | it binds to receptors on the vagus nerve itself,

00:03:08.540 | those sensory axons that extend into the body.

00:03:12.060 | There are receptors on those wires, right?

00:03:14.220 | Not all the receptors are at one end or the other,

00:03:16.000 | they're also on those axons.

00:03:18.620 | The adrenaline binds to the receptors on those axons

00:03:21.020 | and the vagus nerve in turn releases glutamate,

00:03:25.640 | an excitatory neurotransmitter in a structure in the brain

00:03:28.640 | called the nucleus tractus solitaris.

00:03:31.540 | The neurons in what I'm just going to call the NTS

00:03:33.580 | for simplicity, in turn, activate neurons in a brain structure

00:03:38.160 | called the locus coeruleus.

00:03:40.300 | The locus coeruleus contains neurons that release

00:03:42.720 | what's called norepinephrine.

00:03:44.720 | And the neurons of locus coeruleus send their axons out

00:03:48.020 | very extensively across the brain

00:03:49.980 | in kind of a sprinkler system-like organization,

00:03:52.960 | such that when you move the large musculature of your body,

00:03:56.560 | you release adrenaline.

00:03:58.140 | That adrenaline activates the tissues of your body,

00:04:00.480 | makes them more likely to move,

00:04:01.840 | also binds to receptors on the vagus.

00:04:04.080 | The vagus nerve in turn releases glutamate,

00:04:06.220 | an excitatory neurotransmitter in the NTS.

00:04:08.640 | The NTS then passes off that excitatory signal,

00:04:11.780 | like a bucket brigade off to the locus coeruleus.

00:04:14.900 | The locus coeruleus dumps a bunch of norepinephrine into the brain

00:04:18.500 | and increases your levels of alertness.

00:04:20.740 | What this means is that the vagus nerve is central to the process

00:04:24.780 | of using physical activity to make your brain more alert.

00:04:28.700 | And we know that activation of locus coeruleus makes the brain areas

00:04:32.780 | that are involved in motivation and the propensity to move more

00:04:37.260 | higher in levels of activity.

00:04:39.580 | In other words, if you're not feeling motivated to exercise,

00:04:42.620 | or you're not feeling alert enough,

00:04:45.080 | movement of the body that includes especially the legs,

00:04:47.560 | the large muscles of the legs,

00:04:48.840 | the quadriceps, hamstrings, et cetera,

00:04:50.720 | as well as the trunk muscles of the body,

00:04:53.020 | stimulate this pathway in a kind of dominoing effect

00:04:56.700 | that makes the likelihood and believe it or not,

00:04:59.920 | the desire to move much more likely.

00:05:03.560 | This I've personally found to be an immensely useful piece

00:05:07.380 | of information because sure,

00:05:09.540 | I knew that sometimes I would go to the gym

00:05:11.720 | or I'd head out on a run and I wasn't feeling motivated,

00:05:14.880 | or I'd sit down to do some work and I'd feel kind of sleepy,

00:05:17.340 | despite the fact that I had slept pretty well the night before

00:05:19.320 | and eaten just fine and the room wasn't too warm, et cetera.

00:05:22.500 | And I feel kind of lethargic.

00:05:23.560 | And I was like, what's going on here?

00:05:25.660 | And yes, I had the experience of sometimes, you know,

00:05:29.120 | doing a bit of a warmup, maybe some light calisthenics,

00:05:31.540 | maybe a few warmup sets or jogging for a little while,

00:05:34.060 | and then finding that my levels of alertness increased.

00:05:36.600 | But I've also had just as often the experience of not feeling

00:05:40.500 | that motivation for physical activity

00:05:43.100 | or for cognitive activity come online,

00:05:45.420 | especially if I wasn't extremely interested in that activity

00:05:48.320 | or that thing that I was supposed to learn.

00:05:50.200 | You know, it's very easy to be excited

00:05:51.820 | when we want to do the activity or we want to learn the thing

00:05:54.200 | that we're supposed to be learning at a given moment

00:05:56.160 | or reading at a given moment.

00:05:57.660 | This pathway is immensely useful to understand

00:06:00.620 | because it explains why it is that even when you're not feeling motivated,

00:06:03.940 | if you do some activity that, yes, is preceded by a bit of a warmup.

00:06:07.880 | So maybe, I don't know, you do some light calisthenics

00:06:09.800 | or you go on the treadmill for a few minutes walking,

00:06:11.600 | then maybe a little bit faster,

00:06:12.580 | that it can increase your levels of alertness and motivation.

00:06:16.280 | But it especially explains how if you put in some effort that at the moment feels like a big exertion,

00:06:23.740 | your entire body and brain state shifts in a way that levels of motivation and energy to do more physical work

00:06:31.240 | or more cognitive work or both increases dramatically.

00:06:34.680 | And these are not small effects when they've been measured.

00:06:36.840 | In fact, for all the talk that's out there in kind of pop psychology and in kind of pop neuroscience

00:06:43.360 | about the vagus being a calming pathway, all the neurophysiologists out there,

00:06:49.640 | and I know there aren't very many, but I'm friends with a lot of neurophysiologists,

00:06:52.840 | they'll all tell you that if they're doing a surgery or they're doing some sort of brain recording

00:06:58.340 | and the animal or person that they're doing the brain recording from

00:07:01.760 | is starting to drop into a state of deep parasympathetic activity,

00:07:06.420 | they're falling asleep or they need to be more alert, what do they do?

00:07:09.360 | They stimulate the vagus.

00:07:10.980 | They stimulate the vagus nerve in order to wake up the brain.

00:07:13.920 | In fact, stimulating the vagus has been used to save people's lives

00:07:17.240 | when they are drifting too far down into deeper and deeper planes of anesthesia.

00:07:21.920 | So stimulating the vagus wakes up the brain.

00:07:25.120 | And the way to stimulate the vagus is by way of these receptors on the vagus nerve itself.

00:07:29.700 | And the way to do that without an electrical stimulator, right?

00:07:32.600 | Because we're not talking about clinical conditions here,

00:07:34.180 | in order to increase levels of motivation, alertness, and focus for physical activity

00:07:38.700 | or cognitive activity and learning, et cetera,

00:07:40.700 | or simply to overcome lethargy and brain fog,

00:07:43.500 | is to do some sort of physical activity that includes the large musculature of your body.

00:07:47.640 | These could be things like jumping.

00:07:49.680 | These could be things like actual resistance training.

00:07:52.700 | This could be running.

00:07:54.680 | This information really points to the idea of, of course, after a good warmup,

00:07:58.900 | doing more sprinting type activity, more strength type activity,

00:08:03.820 | you know, six repetitions or less where you're getting close to failure,

00:08:07.020 | this sort of thing to wake up the brain and body,

00:08:09.160 | as opposed to doing long rhythmic activity that's below the threshold

00:08:13.420 | of what would activate a lot of adrenaline from the adrenals.

00:08:16.320 | So the idea is to get those adrenals to release adrenaline into your system.

00:08:19.540 | It won't cross the blood-brain barrier,

00:08:21.060 | but your vagus nerve provides this beautiful link

00:08:23.800 | between the body and brain to match levels of excitation

00:08:26.920 | from the body to the brain, and you can leverage that.

00:08:29.980 | So the idea is to get those adrenals to the body.

Protocol for Instant Motivation & Alertness | Dr. Andrew Huberman

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