How to Use Exercise to Improve Your Brain’s Health, Longevity & Performance

In this episode, I discuss how different forms of exercise impact brain health and performance in both the short and long term. I explain how many of the positive effects of exercise on brain function occur through the action of specific neurochemicals that increase alertness. I also cover how to best time exercise and which specific types of exercise to include in your weekly routine to maximize benefits for your brain. Additionally, I explain how certain types of exercise trigger the release of a hormone from your bones called osteocalcin, as well as brain-derived neurotrophic factor. Together, these substances increase neuroplasticity and enhance learning. The positive effects of exercise on brain oxygenation, blood supply, and fuel utilization are also discussed. Listeners will learn how to design a weekly exercise program that optimizes physical fitness, brain health, longevity, and performance, along with the mechanistic logic behind those recommendations. Find show notes with articles, resources and more at hubermanlab.com. Pre-order Andrew's upcoming book, Protocols: https://go.hubermanlab.com/protocols Thank you to our sponsors AG1: https://drinkag1.com/huberman BetterHelp: https://betterhelp.com/huberman Helix Sleep: https://helixsleep.com/huberman David: https://davidprotein.com/huberman Function: https://functionhealth.com/huberman Maui Nui: https://mauinui.com/huberman Timestamps 00:00:00 Exercise, Brain Health & Performance; Protocols Book 00:04:03 Sponsors: BetterHelp & Helix Sleep 00:06:55 Brain Health, Cardiovascular & Resistance Training 00:11:51 Exercise & Positive Impact on Brain Performance; Arousal 00:18:20 Learning & Arousal 00:23:18 Sponsors: AG1 & David 00:26:01 Exercise & Acute Learning 00:29:16 Tool: High-Intensity Training & Cognitive Flexibility; Over-Training 00:33:32 Long-Term Brain Health; Tool: Exercise “Snacks”, Cognitive Performance 00:36:57 Exercise, Brain & Body Energy, Adrenaline, Norepinephrine 00:44:08 Adrenal “Burnout”?; Exercise to Increase Energy, Adrenaline 00:48:20 Tool: Core, Compound Movements; Mind-Body Connection 00:53:58 Sponsor: Function 00:55:45 Bones, Osteocalcin, BDNF & Hippocampus; Tool: Jump Training 01:01:30 Exercise, Fuel, Multifactorial Pathways; BDNF & Activity 01:05:06 Lactate, Astrocytes & Brain Function; VEGF & Brain Health 01:11:17 Tools: Zone 2, High-Intensity Training, Time Under Tension Training 01:19:54 Sponsor: Maui Nui 01:21:37 Tools: Time Under Tension; Explosive Jumping, Eccentric Control Training 01:25:30 Injury & Exercise, Illness 01:28:09 Sleep; Injury, Sleep-Deprivation & Exercise 01:33:51 SuperAgers, Anterior Mid-Cingulate Cortex, Grit & Persistence 01:42:04 Tool: Embrace Challenges; Deliberate Cold Exposure, Rope Flow 01:47:39 Zero-Cost Support, YouTube, Spotify & Apple Follow & Reviews, Sponsors, YouTube Feedback, Protocols Book, Social Media, Neural Network Newsletter Disclaimer & Disclosures Learn more about your ad choices. Visit megaphone.fm/adchoices

Speaker names marked ? are inferred from speaking time and the show’s known hosts — they are not voice-verified.

• 0:00Andrew D. Huberman?

  Welcome to the Huberman Lab Podcast, where we discuss science and science-based tools for everyday life.

• 0:09Andrew D. Huberman?

  I'm Andrew Huberman, and I'm a professor of neurobiology and ophthalmology at Stanford School of Medicine. Today, we are discussing exercise and brain health, which includes brain longevity and brain performance, our ability to learn new information over long periods of time, and indeed, into old age. Today, we are going to discuss how different forms of exercise, resistance training, cardiovascular training of both long, medium, and short duration, can be used to improve the way that your brain functions acutely, meaning immediately, in the minutes and hours and the day that you do that exercise, as well as in the long term, in the days, weeks, and months after you perform that exercise. And of course, if you're exercising regularly,

• 0:53Andrew D. Huberman?

  the effects of exercise on brain health and performance compound over time, making you better able to learn things, better able to retain information from the past, and indeed, to expand your brain's capacity to learn new types of information in new ways. In researching today's episode, I quickly came to realize that the number of studies that have explored the relationship between exercise, brain performance, and brain health, as well as the range of different types of exercise that have been explored in that context, is extremely vast. There are literally tens of thousands of studies on this topic, as well as meta-analyses and reviews, all of which point to positive effects of doing exercise of various types on brain health and performance. Within those many, many studies,

• 1:39Andrew D. Huberman?

  you'll find many, many different exercise protocols that lead to improvements in brain performance and longevity. So the goal of today's episode is to synthesize that vast amount of information into a logical framework that simplifies it and clarifies it and places it within the context of specific mechanisms, both neurobiological mechanisms and endocrine-based mechanisms, that together can very well explain the data on how exercise impacts brain health and longevity, such that by the end of today's episode, you'll have both. Some specific recommendations about how to use exercise for sake of brain health and performance that I believe will be new to most of you, as well as the ability to think about the mechanisms and the logical framework that wraps around this incredibly large literature

• 2:23Andrew D. Huberman?

  on exercise and brain performance, so that you can customize your exercise program on the basis of how much time you have available, your specific age, your health status, and the specific types of brain changes that you might be seeking through the use of exercise. And I should also say that by learning how exercise impacts brain performance and brain health, you're also going to learn some of the incredible ways that your body communicates with your brain and your brain communicates with your body, not just during exercise, but all of the time. So today, you're going to learn a lot of practical tools, of course, about exercise, brain health, and longevity. It's based on research that is incredibly interesting, in some cases surprising, and in almost all cases actionable. As some of you may already

• 3:05Andrew D. Huberman?

  know, I have a book coming out this year, 2025, entitled Protocols: An Operating Manual for the Human Body. I'm super excited about the book. It includes protocols, that is actionable steps that anyone can take to improve their sleep, motivation, creativity, gut microbiome, nutrition, exercise, stress modulation, and much more. Now, the book was originally scheduled to be released in April of 2025. However, to make sure that the book reflects the latest scientific research, I've decided to expand on the yes, already finished version of the book to make sure that the protocols are as up to date as possible and reflect the most modern and best findings. So the new release date for protocols is going to be September of 2025. I do apologize

• 3:47Andrew D. Huberman?

  for the delay in release, but I assure you that I will make it worth your wait. To learn more about the book or to secure a copy by pre-sale, go to protocolsbook.com. There you'll find all the information about the book, as well as the various languages that the book will be translated into. Before we begin, I'd like to emphasize that this podcast is separate from my teaching and research roles at Stanford. It is, however, part of my desire and effort to bring zero cost to consumer information about science and science-related tools to the general public. In keeping with that theme, I'd like to thank the sponsors of today's podcast. Our first sponsor is BetterHelp. BetterHelp offers professional therapy with a licensed therapist carried out entirely online. Now, I've been doing weekly therapy for well over 30 years.

• 4:30Andrew D. Huberman?

  Therapy is an extremely important component to overall health. In fact, I consider doing regular therapy just as important as getting regular exercise. Now, there are essentially three things that great therapy provides. First, it provides a good rapport with somebody that you can really trust and talk to about any and all issues that concern you. Second of all, great therapy provides support in the form of emotional support, but also directed guidance, the do's and the not-to-do's. And third, expert therapy can help you arrive at useful insights that you would not have arrived at otherwise. Insights that allow you to do better, not just in your emotional life, in your relationship life, but also the relationship to yourself and your professional life and all sorts of career goals. With BetterHelp, they make it very easy to find an expert therapist with whom you can

• 5:12Andrew D. Huberman?

  really resonate with and provide you with these three benefits that I described. Also, because BetterHelp is carried out entirely online, it's very time-efficient and easy to fit into a busy schedule with no commuting to a therapist's office, or sitting in a waiting room, or looking for a parking spot. So if you'd like to try BetterHelp, go to betterhelp.com/huberman to get 10% off your first month. Again, that's betterhelp.com/huberman. Today's episode is also brought to us by Helix Sleep. Helix Sleep makes mattresses and pillows that are customized to your unique sleep needs. Now, I've spoken many times before on this and other podcasts about the fact that getting a great night's sleep is the foundation of mental health, physical health, and performance. Now, the mattress you sleep on makes a huge difference in the quality of sleep that you

• 5:57Andrew D. Huberman?

  get each night. How soft that mattress is, or how firm it is, how breathable it is, all play into your comfort and need to be tailored to your unique sleep needs. So if you go to the Helix website, you can take a brief two-minute quiz that asks you questions such as, do you sleep on your back, your side, or your stomach? Do you tend to run hot or cold during the night? Things of that sort. Maybe You know the answers to those questions? Maybe you don't. Either way, Helix will match you to the ideal mattress for you. For me, that turned out to be the Dusk mattress, D U S K. I started sleeping on a Dusk mattress about three and a half years ago, and it's been far and away the best sleep that I've ever had. So much so that when I travel to hotels and Airbnbs, I find I don't sleep as well. I can't wait to get back to my Dusk mattress. So if you'd like to try Helix, you can go to helixsleep.com/huberman.

• 6:40Andrew D. Huberman?

  Take that two-minute sleep quiz, and Helix will match you to a mattress that's customized for your unique sleep needs. Right now, Helix is giving up to 25% off all mattress orders. Again, that's helixsleep.com/huberman to get up to 25% off. Okay, let's talk about the relationship between exercise, brain health, and longevity, and performance. And let's just take a couple of minutes and really clearly define what we mean by exercise. Because most of us have a concept of what exercise is, but for sake of understanding the relationship between exercise and brain performance, most of the peer-reviewed studies focus on two general categories of exercise: either cardiovascular exercise or resistance training. Now, of course, cardiovascular exercise can be a very short-duration, high-intensity,

• 7:25Andrew D. Huberman?

  so getting heart rates up way, way, way up, or longer-duration, lower-intensity. Now, typically, the amount of time scales with that, so the shorter-intensity stuff tends to be quick bouts of either 30 seconds, 60 seconds, sometimes two-minute or even four-minute all-out effort with some period of rest afterwards, or longer duration: 20, 30, 45, or even 60 minutes of cardiovascular training at a more steady-state, lower-intensity. And I should mention that within the tens of thousands of studies that are out there exploring the relationship between exercise and brain health and longevity, you will mostly see studies focused on cardiovascular exercise. And most of those studies, early on, were focused on the longer-duration, lower-intensity stuff.

• 8:10Andrew D. Huberman?

  So typically, 30 to 60 minutes of lower intensity, yet still elevating the heart rate, exercise. Nowadays, there's more of a focus on the high-intensity interval training, and today we're even going to hear about some studies that involve very, very short bursts, so-called sprints of activity, as short as six seconds long, followed by a period of rest, repeated for a number of times, and exploring what the effect of that sort of, I should say, very, very short-intensity exercise is on immediate and long-term brain health and performance. Okay, so cardiovascular training of different durations and intensities. Involving different durations of rest are one category that we're going to talk about today. The other category of exercise we're going to talk about today is resistance training.

• 8:53Andrew D. Huberman?

  Now, most of the studies involving resistance training and their effects on the brain, both brain longevity and brain performance, focus on either compounds, so multi-joint movements. So think squats, deadlifts, bench press, shoulder press, dips, et cetera. But very often, and this is just a byproduct of how studies are done in the laboratory, very often, the exploration of the relationship between resistance training and brain health and longevity are single-joint isolation exercises, like a single-leg leg extension even. You might be thinking, wait, just one leg doing the leg extension? Yes. The reason for that, and I spoke to some of the scientists that do this sort of work,

• 9:33Andrew D. Huberman?

  is that when they have subjects do a, say, seated, single-leg leg extension as the form of resistance training, I know I and some of you are probably chuckling like, really? Of all the things you could select to see if it impacts brain health, you're gonna have people kick up one knee? Yep, you do that. Why? Well, most people can do that type of movement. It doesn't take any training, or it just takes a little bit of direction as to how to do it. So it can be done reasonably safely by many people, including people that are non-athletes, often older than 65 years old. Not that there aren't some very fit 65-year-olds, but just people who are older than 65 but don't have a lot of athletic background, can sit down in a chair, put the pin at the appropriate weight, and move their knee, or rather elevate their foot while seated in a chair, so-called "single-leg leg extension."

• 10:18Andrew D. Huberman?

  And also, it gives the benefit of the opposite leg within subject control for comparison in terms of strength increases. Okay, so, set aside any kind of, you know, like, eye rolls or chuckles that you might have about single-leg leg extensions as the total form of resistance training that's being explored, because, yes, those studies are still informative. In fact, they perhaps even identified the lower threshold for the amount of resistance training and type of resistance training that could benefit the brain. But we also see studies that involve compound exercises. So having people do free weight squats, or even weighted squats, or deadlifts, or, you know, bench press, dip, deadlift-type combinations. Again, when you look at the literature exploring exercise and brain health...

• 11:01Andrew D. Huberman?

  You're looking at studies that, in the best cases, are very tightly controlled. That typically means having people do them in the laboratory in a very specific way. Sometimes using untrained subjects, meaning when the subjects arrive at the study, they haven't done much exercise of that sort. Sometimes it's involving trained subjects. Both have their caveats, of course. But keep in mind that during today's discussion, I'm going to be pooling at many times across all these studies, exploring cardiovascular exercise of different duration and intensities, resistance training of different types, and sometimes different intensities as well. But where there is a specific piece of knowledge that can be gleaned from understanding the exact type of exercise that was done and a specific type of brain change, especially

• 11:46Andrew D. Huberman?

  in cases where it's been shown to be especially beneficial, I will be sure to highlight that. So, as we proceed in today's discussion, keep in mind, exercise is many things, two general categories. Most of the studies focus on high-intensity or low-intensity cardio. Most of the studies involve either single joint isolation exercises, sometimes even single joint, single-leg isolation exercises, or compound exercises. And keep in mind that most of the studies exploring the relationship between exercise and brain health and performance are done to explore two types of changes. Either what are called acute changes, meaning immediate changes, so they have people do the exercise, and then they have them take a cognitive test, or some other form of test

• 12:30Andrew D. Huberman?

  that analyzes brain health and performance. Or they look at chronic effects, which are, what are the changes in brain performance and health over long periods of time, meaning having people do a particular type of exercise anywhere from two to four times per week, although typically it's three times per week, and doing that for anywhere from four weeks to six months. Again, all of this relates to the practical aspects of running controlled studies in the laboratory. So if by now you're thinking, "This is really complicated." How is it that we're supposed to tease out the best things to do, given this huge ball of barbed wire of different types of studies, variables, et cetera? Well, I assure you, we are going to make this very clear and very actionable. And the thing to keep in mind is that fortunately, most all of the studies, yes, most all of

• 13:14Andrew D. Huberman?

  the studies that have explored the relationship between exercise, brain health, and longevity and performance, find positive effects. Now, for some of you who are skeptics, you might be thinking, "Well, great, so you can do any form of exercise?" Well, in some sense, yes. I'll actually tell you this right off the bat. There are good data showing that if people do six-second sprints, max all-out sprints, on a stationary bicycle, followed by one-minute rest, and repeat that six times, you see significant acute effects on brain performance. So, the brain performance could be a memory task, sometimes it is a memory task, it could be what's called a stroop task, which is a cognitive flexibility task, where you have to distinguish between the colors that words are written in

• 13:59Andrew D. Huberman?

  and the content of the words, okay, so-called stroop task, I've talked about this on previous podcasts, I'll talk about it a little bit more later. Regardless of the cognitive test that's used, that very short duration, high-intensity training increases performance significantly. As well, 20 or 30 minutes of so-called steady-state cardio, you know, figuring out how fast you can run, or row, or swim, or stationary bike, for 20 to 30 minutes at a steady state, and then you analyze people's cognitive performance on a memory task, can be a working memory task, so remembering a short string of numbers, or it could be math problems, it could be the stroop task, any number of different tasks reveal the same thing, which is that the longer

• 14:38Andrew D. Huberman?

  duration, lower intensity cardio also significantly improves performance. Now, does that mean that you can do six rounds of six seconds of sprinting with a minute in between, or 20 minutes of cardiovascular exercise and get the same effect on brain performance? Well, if you're just looking at overall improvements in performance, so for instance, the percentage of information that you learn, if you do or you don't do the exercise, or if you compare those two forms of exercise that I just mentioned, in that sense, yes, it really doesn't make a difference, which may have you scratching your head, but in a few moments, I'll explain why that is. On the other hand, different forms of exercise, of course, impact our bodily health differently. Higher-intensity, shorter-duration exercise, of course, impacts things like VO2 max, and

• 15:22Andrew D. Huberman?

  which circulating hormones and neuromodulators are going to be present very differently than longer-duration, lower-intensity exercise. So too, if you have people do single-joint isolation resistance training exercises, like a single-leg leg extension, or both-legs leg extension, versus 10 sets of 10 in a squat exercise, you're going to see very different, specific adaptations at the physical level, at the bodily level. But in every case...

• 15:50Andrew D. Huberman?

  Where you explore the acute, the immediate changes that occur in brain output and function after people do that sort of exercise, you're going to see significant increases. When one does physical exercise, short duration, high intensity cardio, or higher intensity resistance training, single joint training, compound training, single joint isolation exercises, compound exercises, one sees these increases in brain performance, at least acutely in the immediate stage after the training. So we have to ask ourselves, why is it, how is it that all these different forms of exercise are positively impacting brain performance?

• 16:29Andrew D. Huberman?

  And the answer is very simple and fortunately gives us tremendous leverage over our exercise and how to impact our brain health. And the answer is arousal. However, the answer isn't entirely arousal, meaning not all of the positive effects of exercise on brain health, longevity and performance can be explained by arousal. But when I step back from the literature, again, an enormous literature, tens of thousands of peer reviewed papers, many of which are done exceptionally well, by the way, as well as meta-analyses and reviews, I think it's fair to say that probably 60 to 70% of the effects of exercise on brain health, performance and longevity can be explained by the specific

• 17:10Andrew D. Huberman?

  shifts in our physiology, both bodily physiology and directly within the brain's physiology during those bouts of exercise, which is this increase in so-called autonomic arousal, which occurs during the exercise, but also extends into a window after the exercise is completed. So we have to talk about this relationship between exercise, arousal and acute brain performance, meaning the improvements in brain performance that happen immediately after the exercise. And then we'll shift our focus to the effects of exercise that occur more chronically. That is, the effects of exercise on brain health and performance that occur in the hours, days, weeks and years after we exercise, even if we are continuing to exercise every

• 17:53Andrew D. Huberman?

  day or three times a week, or whatever the frequency might be. But this issue of arousal is extremely important, and I assure you, it's not trivial. In fact, it will help you understand a number of things in the domains of deliberate cold exposure, stress, trauma, and most importantly, for today's discussion, it will help you design an exercise program that's geared towards giving you the maximum bodily health effects and the maximum brain health effects. Okay, in order to understand the relationship between exercise, arousal, and learning, we have to really clarify the relationship between arousal and learning. That's going to set the stage for pretty much everything else we're going to talk about for the next 10 minutes or so. And it's oh so cool.

• 18:34Andrew D. Huberman?

  It also gives me the opportunity to review a paper that I've long loved, which comes from Larry Cahill's group down at UC Irvine entitled "Enhanced Memory Consolidation with Post-Learning Stress: Interaction with the Degree of Arousal at Encoding." This is just one of several papers from the Cahill Group, which essentially identified the following: There are a couple of different ways you can increase so-called autonomic arousal, or levels of alertness. Sometimes it's called stress, but autonomic arousal is simply an increase in the amount of activity in the so-called sympathetic arm of the autonomic nervous system, which is nerd speak for: more alert, more aroused, wide-eyed, ready to move, higher heart rate, higher blood pressure, more alertness. This is a great state to be in for learning material, provided it's not too much alertness,

• 19:18Andrew D. Huberman?

  too much arousal. Turns out, this paper shows, it's also a great state to be in after you've been exposed to material that you want to learn. And it's also the case that in this paper, and in many, many other papers from this and other laboratories, that you can increase levels of autonomic arousal by having people put their arm into ice water for one to three minutes, the so-called cold presser test. It's a very commonly used standard test. This paper and many other papers show that it leads to very rapid and significant increases in circulating levels of cortisol, which, yes, sometimes is called a stress hormone, but it's really just a hormone involved in the stress response, but does a bunch of other things, too. So they use that as a tool.

• 20:00Andrew D. Huberman?

  After people have been exposed to certain types of information to ask, "Does elevation in cortisol, aka autonomic arousal, improve one's ability to remember information?" And the answer is yes. This study shows that. Several other studies from the Cahill and other laboratories show that. Sometimes those studies use people putting their arm into ice cold water. Other times, they'll inject them with a drug that increases adrenaline, also called epinephrine, sometimes also increases cortisol. The point being that elevations in autonomic arousal after one is exposed to information increases one's memory for that information and one's memory for the details of that information. Now,

• 20:43Andrew D. Huberman?

  in this particular study, they compared emotionally laden versus non emotionally laden information and a bunch of other details, which are interesting if you choose to peruse this study. But I should mention that other studies from this and other laboratories have shown time and time again, increases in autonomic arousal measured by increases in cortisol or adrenaline, also called epinephrine, or norepinephrine, which is the sort of analog within the brain, that consistently leads to better memory for information that one has been exposed to, better memory for the details of that information, and oftentimes, better ability to work with that information, to come up with new ideas with that information, or to think logically about that information in new ways. In other words, increasing autonomic

• 21:25Andrew D. Huberman?

  arousal improves learning and memory. Now, it's also very important to understand that that increase in autonomic arousal can improve learning and memory if the autonomic arousal occurs after the exposure to the material. Most people find that a bit surprising. I certainly did when I first read this paper. It makes sense if you start to think about the persistence of memories for things like traumas or bad events, right? Bad event happens, and there's this big spike in cortisol and adrenaline, and those memories are hard to eradicate. They're certainly hard to remove the emotional content from. And if you think about it, in those instances, the event happens and then comes the big increase in cortisol and adrenaline. So that maps very well onto the study that I'm describing here. In addition, however, lots of studies have shown that increasing autonomic arousal, as measured

• 22:10Andrew D. Huberman?

  by increases in adrenaline, or cortisol, or both, or any number of different measures of autonomic arousal.

• 22:18Andrew D. Huberman?

  That occurs during the exposure to the new material. Okay, so this isn't trauma. This is like new math material, new history material, new music material, new motor skill material that you're trying to learn. Increases in autonomic arousal that occur as you're trying to so-called encode the information. You're being exposed to that new information also significantly improve learning. And it's always through increases in arousal. In other words, whether or not you're measuring cortisol, adrenaline, heart rate, blood pressure, galvanic skin response, how wide someone's pupils are, or small someone's pupils are, or any combination of those things, or any other measures of autonomic arousal, the

• 22:59Andrew D. Huberman?

  consistent takeaway is increases in arousal during or after, in particular after, trying to learn a certain material is going to improve significantly the amount of material that one learns, the details of that material, and the persistence of that learning over time. I'd like to take a quick break and acknowledge our sponsor, AG1. AG1 is a vitamin, mineral, probiotic drink that also includes prebiotics and adaptogens. As somebody who's been involved in research science for almost three decades and in health and fitness for equally as long, I'm constantly looking for the best tools to improve my mental health, physical health, and performance. I discovered AG1 way back in 2012, long before I ever had a podcast or even knew what a

• 23:43Andrew D. Huberman?

  podcast was, and I've been taking it every day since. I find that AG1 greatly improves all aspects of my health. I simply feel much better when I take it. AG1 uses the highest quality ingredients in the right combinations, and they're constantly improving their formulas without increasing the cost. In fact, AG1 just launched their latest formula upgrade. This new formula is based on exciting new research on the effects of probiotics on the gut microbiome, and now includes several clinically studied probiotic strains shown to support both digestive health and immune system health, as well as to improve bowel regularity and to reduce bloating. Whenever I'm asked if I could take just one supplement, what would that supplement be? I always say AG1. If you'd like to try AG1, you can go to drinkag1.com/

• 24:27Andrew D. Huberman?

  Huberman to claim a special offer for this month only, January 2025. AG1 is giving away 10 free travel packs and a year's supply of vitamin D3 K2. Again, go to drinkag1.com/huberman to claim the 10 free travel packs and a year's supply of vitamin D3 K2. Today's episode is also brought to us by David. David makes a protein bar unlike any other. It has 28 grams of protein, only 150 calories and zero grams of sugar. That's right, 28 grams of protein and 75% of its calories come from protein. These bars from David also taste amazing. My favorite flavor is chocolate chip cookie dough. But then again, I also like the chocolate fudge flavored one, and I also like the cake flavored one. Basically, I like all the flavors.

• 25:11Andrew D. Huberman?

  They're incredibly delicious. For me personally, I strive to eat mostly whole foods. However, when I'm in a rush, or I'm away from home, or I'm just looking for a quick afternoon snack, I often find that I'm looking for a high quality protein source. With David, I'm able to get 28 grams of protein with the calories of a snack, which makes it very easy to hit my protein goals of one gram of protein per pound of body weight each day. And it allows me to do that without taking in excess calories. I typically eat a David bar in the early afternoon or even mid afternoon if I want to bridge that gap between lunch and dinner. I like that it's a little bit sweet, so it tastes like a tasty snack, but it's also given me that 28 grams of very high quality protein with just 150 calories. If you would like to try David, you can go to davidprotein.com/huberman.

• 25:56Andrew D. Huberman?

  Again, the link is davidprotein.com/huberman. Okay, so now we've established that elevated levels of autonomic arousal either during or after, and indeed also before a bout of learning, the so-called encoding phase of learning, when we're exposed to the new material that we want to learn and remember, are all beneficial. This is wonderful news. When we look out on the whole of the literature, On the relationship between exercise and brain health and performance, we see studies that incorporate exercise either before or after a bout of learning. And we also find studies, believe it or not, that combine exercise with learning in real time, literally, exposing people to new material that they're expected to learn or trying to

• 26:39Andrew D. Huberman?

  learn while they're walking on a treadmill, or running on a treadmill, or cycling, or rowing. Yes, those studies have also been done, although for practical reasons, they're not as numerous as the studies exploring the relationship between exercise and learning, where the exercise is done before or after the bout of learning. Okay, so what this means is wonderful. What this means is that if you want to use exercise not just for enhancing your bodily health, but also for brain health and performance, you can do that exercise before, during, or after bouts of learning. That allows you to look at the constraints of your life. For instance, are you one of these people that can get up at 5:00 or 6:00 or 7:00 a.m. and exercise before everyone else gets up, or before your workday starts, or your school day starts, do a round of

• 27:24Andrew D. Huberman?

  exercise, and then get into your bouts of learning, whatever that material may be? Or are you somebody who has to dive into the workday, school day, family obligations, et cetera, in which case you might only be able to exercise later in the day, but you're probably still somebody who would like to enhance their brain health and performance? So in that case, you might organize the thing that you're trying to learn, the encoding, or the exposure to the thing that you're trying to learn, either in written forms, you're reading, or you're listening to it, or you're attending a class, or classes, and then exercising after you're exposed to that material, in order to get that elevated levels of arousal, not unlike the arrangement of the studies that I was talking about earlier, which used the ice exposure in order to generate increases in arousal, and thereby to improve learning and memory.

• 28:08Andrew D. Huberman?

  So in the show note captions for this episode, we've batched a number of different references that have explored the relationship between exercise and cognitive performance. And across those studies, and the ones that are referenced therein, you'll find studies where the exercise bout was done before, where the exercise bout was done during, where the exercise bout was done after a round of learning, or encoding of information. And I should mention that different studies focus on different cognitive tasks. So exercise and the arousal associated with exercise has been shown to acutely improve Recall, so just raw recall of material, the details in material. It's been shown to improve cognitive flexibility through things like the stroop task.

• 28:50Andrew D. Huberman?

  And so in a very convenient way, exercise has been shown to acutely improve performance on all those sorts of brain and memory tasks, which is greatly reassuring to all of us because what it means is that it probably doesn't matter so much when you do your exercise or what it is that you're trying to learn. It's going to be beneficial as long as the thing that you're trying to learn and the exercise are positioned fairly closely in time. Now, the one caveat to that is that several studies have explored the relationship between short-duration, high-intensity interval training and cognitive performance, in particular, executive function, that cognitive prefrontal flexibility that we were talking about a few moments ago.

• 29:30Andrew D. Huberman?

  And on the whole, all of those studies point to improvements in executive control and function. So that context-dependent switching of knowledge and your ability to think about things in a very agile way, if you will, if people did a high-intensity interval training session just before they do that bout of cognitive flexibility learning. However, several studies have also looked at the effect of repeated bouts of high-intensity interval training, and in some cases, looking at the mechanisms by which high-intensity interval training improved cognitive performance. And the basic takeaway is the following. And again, I'll provide references to these in the show note captions. That high-intensity interval training done before, or believe it or not, even during cognitive flexibility tasks,

• 30:15Andrew D. Huberman?

  a couple of studies have actually explored that, significantly improves performance on those tasks. Again, we believe this is likely through enhanced levels of arousal, although some data also point to the fact that it's also likely through enhanced cerebral blood flow, simply more blood being delivered to the brain during or in particular after high-intensity interval training. More blood, more fuel, and other molecules being delivered to the brain during a cognitive task or cognitive flexibility task makes sense why that would improve cognitive function. And yet, when studies have explored the consequence of doing multiple high-intensity interval training sessions, and when I say "high-intensity," I mean "high-intensity." These are studies where lactate is elevated, we'll talk more about lactate in a few minutes,

• 30:59Andrew D. Huberman?

  where typically people's heart rate is either close to or at their maximum heart rate for some period of time, either 30 seconds, 60 seconds, 2 minutes, or in some cases, people are pushing really, really hard for 4 minutes, then resting for 4 minutes, then pushing really hard for 4 minutes, then resting for 4 minutes, 4 times over. The so-called 4x4 program that I know a number of you have heard about, if you haven't, it's very intense, so you can imagine, all out for 4 minutes, then rest, all out for 4 minutes, then rest. Doing that several times in a day, okay, so 2 bouts of 4x4, or 2 high-intensity interval training sessions of any kind, has been shown to diminish cognitive performance if the cognitive task comes after the second high-intensity interval training session. Now, for most of us, including me, that makes sense.

• 31:44Andrew D. Huberman?

  You think, "Well, they're tired, you know, people aren't able to focus as much because they're devoting all this energy to their exercise." And indeed, that's true, although the mechanism is interesting. The studies that have looked at this have actually found that cerebral blood flow during the 2 bouts of high-intensity interval training are more or less equal. So it's not that the first session necessarily precludes high performance in the high-intensity interval training session in the second session, but then when you go on to try and do a cognitive task that's demanding and also requires elevated levels of cerebral blood flow, you find that performance drops, and this is correlated with reductions in cerebral blood flow that come from doing too much high-intensity interval training. Now, I have to acknowledge that most people aren't doing multiple high-intensity interval

• 32:29Andrew D. Huberman?

  training sessions per day, but this is a reminder, an important reminder in fact, that if you're using exercise to try and improve brain health and function, or even if you're just somebody who's exercising but is also expected to use their brain to learn things throughout the day, as most of us are, and to attend to things throughout the day, you need to be cautious about not overdoing the high-intensity interval training sessions. This is also true for resistance training. You need to be aware that very high-intensity exercise, yes, increases cerebral blood flow, and the delivery of all these fuels and other compounds to your brain during the exercise... If you do that correctly and you don't overdo it, you can capture some of that wave of blood flow, fuel, et cetera, as you enter the learning session. But if you quote unquote, "overdo it",

• 33:13Andrew D. Huberman?

  then you're going to arrive to that bout of learning with reduced cerebral blood flow, and you're going to be in a state that it's very difficult to focus and learn new information. So there is such a thing as too much arousal from exercise that leads to troughs in arousal that diminish cognitive performance and learning. Now, all of this is focused, of course, on the relationship between exercise and brain function at the acute level, the immediate level. It's fair to say that all high intensity exercise and resistance training is going to support brain function in the chronic sense, in the long-term sense. In fact, the literature points to that. And once again, I've batched the references for this episode so that they're grouped together according to the specific topics and timestamps. And the two studies that I recommend you look at, if you're interested in this relationship

• 33:57Andrew D. Huberman?

  between high intensity training and cognitive function, in particular, executive function, that cognitive flexibility I was talking about earlier, such as in the Stroop task. There's a wonderful article entitled, "Executive Function After Exhaustive Exercise", that's one to look at. And the other one, which I think is really nice, and therefore I've placed there, really points to the way that a single bout of exercise can acutely improve brain function, in particular, executive function. And the title of that paper, not surprisingly, is, "A Single Bout of Resistance Exercise Can Enhance Episodic Memory Performance." Here's a fun one. As I continue to hammer on this thesis that so many of the positive effects of exercise on brain health and performance, at least in the acute sense, immediately after the exercise,

• 34:41Andrew D. Huberman?

  in some cases during the exercise, are due to arousal. Well, then it should make sense why things like so-called "exercise snacks", you know, this idea that, you know, throughout the day, you, you know, suddenly do 25 quick jumping jacks, or you, you know, you jump up and down five times, or you do 20 air squats. You know, we've heard about exercise snacks in different contexts, such as, you know, adjusting blood glucose levels. You hear a lot about that, you know, after meals, you know, take a walk, or do some jumping jacks really quick, or, you know, do 20 air squats throughout the day. And people talk about the sort of outsized positive effects of the... Well, check this out. When it comes to high intensity interval training and positive effects on cognitive performance, there's a study entitled "The Influence of Acute Sprint Interval Training on Cognitive Performance in Healthy Younger Adults." And this study

• 35:24Andrew D. Huberman?

  has people do six-second all-out efforts. You heard that right. Six seconds. Okay? So, six, six seconds. It always is tricky. They always use the same numbers. The, you know, four by four by four. Okay. Six, yes, the number six. Six-second all-out efforts, sprinting on basically a stationary bike, and then a period of rest of one minute between those six-second all-out efforts. And they see a significant improvement in cognitive performance. So, yes, it's true that you can do very brief, very intense bouts of exercise. I mean, just think about six seconds of sprinting, one minute of just cruiser rest,

• 36:07Andrew D. Huberman?

  six seconds, and then just repeat for six sprints, total of six seconds each, and experience an enhancement. That is an acute or immediate enhancement in cognitive function. And I can imagine no other mechanistic explanation for that, aside from increased levels of autonomic arousal. Any other mechanism that you could envision, you know, IGF-1, Irisyn, BDNF, things that we'll talk about in a few minutes, yes, those might be deployed as well. But in terms of seeing something so brief, having such a fast action on cognitive performance, and given what you now know about the relationship between arousal, focus, and cognitive performance, I'd be willing to stake, let's say, six of my 10 fingers

• 36:52Andrew D. Huberman?

  on the idea that it's all due to enhanced autonomic arousal. Okay, let's talk for a few minutes about the mechanisms by which exercise improves brain health and performance. And I realize when I say mechanisms, some of you may say, "Okay, well, I just want to know what to do. I don't need to hear about the mechanisms." But in this case, understanding just a little bit about the pathways by which exercise impacts the brain can give you a ton of leverage in designing the best exercise schedule for your brain health and performance, and frankly, for your exercise schedule generally, to generate things like fat loss, improvements in strength, hypertrophy, endurance, and so on. In fact, let's do this mental experiment together. If we were to ask ourselves, how is it that exercise improves brain health and

• 37:37Andrew D. Huberman?

  performance? Based on what you know now, you'd probably say, well, it increases arousal, the catecholamines, so dopamine, epinephrine, norepinephrine. It probably increases heart rate, so more blood pumping to the brain, and so on and so forth. And you would be correct about all of that. But let's just think a little bit more deeply about how exercise actually impacts the brain in the short and long term, and ask ourselves, what are the different physical pathways? What are the different chemical pathways by which the movement of our body changes the way that our brain works in the short and long term? So if we were to draw a stick figure of a human and orient ourselves to the different locations or organs in the body that contain potential sources of information for the

• 38:20Andrew D. Huberman?

  brain, one place that we could start would be, of course, the heart. When you do cardiovascular exercise of any kind, intense or not so intense, short or long, your heart rate increases, your blood pressure increases. Likewise, if you do resistance training, there will be heart rate increases. Those heart rate increases will come down between sets, but your heart rate tends to increase when you exercise. That's sort of a duh. Well, when your heart rate increases, there's actually both increased blood flow to the brain and the delivery of all the things that that blood carries, but there are also neural pathways that carry signals about that heart rate, about those blood pressure changes, to the brain in order to increase our levels of alertness and focus that we can leverage toward learning.

• 39:03Andrew D. Huberman?

  So the first location in the body that we know can communicate with the brain is the heart. When our heart beats faster, that's communicated to our autonomic nervous system, which resides in a number of different brain areas. In fact, it's a network of brain areas that act in concert to create what we call autonomic arousal. We also have another pathway that goes back from the brain to the heart and other organs that we call the vagus nerve, which is a two-directional pathway, you know, up from the body to the brain and from the brain back to the body. We're going to talk a lot about the vagus. In fact, let's talk about the vagus now. When we exercise, we release adrenaline, which is also called epinephrine, from our adrenal glands, which are small glands that reside atop both of our kidneys.

• 39:45Andrew D. Huberman?

  That adrenaline, or epinephrine, as it's also called, does many things in our body. It's responsible for increasing our heart rate further. It's responsible for a number of effects on the so-called endothelial cells that make up the vessels and capillaries. And it has impacts on the neurons in our body that create all sorts of changes in the way that blood flows, how fast it flows, and so on and so forth. Now, here's a key thing to understand. Adrenaline, epinephrine, does not cross the blood-brain barrier. So the adrenaline from our adrenals doesn't actually get into the brain to stimulate elevated levels of alertness. Rather, it acts on receptors on the vagus nerve. Again, the vagus nerve communicates with the brain, and also in the vagus nerve, certain brain areas communicate with the body.

• 40:27Andrew D. Huberman?

  So adrenaline has a lot of effects within the body, but when it's released, it also acts on so-called adrenergic receptors on the vagus nerve. Then the vagus nerve is activated in a way that stimulates the activity of a brain area, because remember, the vagus goes from the body into the brain, stimulates the so-called N S T, and because neuroanatomists like to argue about naming, sometimes it'll also be called the N T S, the nucleus of the solitary tract, or the nucleus tractus soliteris. Super annoying, I know. Forget the acronym, unless you want to know that it's sometimes N S T and sometimes it's N T S. Don't ask me why neuroanatomists do this. In any case, the N S T can then communicate with a really important brain area, whose name you should remember, which is the locus ceruleus.

• 41:11Andrew D. Huberman?

  The locus ceruleus contains neurons that release, among other things, norepinephrine, which is similar in action to epinephrine, but different. Neurons in the locus ceruleus send those little wires that we call axons into the brain in a very widespread manner. It's almost as if they're positioned to sprinkler the brain with a neurochemical, and that neurochemical is norepinephrine. They also have the capacity to release other neurochemicals, but right now, we're concentrating on norepinephrine. When norepinephrine is released from the locus ceruleus, it has this tendency to elevate the levels of activity in other brain areas, through this sort of sprinklering-like mechanism. What that means is that other areas of the brain, such as your prefrontal cortex, such as your hippocampus, such as different areas of the hypothalamus, and indeed, lots of brain

• 41:55Andrew D. Huberman?

  circuits, all have a greater capacity to be engaged. This is what we're talking about when we talk about autonomic arousal. Release of adrenaline from the adrenals that has action within the body, elevated heart rate, blood pressure, et cetera. And then adrenaline also from the adrenals to the vagus, from the vagus to the N S T, N S T to locus ceruleus, and then locus ceruleus sprinklers the brain with this norepinephrine, raising the levels of baseline activity in all those brain areas and making them more likely to be engaged by things that we're trying to attend to, more likely to engage, say, the neurons of the prefrontal cortex that can learn context-dependent strategy switching, such as in a stroop task, or when we're trying to attend to information and we go, okay, here's something important, I need to pay attention to this. We're able to do

• 42:40Andrew D. Huberman?

  that because of that elevated level of norepinephrine. It facilitates, it's permissive for elevating our levels of attention and focus. It's also permissive for our hippocampus to encode new memories and for a bunch of other brain areas to do their thing, so to speak. So knowing these mechanisms is actually worthwhile. If you've ever heard that exercise can give you energy, this is the basis of that statement, right? Many people, in fact, myself for many years, thought, okay, I definitely have to sleep well in order to have energy and focus. That's absolutely true, still true, will always be true. I should maybe have some caffeine, be hydrated, you know, well nourished, all this stuff, in order to have the energy to exercise. But it's also true that exercise gives us energy, and this is how it gives

• 43:22Andrew D. Huberman?

  us energy. When we move our body, the adrenals release adrenaline and the adrenaline acts through two different so-called parallel pathways within the body, but again, it doesn't cross the blood-brain barrier. So then there's a series of what we call signaling relays or circuit relays up to the locus ceruleus, and then a sort of analog, it's different, but an analog to epinephrine, norepinephrine, is released within the brain, and low and behold, we have elevated levels of both bodily energy and brain energy and focus that we can devote to that exercise, but also to the learning that comes after that exercise, which explains pretty much everything that we've talked about up until now during the course of this podcast. So the next time you're feeling a little tired and you don't want to work out, remember, exercise gives you energy through the pathways

• 44:07Andrew D. Huberman?

  that I just described. Now, anytime I talk about the adrenals, people start talking about adrenal burnout. They say, oh, you burn out your adrenals. You know, there are these crazy theories that you'll hear out there, you know, coffee burns out your adrenals. Not true. You'll hear that if you exercise too much, it might burn out your energy or your adrenals. Look, you have enough capacity within your adrenals to survive. Relatively long famines to survive long bouts of challenge, stress of many, many different kinds, short challenges and so on. You're not going to burn out your adrenals. There is something called adrenal insufficiency syndrome, which is a real syndrome. There are diseases of the adrenals, but that's not what we're referring to here. You have plenty of adrenaline in your adrenals that you can deploy through movement, through

• 44:51Andrew D. Huberman?

  exercise, to get the elevation and arousal, attention and so forth that we've been talking about. In fact, there's a set of biological pathways that were just recently discovered that will allow you to understand how to use movement in order to engage your adrenals so that then those adrenals can release adrenaline, impact your vagus, impact the organs of your body, the locus ceruleus, and elevate your levels of attention and focus. And a lot of the core components of these pathways are highlighted in a paper that I absolutely love, another paper I absolutely love. This is from Peter Strick's laboratory at University of Pittsburgh, which is entitled "The Mind-Body Problem: Circuits That Link the Cerebral Cortex to the Adrenal Medulla." The adrenal medulla are those adrenals that I've been referring to in the body.

• 45:35Andrew D. Huberman?

  And the question that Peter Strick and colleagues asked was, how is it that movement actually gets the adrenals to release adrenaline? Like, what's the signal? Does it come from the muscles? Does it come from, you know, the skeleton? It's perfectly reasonable to assume that there are signals that come from the muscles and from the skeleton that cause the adrenals to release adrenaline when we exercise. But what Strick and colleagues did was actually super clever. They took some new tools that had just become available. These are tools that allow the tracing of neural circuits from organs in the body all the way back up to the brain, or from one brain structure to another brain structure, and then to yet another brain structure. We don't have time to go into all the technical details, but this is a technique that perhaps I'll talk about on a future podcast.

• 46:19Andrew D. Huberman?

  It's one that my laboratory used for a number of years to trace other neural pathways. What they discovered is that there are essentially three categories of brain areas, all of which communicate with the adrenals and can cause them to release adrenaline to create this elevation and arousal and attention. Those three brain areas include areas of the brain that are involved in thinking, what we call cognition, areas of the brain that are related to what are called affective states, which is just kind of a more general category that includes emotions. Okay, if you saw the Huberman Lab podcast episode that I did with Lisa Feldman Barrett, she explains beautifully the distinction between affective states and emotions. But these are brain areas that basically relate to what we are feeling, or how we're perceiving

• 47:03Andrew D. Huberman?

  our environment and how we're reacting to it, these sorts of things. And then there's a third category of brain areas that most robustly communicates with the adrenals. And these are a collection of brain areas that are all involved with movement of particular areas of our body. These areas are broadly referred to as the motor network. So these are areas of the so-called cerebral cortex, which are in the outer portion of the brain. And they send these wires down the spinal cord. There's a little relay in the spinal cord. It's called the IML. If you're interested in the anatomical details, I'll put the link to this paper in the show note captions. In any case, these brain areas that are involved in motor movement, send axons, those wires, down to the spinal cord. Then from the spinal

• 47:46Andrew D. Huberman?

  cord, they send a relay out via what's called the cholinergic preganglionic neurons. Basically, what ends up happening is that acetylcholine, which is a neuromodulator, is released from these neurons that originate in the spinal cord, onto the adrenal medulla, and then the adrenal medulla, the so-called adrenals, same thing, adrenal medulla, adrenals, releases adrenaline. That creates these effects in the body on the heart, the muscles and other tissues. And then, as described before, that adrenaline also acts on the vagus, the vagus up to the N S T, locus rulius, and we have this elevation in alertness. So this paper, and papers that came subsequent to it, really explain how it is that the movement of our

• 48:27Andrew D. Huberman?

  body, AKA, exercise, allows us to have this elevation in arousal and alertness. It's a loop, okay? The adrenals release adrenaline. They do these things by these two parallel pathways I've been talking about. But Your decision to engage these motor areas, to move particular areas of your body, is what deploys that adrenaline. Now, you might be thinking, "Well, duh. Okay, when I exercise, there's adrenaline release. In order to exercise, I need to move my body, and these brain areas control the movement of my body." But it's not a duh. It's actually very profound because it turns out that the specific brain areas that best activate the adrenals are the brain areas that control the muscles closest to the midline, the core musculature, and the brain areas that are involved

• 49:12Andrew D. Huberman?

  in generating the sorts of movements that we would call "compound movements", at least in the context of resistance training, or that are responsible for moving multiple joints at the same time. So what this means in the practical sense is if you are feeling sluggish, you want energy, or you're simply exercising, both for bodily effects and for brain effects, you need the deployment of adrenaline, of epinephrine. You need the deployment of norepinephrine in the brain. And by the way, anytime you have a deployment of norepinephrine in the brain, almost always, there's a coordinated action of release of dopamine, which most people have heard of by now. Dopamine is involved in motivation, as well as movement, et cetera. So the simple takeaway here is if you want to get the arousal

• 49:56Andrew D. Huberman?

  that comes from exercise in order to use that arousal, to leverage it towards better cognition, brain health, et cetera, the key thing is to make sure that you're doing exercises that are compound exercises, so that these would be the movements. You can look these up. Just say "compound exercises", you can put that anywhere, and you'll see that that includes things like squats, deadlifts, you know, bench presses, dips, pull-ups, rows. And yes, of course, you want to train your whole body so that you have, you know, symmetry of a function, of strength, and you want to offset any injuries and things of that sort. There are aesthetic reasons, perhaps. But the idea here is if you want energy from exercise, you want focus, you need the deployment of the neurochemicals that we've been discussing, most notably epinephrine and norepinephrine.

• 50:38Andrew D. Huberman?

  And through the identification of this motor network, as well as the affective and cognitive networks that converge on this area of the spinal cord and then send communication to the adrenal medulla, you can essentially control the levels of arousal that your body and brain produces. So in describing this, my hope is that you'll no longer think about exercise as just elevating your heart rate, or you no longer think about exercise just as moving your body, but rather that the movement of your body is creating specific neurochemical outcomes, both in the body and the brain, that create the arousal that initiates the improvements in focus and attention that allow you to learn better and that contribute generally to brain health and longevity. And of course, you aficionados out there

• 51:22Andrew D. Huberman?

  will remind me, I'm sure, but I'm gonna beat you to the punch here. Yes, your hypothalamus is also talking to your pituitary, which releases certain chemicals into your bloodstream, which also go to your adrenals to cause your adrenals to deploy both adrenaline, epinephrine, as well as cortisol. That pathway is still intact, okay, but that's a slightly slower pathway. Here I'm focusing on the neural pathways, some of which have only recently been discovered in the last five or 10 years, that work very, very fast to generate the sorts of arousal that are relevant to brain function and brain longevity. Okay? Nothing has changed in terms of the old story about how the brain impacts the adrenals. That's all still there, but here we're into the modern stuff. And by the way, for those of

• 52:06Andrew D. Huberman?

  you that are interested in things like psychosomatic disorders, trauma, and how trauma can quote-unquote "be stored" in the body, and it's not so much stored in the body, but how it can impact the body, and then how the body itself can impact the brain. This paper has also been used as support for the idea that indeed, those affective areas, those emotional areas, those cognitive areas, have a route by which they can communicate with the adrenal medulla to cause the release of adrenaline when we have specific thoughts. It was always known that if we have specific thoughts, it can quote-unquote "stress us out," our heart rate can go up, etc. This paper also provides a reasonable anatomical substrate for that phenomenon. You know, I never want to make too much of any one single paper or finding, but I will say that after I read that paper from Stricken colleagues, and through some

• 52:51Andrew D. Huberman?

  of the subsequent discussions about that paper that I overheard at meetings and so forth, it really made me think differently about exercise. And now, anytime that I'm feeling tired, provided that I'm not chronically sleep deprived or something of that sort, I remind myself that if I start moving my body, in particular if I engage core muscles, that was one of the key findings in that paper, that the areas of the brain that control the core muscles, as well as do compound movements, I move multiple joints, I start warming up in a way that includes some, maybe even just air squats, or some running in place, or jumping jacks, things of that sort, that the increase in energy that I'm perceiving is real. It's based on the same neurochemical outputs that would occur had I gone into

• 53:32Andrew D. Huberman?

  the gym, or to the run, or whatever workout with tons of energy, it would just have increased the level of adrenaline further. So this idea that we can actually control our body with our mind, and to some extent, our mind with our body, that's absolutely true. And this is one of the tools that I find particularly useful anytime I want to overcome that wall of resistance to not doing the physical exercise that I know I and basically all of us should be doing. I'd like to take a quick break and thank one of our sponsors, Function. I recently became a Function member after searching for the most comprehensive approach to lab testing. While I've long been a fan of blood testing, I really wanted to find a more in-depth program for analyzing blood, urine, and saliva to get a full picture of my heart health,

• 54:15Andrew D. Huberman?

  my hormone status, my immune system regulation, my metabolic function, my vitamin and mineral status, and other critical areas of my overall health and vitality. Function not only provides testing of over 100 biomarkers key to physical and mental health, but it also analyzes these results and provides insights from top doctors on your results. For example, in one of my first tests with Function, I learned that I had two high levels of mercury in my blood. This was totally surprising to me, I had no idea prior to taking the test. Function not only helped me detect this, but offered medical doctor-informed insights on how to best reduce those mercury levels, which included limiting my tuna consumption, because I'd been eating a lot of tuna, while also making an effort

• 54:57Andrew D. Huberman?

  to eat more leafy greens and supplementing with NAC and acetylcysteine, both of which can support glutathione production and detoxification, and worked to reduce my mercury levels. Comprehensive lab testing like this is so important for health, and while I've been doing it for years, I've always found it to be overly complicated. And expensive. I've been so impressed by function, both at the level of ease of use, that is getting the test done, as well as how comprehensive and how actionable the tests are, that I recently joined their advisory board, and I'm thrilled that they're sponsoring the podcast. If you'd like to try function, go to functionhealth.com/huberman. Function currently has a waitlist of over 250,000 people, but they're offering early access

• 55:38Andrew D. Huberman?

  to Huberman Lab listeners. Again, that's functionhealth.com/huberman to get early access to function. Okay, so let's think just a little bit more about how the body communicates with the brain during exercise, both in order to understand the mechanisms by which exercise improves brain health and function, but also ways that we can leverage that to improve brain health and function by using exercise. One of the more interesting and powerful, and indeed surprising ways that the body communicates with the brain during exercise to improve brain health, and indeed our ability to remember things and to learn, is the way that our bones, our skeleton, when they're under loads, okay, when they experience mechanical stress, not severe mechanical stress that would break

• 56:21Andrew D. Huberman?

  them, but mechanical stress, they release hormones, in particular, something called osteocalcin. Now, you might be thinking, wait, the bones release hormones? Yes, your bones release hormones, one of which is called osteocalcin. Osteocalcin is an incredible molecule. Animal studies that were done mainly at Columbia School of Medicine, but later also at Columbia and elsewhere in humans, have shown that osteocalcin is released from the bones during exercise, both in mice and in humans, travels to the brain, so it can cross the blood-brain barrier. And there, it can encourage the growth of neurons and their connections within the hippocampus, an area of the brain that's vitally important for the encoding of new memories. And there are some data, not a

• 57:03Andrew D. Huberman?

  ton, but there's some data, which suggests that perhaps, I want to highlight, underscore, and boldface, perhaps, can increase the number of neurons in the so-called dentate gyrus of the hippocampus to allow even better capacity for memory. Now, osteocalcin is therefore a really interesting molecule, right? Comes from bones, travels to the brain, improves functioning of the hippocampus, which is important for learning and memory. That's amazing. And it does so, in part, Through the actions of something that most of you perhaps have heard of, which is called B D N F, or brain-derived nootropic factor. Now, it's very important for us to understand that anytime we hear about exercise increases a growth factor, and by the way, exercise increases brain-derived nootropic factor,

• 57:46Andrew D. Huberman?

  it increases growth factors that cause the growth of endothelial cells, so blood vessels, we'll talk more about that in a moment, and it increases nerve growth factors. It's not just B D N F, there are lots of different growth factors, a few of which NGF and B D N F act on neurons and other growth factors that act on endothelial cells, vasculature. It seems that a lot of the effects of B D N F on the brain that are caused by doing exercise and that benefit us in terms of short and long-term memory, our ability to encode new things and remember them for long periods of time, to resist age-related degeneration, because that's the case indeed, that our hippocampus decreases in volume over time as we age, just naturally, even in somebody that doesn't have Alzheimer's dementia.

• 58:29Andrew D. Huberman?

  And exercise can adjust the slope of that decline significantly, provided there's enough exercise and the appropriate exercise. I don't think all, but many of the effects of B D N F appear to be mediated by osteocalcin. What this means is that any exercise program that's designed not just to benefit our body, but also our brain health and performance, should do something to load the skeleton in some sort of impactful way that causes the release of osteocalcin. Now unfortunately, there has not been a systematic exploration of the specific types of exercise that best cause the release of osteocalcin in humans. But based on what we understand about how osteocalcin is made and released, it seems

• 59:14Andrew D. Huberman?

  reasonable to assume and reasonable to employ some exercise within your weekly exercise that involves jumping of some sort, in particular, jumping where you have to control the eccentric or landing portion of that jump. Now, I'm certainly not the first to talk about this, it's been discussed in a different context, that is, jumping and landing has been discussed in a different context, namely by Peter Attia and others, who have talked about the fact that as people age, one of the primary Causes of mortality are the infections and the lack of mobility caused by falls that people generally have when they're going downstairs or down things. Stepping down is a common source of falls. Falls are a common source of breaking things.

• 59:57Andrew D. Huberman?

  Breaking things is a common source of inactivity and inactivity is a common source of infections and other things that lead to earlier mortality. What this means for all of us, young, middle aged and old, is that we should include some form of jumping in our weekly exercise. Now, you could imagine doing that within your high intensity interval training, provided you can do it safely and not get injured. But this is also a call for all of us to think about including, say, some jumping rope. And if you're going to jump rope, maybe not just jumping, you know, a centimeter off the ground to be able to just consistently skip, skip, skip, skip along, but maybe doing some high knees, maybe doing some double unders, if you can do those, perhaps doing some box jumps. So jumping off boxes at different heights, again, what you can do safely without getting

• 1:00:41Andrew D. Huberman?

  injured, no doubt is going to provide load to the skeleton. I guess unless you're doing it underwater and outer space, it's hard to imagine how it wouldn't. And that seems to me like the most direct way to employ this osteocalcin pathway. This pathway from the bones to the brain and neurogenesis in the hippocampus, I do believe, is likely to underlie a lot of the enhancement of learning and memory that's seen in terms of the chronic effects of exercise on brain health and brain function over time. That is, not just the things that exercise does via arousal in the minutes and hours after exercise, but the way that exercise can improve, literally, the size and structure

• 1:01:24Andrew D. Huberman?

  of one of the most critical structures in our brain that's responsible for learning and memory, the hippocampus. And of course, there are a lot of other ways that the body communicates with the brain. We definitely don't have time to go through all of them, but it's worth thinking about a few of them logically, just in terms of listing them off and thinking about how they might communicate with the brain to improve brain health and longevity. When you exercise, you utilize fuel differently, depending on whether or not you're relying on glycogen or fatty acids. And of course, it's going to depend on how long you've been exercising and the type of exercise and what you're using for fuel, literally the foods you eat, et cetera. We don't have time to go into all of that, but. Get this, turns out that there are liver to brain neural pathways.

• 1:02:05Andrew D. Huberman?

  So your liver can communicate with neurons and other cells in your brain, including the glial cells, the cells that are important for regulating energy metabolism and a bunch of other things, too. Your liver can communicate to your brain, both through neural pathways and by releasing things into your bloodstream that then communicate to your brain, "Oh, the body is using a different source of fuel. It's been using different sources or combinations of fuels for the last 20 minutes. Maybe you should adjust your brain state in order to be able to cope with that or in response to that." And of course, there are other organs in the body that are communicating with the brain also. Your diaphragm, for instance, is communicating with your brain through indirect pathways about how you're breathing during exercise.

• 1:02:47Andrew D. Huberman?

  And of course, your brain is controlling your diaphragm, too, via a number of stations, including the pathway that includes the phrenic nerve, which controls the diaphragm. The point here is that, once you start exercising, of course, that has an impact on the organs in your body. They change the way that they're functioning. Your heart, your liver, your adrenals, your skeleton, literally your bones, and of course, your muscles. And they are releasing things that impact brain function either directly or indirectly. Once you start thinking about exercise in that context, even if we don't parse each and every one of those pathways individually, you can start thinking about exercise as a multifactorial way of enhancing and changing brain activity so that it positions it to

• 1:03:31Andrew D. Huberman?

  learn better in the subsequent hours and days, as well as modifying areas of the brain, like the hippocampus, by making certain brain areas literally bigger, more powerful at engaging the sorts of things that they do. In the case of the hippocampus, learning. In the case of the prefrontal cortex, context-dependent decision-making. Updating strategies, these sorts of things. And generally speaking, exercise causes the release of things like BDNF, brain-derived neurotrophic factor, and nerve growth factor that enhance the health and stability of existing neuron connections. And something that is very rarely, if ever, discussed publicly, not because it's some sort of secret that people want to keep, but I just don't hear it discussed, is that BDNF is an activity-dependent molecule.

• 1:04:15Andrew D. Huberman?

  It's a molecule that can serve to stabilize and enhance the growth of neurons, keep their connections in place, grow new connections. And it does so when neurons are active. So the point is that BDNF has to be released in order for that to happen. But the release of BDNF itself is activity dependent. And it acts best on neurons that are already active. So if ever there was a mechanism that could explain why it is that people that exercise regularly seem to maintain healthier brains into later life, it's that one. It's that BDNF is activity dependent. And when I say activity dependent, I mean the electrical activity of neurons is what causes the release of BDNF.

• 1:04:55Andrew D. Huberman?

  And then, once BDNF is released, it has the best opportunity to stabilize and enhance the growth of existing neurons if those other neurons are already active. Now, if we were to list off all the different pathways and mechanisms by which exercise improves brain health and performance, it would be a list of probably, I don't know, somewhere between 40 and 100 different molecular pathways. And probably, I don't know, somewhere between 12 and 20 different anatomical pathways. And we certainly don't have time for all that. I don't think that's what you're interested in. And I've tried to just highlight some of the key ones today. One additional one that I'd like to highlight is the lactate pathway, or the impact of lactate when we exercise.

• 1:05:39Andrew D. Huberman?

  This is getting discussed more and more these days on podcasts and elsewhere. One interesting finding, for instance, is that lactate is what's produced when we exercise intensely. Our muscles produce lactate. And lactate is a very powerful appetite suppressant. Now, some of you may be saying, when I exercise hard, I get really, really hungry. Well, that may be true, but it's also true that if you exercise really, really hard, and then you hydrate well, and you wait a little while, oftentimes that hunger will subside. I'm not saying that you should starve yourself after exercise. Fuel as needed for you. If you're an intermittent faster, do that thing. If you like to eat right after you exercise, do that. Do what's best for you, but understand that lactate has powerful effects on our appetite. Because why?

• 1:06:22Andrew D. Huberman?

  Because lactate has powerful effects, not just on our body, but on our brain. And it is able to impact the activity of neurons in our so-called hypothalamus, little marble-sized region above the roof of our mouth, that contains some of the neurons that control our appetite. And our degree of satiety. So the point here is that lactate is a molecule produced in the body that can actually signal to the brain. Most of you perhaps have heard that lactate can be used as a fuel for neurons during exercise. Lactate is the preferred fuel for neurons under most circumstances, especially under circumstances of intense exercise. That spares glucose for other things, including for cognitive work later on. This is perhaps one of the reasons why when people do intense exercise, provided it's

• 1:07:07Andrew D. Huberman?

  not too long and too intense, and then you go to learn something, you have enhanced focus. It's because of the arousal we've been talking about all along today, but it's also because we believe that there's glucose, there's fuel that's been spared that then can be used by the neurons because during the exercise, you weren't using quite as much glucose, you were using lactate. Now lactate is also a stimulus for something called the blood-brain barrier, which is made up of endothelial cells, specialized endothelial cells that act as a barrier so that certain things, in particular, large molecules can't cross from the body into the brain. Lactate stimulates the release of something called VEGF, V G E F, which is basically an endothelial growth factor that promotes the stability and growth of the blood-brain barrier.

• 1:07:50Andrew D. Huberman?

  This is very important in the context of brain health and longevity, and longevity in particular, because one of the major features of age-related cognitive decline, and one that's greatly exacerbated in Alzheimer's, is a breakdown of the blood-brain barrier. So the integrity, the structure and function of the blood-brain barrier is something that's very important and related to brain health. And exercise that's intense enough to produce lactate causes the increase in VEGF that acts on and within the endothelial cells to improve the integrity of the blood-brain barrier. And because I mentioned the astrocytes earlier, and because I did my postdoc with somebody that was sort of famous for popularizing the study of astrocytes, when no one else wanted to study the astrocytes, now everybody studies the astrocytes.

• 1:08:34Andrew D. Huberman?

  But I have to mention something about astrocytes, which, no, they're not just a support cell. Certain types of cells in the brain are called glia. The glia come in multiple forms, oligodendrocytes in the periphery. They're called Schwann cells, but then you also have astrocytes and astrocytes sit around the synapse, they enshheat synapses. Remember synapses are the communication points between neurons and the astrocytes are beautifully positioned to read out the amount of activity that's occurring between neurons and produce fuel for those neurons. So the astrocytes mainly use glucose for fuel, but they can produce lactate. So again, we have this activity dependent phenomenon. That is, when certain neurons are very, very active, the astrocytes are able to produce more lactate, the neurons can use lactate, spares glucose, and a bunch of great things happen.

• 1:09:18Andrew D. Huberman?

  When I say great things happen, I mean in the context of the ways that exercise can improve brain function because those elevated levels of lactate in turn also increase BDNF. We already talked about the blood brain barrier. Basically, the muscles producing lactate is terrific, but the astrocytes producing lactate for the neurons to feed on is also terrific because lactate can be used as a fuel and it triggers all these downstream or subsequent mechanisms, including BDNF. So basically what we're talking about is the lots and lots of ways that exercise improves brain health in the long term, BDNF, brain plasticity, stability of synapses and so forth, maybe even new neurons, maybe, not a lot of evidence for that in humans yet frankly, but maybe.

• 1:10:01Andrew D. Huberman?

  And exercise can improve brain function in the short term through mechanisms of arousal, but also through alternate fuel usage, such as lactate from the body and from cells within the brain that we call the astrocytes and the release of all sorts of other things, IGF-1 to promote more vasculature and on and on and on. It's really quite beautiful, the sort of wave front of molecules and neural pathways that's initiated when we exercise, provided we exercise intensely enough. So this is a, you know, double and triple call for including at least some high intensity interval training, VO2 max type training each week, as well as doing resistance training.

• 1:10:40Andrew D. Huberman?

  And of course, the long duration cardiovascular training, the sort of, you know, 30 or 45 or 60 minute or maybe even two hour zone two type stuff, you can look up zone two, but it's basically a level of cardiovascular training that still allows you to talk, but were you to go any more intensely, you wouldn't be able to complete sentences.

• 1:11:00Andrew D. Huberman?

  That Zone 2 training, of course, is going to be very powerful for the health and integrity of the cardiovascular system that's going to allow for the delivery of all these molecules, and of course, the delivery of blood flow itself to the brain, because cerebral blood flow is central to brain function. Okay, so if you're right at the threshold of about to be overwhelmed by the number of different mechanisms by which exercise improves brain function and health, we're not going to add any more mechanisms. We are, however, going to talk about the practical steps that you can take to make sure that you're getting the most brain benefits from your exercise. Based on what we've talked about so far, as well as a broad survey of the literature,

• 1:11:43Andrew D. Huberman?

  and again, it is a big literature, here are the four things that I believe everyone should be doing every single week in terms of their exercise program. Now, we've talked a lot about exercise on this podcast before. I can summarize the very, very top contour of what my takeaway is from the literature and from discussions with experts such as Dr. Andy Galpin and others, which is, I believe that everybody should include both resistance training, could be body weight, free weights, machines, some combination of those, as well as cardiovascular training each week, and that the cardiovascular training should include both high-intensity interval training, at least once per week, and some so-called long, slow distance training, or Zone 2 type training each week. So presumably, most of you are doing some form of that.

• 1:12:28Andrew D. Huberman?

  So maybe you're doing more cardio than resistance training, maybe you're doing more resistance training than cardio. If you're interested in a zero-cost program where you can start to sculpt out an idealized program for you, but you want to start with a kind of general template, we have a newsletter that you can access at ubermannlab.com, zero cost. You don't even have to sign up to access it, although if you want to sign up for the newsletter, that could be valuable to you, too. Completely zero cost. You can go to hubermanlab.com, go to newsletter, scroll down to foundational fitness protocol. It describes the program that I've been following essentially for 30 plus years. And again, it's about three cardiovascular training sessions per week, three resistance training sessions per week. The cardiovascular training ranges in time from about 12 minutes,

• 1:13:12Andrew D. Huberman?

  and then a longer 60 minute session. The resistance training is generally 45 to 75 minutes, so on average about an hour. And it might sound like a lot, but when you look at that foundational fitness protocol, what you realize is that some of the workouts are really, really short. Some of them are a little bit longer. None of them are longer than an hour. So it's pretty reasonable to do. And I certainly did it while working, well, to be frank, extremely long hours for many, many years. So provided your sleep is intact and other areas of your life are dialed in with stress, etc., should be doable for most everybody. But modify it according to what you need, or if you're doing something completely different, more power to you. I just want you to know that's available

• 1:13:53Andrew D. Huberman?

  as a zero cost resource if you want to check it out. With all of that said, whatever exercise you happen to be doing, or you happen to be planning, I do believe it should include four things specifically to improve brain health and performance. Although these four things will also benefit you at the level of your bodily health, no doubt. The first thing is to include at least one workout per week that is of a long, slow distance nature. So zone two type cardio, maybe you get a little bit up into zone three, but basically jogging, swimming, rowing, any activity that you can carry out consistently for 45 to 75 minutes without getting injured. Right? People always say, well, do I have

• 1:14:36Andrew D. Huberman?

  to run? No. If you don't like running and running's too hard on your body, or you'll get injured, then do something else. Maybe you do the rower, maybe you ride a stationary bike, maybe you ride a road bike. For me, it's jogging generally, or hiking with a weight vest. Those are the things that I enjoy and that I can do without getting injured. But for other people, it's a different, it's a different exercise. But at least one long, slow distance training session per week is going to be very beneficial for brain health because of the way that it impacts cerebral blood flow, endothelial health, and basically the way that cardiovascular health improves brain function at the level of blood flow, fuel delivery, etc. The second thing is to include at least one workout per week. That's of the so-called high-intensity interval training type.

• 1:15:19Andrew D. Huberman?

  Now, there are a lot of different types of high-intensity interval training out there. In fact, Dr. Andy Galpin says, you know, we'll hear about, say, like the four by four by four protocol, right? Four minutes of going as hard as you can for four minutes. Basically where there's no variation in the intensity through that whole four minutes. You're going hard the whole four minutes, but only as hard as you can for the entire four minutes. Then resting four minutes and then repeating that four by four cycle four times. So that's one way to do it. But Dr. Andy Galpin would be the first to tell you that you probably also get great results from a three by three by four type of workout or a six by six by six type of workout. Although for many people, that's going to be too much and too intense.

• 1:16:00Andrew D. Huberman?

  Or if you're me and you prefer a high-intensity interval training session that is more like a two minutes on as hard as you can go for two minutes and then rest for, say, three to four minutes and then repeat maybe four times, maybe five times, well, then do that. I have a high-intensity interval training session that I do when I'm very limited on time, which involves getting on the Airdyne bike. They sometimes call the assault bike. There's a lot of resistance, has that fan, which I always thought was to cool me off. But then, you know, it's, uh, once I actually got on one and, and, and started riding, I realized that that's to provide resistance. So, but basically if I'm limited on time, I'll hop on there, I'll pedal for about a minute or two, just kind of warm up and then I'll go all out for a minute, rest for 30 seconds, all out for a minute, rest for 30 seconds.

• 1:16:44Andrew D. Huberman?

  The first three or four of those cycles, feeling pretty good. By the seventh and eighth one, I'm, you know, I'm praying. And generally when one finishes that type of workout, your heart rate is very, very elevated. Now, I don't tend to track my heart rate during exercise. Perhaps I should, but I don't like to get, you know, too weighed down with technology when I exercise. I like to go more on feel. That's just me. I find that my heart rate is extremely high right as I get off that thing. But you know, five minutes later, it's back to baseline. And I certainly feel energized after doing that to go do some cognitive work, to shower up and to head to work, that sort of thing. So pick a high intensity interval training session that you can do at least once per week. And that works for you.

• 1:17:28Andrew D. Huberman?

  And again, it's really important to pick a form of exercise for the high intensity interval training that you can do without getting injured. This is so important. You know, one way to really limit your brain health and bodily health is to get injured and to not be able to exercise. In a few minutes, I'll tell you about what happens when you don't exercise for a certain duration and how that negatively impacts your brain health. And it's not that long before that starts to happen. But in the meantime, the first was long, slow distance or so-called zone two. So we could call that LSD, not the psychedelic, but long, slow distance exercise. Second was high intensity interval training or H I I T or HIT. The third would be TUT, T U T, time under tension.

• 1:18:11Andrew D. Huberman?

  If you're doing resistance training, and I do believe everybody should be doing resistance training, there are a near infinite number of different ways to do resistance training, as you well know. You can move the weight ballistically, you can control the eccentric, you can do any number of different things. But some proportion of the exercises that you do during your resistance training during the week should include time under tension training where you're really emphasizing the contraction of the muscles, the slow lowering of the weight as well as the lifting of the weight, contracting the muscles as hard as you can. And this is really to emphasize the nerve to muscle pathways and the way that time under tension promotes the release of things from muscles into the bloodstream that can positively impact the brain

• 1:18:51Andrew D. Huberman?

  as well as the way that focusing your brain on exercises such that you're isolating muscles, or even if you're not doing a so-called isolation exercise, maybe you're doing a compound exercise, like a dip or a squat or a deadlift, but that really concentrating on the muscles that are supposed to be managing the work and not just moving the weight, but challenging the muscles. This is very important thing, challenging the muscles, using the weight, not lifting weights or moving weights. By focusing on time under tension, you will of course, get benefits as it relates to hypertrophy and strength increases, in particular hypertrophy. Doing time under tension requires you to engage the, what we call the upper motor neuron to lower motor neuron. You have motor neurons in your cortex, you also have motor neurons.

• 1:19:35Andrew D. Huberman?

  And your spinal cord, those pathways that then go out to the muscles and control the muscles in very deliberate ways. And time under tension training is very beneficial for the deployment of the molecules that work both within the body, but also within the brain to support brain health and function, both in the short term and most particularly in the long term. I'd like to take a quick break and thank one of our sponsors, Maui Newey Venison. Maui Newey Venison is 100% wild harvested venison from the island of Maui, and it is the most nutrient dense and delicious red meat available. I've spoken before on this podcast about the fact that most of us should be consuming about one gram of quality protein per pound of body weight every day. That protein provides critical building blocks for things like muscle repair and synthesis,

• 1:20:20Andrew D. Huberman?

  but it also promotes overall health, given the importance of muscle tissue as an organ. Eating enough quality protein each day is also a terrific way to stave off hunger. One of the key things, however, is to make sure that you're getting enough quality protein without ingesting excess calories. Maui Newey Venison has an extremely high quality protein per calorie ratio, so that getting one gram of quality protein per pound of body weight is both easy and doesn't cause you to ingest in excess of calories. Also, Maui Newey Venison is absolutely delicious. They have venison steaks, ground venison, and venison bone broth. I personally like all of those. In fact, I probably eat a Maui Newey Venison burger pretty much every day, and occasionally I'll swap that for a Maui Newey steak. And if you're traveling a lot, or you're simply on the go, they have Maui Newey Venison

• 1:21:05Andrew D. Huberman?

  sticks, which have 10 grams of protein per stick at just 55 calories, and they're extremely convenient. You can pretty much take them anywhere. Responsible population management of the access to you on the island of Maui means they cannot go beyond a particular harvest capacity. Signing up for a membership is therefore the best way to ensure access to their high quality meat. If you'd like to try Maui Newey Venison, you can go to maowinewivenison.com/huberman to get 20% off your membership or first order. Again, that's maowinewivenison.com/huberman. Okay, so we have long, slow distance, high intensity interval training, and some degree of time under tension training with resistance training.

• 1:21:46Andrew D. Huberman?

  You might be asking, how many sets? What proportion? That depends on your goals, right? If you're a power lifter and you're trying to lift bigger weights, or you simply want to get stronger, you're not going to devote a lot of your training to time under tension, most likely. You're going to be focusing mostly on the performance of those lifts to move more weight. But in my case, what I do, just for sake of example, again, this is just what I happen to do, is I tend to make a full third of my resistance training just focused on time under tension. So if I do two exercises, typically the first exercise is a compound exercise. So if it's a shoulder press, for instance, I'll do a couple of warm-up sets and then the work sets. I try and move the weight. And generally, I tend to work pretty heavy in the, for me, heavy for me, in the four to eight repetition range.

• 1:22:28Andrew D. Huberman?

  I'll try and move the weight as quickly as I can on the concentric phase, the lifting phase, and then at least twice as slow on the lowering phase. And then I pause while keeping the muscles under tension. I never really set the weight down at all during a set, if I'm doing my job, that is.

• 1:22:44Andrew D. Huberman?

  And then the second exercise that I do, I really focus even more on time under tension. So whether or not it's a compound exercise or an isolation exercise, again, compound exercise, multiple joints moving, isolation exercise, single joints moving, I'll really concentrate on keeping the muscle under tension the entire time. In fact, I'll lift the weight off the stack, if it's a machine, or if it's a free weight, just a little bit, engage the muscles that I'm trying to activate or train, and then keep it under tension throughout the concentric, the contraction, and the lowering of that weight, and then never actually set it down until the end of the set, AKA increasing the time under tension. And then the fourth category of exercise that I believe everybody should include

• 1:23:26Andrew D. Huberman?

  in their existing workouts, or add if you're not currently working out, is some sort of explosive jumping and/or eccentric landing. Now, the explosive jumping with eccentric landing, you could do on a mat, right? Most people won't do it on concrete because they're worried about impact, that sort of thing. But let's say you have some mats or you're on a lawn or you're on dirt or you're, you know, jumping up onto a box as high as you can and then jumping down and controlling the eccentric portion. Again, pick something that you can do safely, progress slowly, right? If you're going to jump up and off boxes, you want to start with low boxes. I know that many of you can jump quite high and I'm not one of those people, but if you can jump quite high and then you're going to jump off that box and you're going to

• 1:24:11Andrew D. Huberman?

  do this as a new thing, you'll notice that anytime you add eccentric training to your workout regimen, it tends to increase soreness a lot. And often people get injured by including a new form of movement, in particular form of movement that you can fall and/or not just falling, but by including a lot of eccentric movements that they hadn't been doing previously. Again, be really safe about this, but that loading of the skeleton through eccentric movement and controlling the descent, super important, not just for your body, not just to avoid falls, not just to improve coordination and a bunch of other great things, but also to get that release of osteocalcin, the improvements in BDNF, brain performance, brain health, and so on. And I'm guessing that most of you can probably

• 1:24:54Andrew D. Huberman?

  incorporate these four things, long, slow distance, high intensity interval training, some deliberate time under tension training during your resistance training. Again, could be done with body weight, doesn't have to even be done with machines or free weights, as well as some explosive and eccentric control training without adding any time to your existing workout regimen, simply by incorporating it into whatever workouts you happen to already be doing. And the explosive eccentric control training could be done frankly, at the end of a run, you could do it at the end of your zone two day, you could do it on the end of a HIIT day. Whenever you do it and however you do it, just try not to get injured. That's the most important thing. Why? Well, it turns out if you get injured, you can't exercise. Sometimes you can, and it's good to continue

• 1:25:36Andrew D. Huberman?

  exercising, provided you're not aggravating that injury, but a lot of times you can't. And there are actually studies of how quickly your brain starts to suffer if you don't exercise. Now, most of these studies have been done on Very experienced athletes, where people that are exercising a lot and then are forced to detrain or stop training completely. And in some of these studies, they've done this independent of anything else. It's not like these people got sick from a, you know, a cold or flu and then had to stop training. They'll just have them train a lot and then stop training and then start to look at some of the effects that occur within the brain. And the major thing that I was able to extract from that literature is that after about 10 days of not doing any training, that is, no cardiovascular training, no resistance

• 1:26:16Andrew D. Huberman?

  training, you start to see significant decrements in brain oxygenation levels, as well as some other markers that are indicative of brain health, or that would be indicative of brain health if they were to continue. So if you haven't been training at all for a long period of time, your brain is suffering. The good news is, you can start benefiting your brain very quickly by exercising. Check out the foundational fitness protocol and involves a ramp up or warm in kind of phase because you don't want to jump into something whole hog if you haven't been doing it at all, if you haven't been exercising at all, you know, forget what you did in high school. By the way, folks, anytime people tell you, "Back in the day, I was so fit," that's not the way to think about it. It's about today and what you're going to do today and forward, okay? The past is great, it tells you you had a capacity, but you really just want to take

• 1:27:01Andrew D. Huberman?

  where you are now and try and improve where you are now going forward, okay? The past is the past. So how fit you were in high school or in junior high school, or when you were in the kindergarten class, you were the first one to make it around to get the blocks and the cookie in the milk first, like, awesome. But if you're going to start up having not exercised in a long, long time, think about what you can do now so you don't get injured, because when you get injured, you can't exercise. And when you don't exercise for 10 days or more, that's when you start to see decrements in brain health. So if you're not exercising now, it's a great time to get to it. If you are exercising now and you have to take a week off because of some sort of illness or injury or family event or stress, look, don't. Obsess over that. Don't miss out on some of the key things of life or make yourself

• 1:27:44Andrew D. Huberman?

  sicker by exercising. And please, please, please don't come to the gym sick. Okay? I did a whole episode on colds and flus. And anytime people are coughing and sneezing, and they tell you they're not contagious, that's completely unsubstantiated by the scientific data. Please don't come to the gym sick. So if you had to take a week off, you'll be fine. You'll be fine. You'll probably come back stronger in the end. Take a couple of days and ramp back up. But after about 10 days, your brain health starts to suffer. So that's an important number to keep in mind. Okay, so multiple times throughout today's discussion, we've been talking about how exercise increases arousal, arousal improves brain function. That's true. You know what's also true? What's also true is that exercise improves brain health in the long term. Yes, through the deployment of things like BDNF.

• 1:28:26Andrew D. Huberman?

  Yes, through the deployment of things like osteocalcin, and on and on. But it also does so by improving your sleep. There are now many, many studies showing that sleep is the thing that mediates many, not all, but many of the positive effects of exercise on brain performance and long term brain health. So what this means is that you have to make sure that you're getting adequate amounts of sleep. It's not sufficient just to exercise. You need to get proper sleep. And I've done multiple episodes on how to optimize your sleep, how to improve your sleep, how to deal with insomnia, shift work. If you want to learn about any and all of that, either from podcasts or from our newsletter, go to hubermanlab.com, put sleep into the search function, and it will take you to

• 1:29:09Andrew D. Huberman?

  the episodes and the newsletters that discuss that. In addition, if you have a specific issue with sleep, like you're doing shift work, or you're jet lagged, or you are suffering from middle of the night waking, or trouble shifting your schedule because you want to become an early riser, put those terms into the search function. It will take you to the specific timestamps in those episodes, so that you don't have to listen to the entire episodes, because I realize that some of them are quite long. And of course, there's the newsletter on sleep that lists off the various things that you should and can be doing to improve your sleep, no matter how well you happen to be sleeping now. But tons and tons of zero cost resources there in PDF form, in podcast form, and on and on.

• 1:29:51Andrew D. Huberman?

  We also did the six episode series on sleep with Dr. Matthew Walker, one of the world's experts in sleep. So that's also there. So you can find all that there.

• 1:30:00Andrew D. Huberman?

  One question I get a lot is, let's say I don't sleep that well. Should I exercise? Well, the short answer is yes, provided that it was just one night of poor sleep. In fact, there are studies showing that if you're slightly sleep deprived, meaning one night's poor sleep. So, most people need somewhere between six and nine hours of sleep. Varies by person, varies by age, varies by time of year, and so on. All discussed in that series with Matt Walker.

• 1:30:27Andrew D. Huberman?

  Most people need six to nine hours, but let's say you normally get eight or you normally get seven, but you're down two hours on sleep for whatever reason. Should you exercise the next morning? The short answer is yes, provided it was just one night of poor sleep. It turns out that exercising after a poor night's sleep can help offset some of the negative effects of sleep deprivation on what? On brain performance and health. Now, you don't want to get into a habit of this. You don't want to get into a habit of using exercise as a way to compensate for sleep loss. So, if you don't sleep well for one night, exercise is a great way to offset that sleep loss effect on the brain or that would otherwise affect the brain. You can compensate for it by doing some exercise. Keep in mind, you want to exercise in a way that's not too intense

• 1:31:12Andrew D. Huberman?

  because you can drive your immune system down and be more vulnerable to infections. That's certainly the case after a poor night's sleep. You also want to be really careful with what you do for that exercise in terms of your coordinated movement. It's much easier to get injured when you're sleep deprived. In fact, there's a really nice set of studies. Lee Norton's talked about this elsewhere, that the relationship between sleep, or I should say, sleep deprivation and injury is a strong one, and the relationship between sleep loss and pain and failure to recover from injury is also a strong one. The direct point being, if you're slightly sleep deprived, sure, go ahead and exercise. That will actually help you offset some of the negative effects of that sleep deprivation. But you want to be careful how you exercise so you don't get sick and you don't get injured. So, you can keep in mind that if you're having trouble sleeping

• 1:31:56Andrew D. Huberman?

  or even if you're a great sleeper already, getting exercise will further improve the architecture of your sleep. In fact, there's some evidence that doing high intensity interval training can improve the amount of deep, slow wave sleep that you get. And there's some additional data showing that if you do high intensity training early in the day, And that's combined with a bunch of other things that stimulate autonomic arousal. So here we are again at autonomic arousal. Things like caffeine, if that's in your program, you don't have to drink caffeine. Things like getting bright light in your eyes early in the day. Definitely do that. Don't stare at the sun or any light so bright that it's dangerous or painful to look at, but certainly get bright light in your eyes. All those things that increase autonomic arousal early in the day can also help improve the amount and the quality of sleep that you get at night.

• 1:32:38Andrew D. Huberman?

  In particular, rapid eye movement sleep, which is so critical for learning and memory. In fact, there's something called the first night effect, which is the amount and quality of rapid eye movement sleep that you get on the first night after trying to learn something powerfully dictates whether or not you actually learn and remember that thing. Because as you recall, learning and memory neuroplasticity is a two-step process. You need to be focused and alert during the encoding phase, during the learning, but it's in states of deep rest, sleep in particular, but also non-sleep deep rest. But rapid eye movement sleep is the kind of king of reshaping your brain connections for the better, unloading the emotional load of experiences that were troubling. That happens during rapid eye movement sleep. Just a little bit of REM deprivation, rapid eye movement sleep deprivation

• 1:33:22Andrew D. Huberman?

  will make you more emotional and will make the painful experiences of recent and distant past also more painful. Get more rapid eye movement sleep if you can. It also consolidates learning of things that you want to remember. Again, exercise early in the day, in particular, high intensity exercise, combined with some of the other things we just discussed. Terrific way to improve the amount and quality of sleep that you get at night. And of course, all of that geysers up to what? Better brain health and performance in the short term and in the long term. Okay, so I listed off the four types of training that you absolutely want to include in your exercise regimen if improving your brain health and performance is one of your goals, and obviously that should be one of your goals. Your brain is your central command center for your entire brain, but also your body.

• 1:34:06Andrew D. Huberman?

  There's a fifth category of exercise that everyone should include if one's goal is to have a better and more resilient and indeed a better performing brain compared to your age match controls. And to be direct, that fifth category is the one that you absolutely don't want to do. What do I mean by that? Well, there's an absolutely beautiful literature about a brain area. I've talked a little bit about this before in our episode about tenacity and willpower. I've talked about it on a few other podcasts as well. It came up. During the podcast episode that I did with the one and only David Goggins, and that brain area is the anterior mid-Cingulate cortex.

• 1:34:48Andrew D. Huberman?

  The anterior mid-Cingulate cortex, very briefly, is a brain area that is powerfully engaged when we lean into challenges, including physical challenges, but also mental challenges, emotional challenges, and we get that "I'm gonna push through" tenacity and engaging our willpower. Now, it's remarkable to think about this brain area. This is a brain area, mind you, that when my colleague at Stanford, Joe Parvizi, putting a little electrode into, he was doing this for other reasons related to important neurosurgeries that patients needed, and stimulated that particular brain area, anterior mid-Cingulate cortex, people reported immediately feeling as if there was some impending challenge, but that they were gonna lean into that challenge. Remarkable.

• 1:35:31Andrew D. Huberman?

  This brain area has intense connectivity with many, many other brain areas, the dopaminergic system, the so-called arousal system, so multiple brain areas involved in arousal. Areas of the brain that are involved in learning, areas of the brain that are involved in stress, areas of the brain that are involved in lots and lots of different things. It's a major hub for inputs from other brain areas and outputs to other brain areas. But here's what's most remarkable about the anterior mid-Cingulate cortex. There's a category of humans referred to as superagers. Superagers are people that defy the aging process, at least at the level of cognition. They maintain the volume of certain brain areas well into older age when their age-matched counterparts are losing the same brain areas.

• 1:36:15Andrew D. Huberman?

  Meaning, people in their 60s, 70s, 80s, 90s have brain areas that are shrinking. Even in cases where people don't have Alzheimer's dementia, areas of the brain are shrinking. Superagers are people that maintain the healthy, full volume of these brain areas, and indeed, in some cases, the volume, the size of these brain areas continues to increase into their later years. One of the brain areas that maintains or increases volume in these superagers is the anterior mid-Cingulate cortex. And there aren't many other brain areas that do that. The anterior mid-Cingulate cortex is the main site that can be tacked to this phenomenon of superaging. Now, superaging and superagers is a bit of a misnomer because what's happening in these people is they're not just holding on to the volume of their anterior mid-Cingulate cortex,

• 1:36:59Andrew D. Huberman?

  they're also maintaining healthy cognition, which is flexible, strategy, context-dependent learning, their memory, their working memory. They're doing phenomenally well, not just for their age, but even compared to some much younger people. So these superagers are really interesting, both for sake of what they can do into their later years, and because their anterior mid-Cingulate cortex is holding on to its size and in some cases, increasing its size. What can allow you to activate and increase the size of your anterior mid-Cingulate cortex? Well, it's very simple, to do things that you don't want to do. I should be very clear, we're talking about things that can be done safely, that aren't going to damage you physically or psychologically.

• 1:37:41Andrew D. Huberman?

  But we are talking about exercise, or in some cases cognitive exercise, but today we're talking about physical exercise, that you would much rather not do. So if you're like me and you love resistance training, it can be hard, right? Some days I want to do it more than others, and sometimes the workouts are much harder than others, but I love it. But if I want to maintain and increase the size of my anterior mid-Cingulate cortex, I absolutely have to find some form of physical exercise that I would much rather not do, but as I mentioned before, that's also safe physically, and that's not going to damage me emotionally. I don't know what kind of physical exercise would damage me emotionally, but you get the point. This brain area has been explored in a number of different studies, so successful dieters increase the size of their anterior mid-Cingulate cortex.

• 1:38:24Andrew D. Huberman?

  People that fail to reach a goal, a diet goal or other goal, experience a shrinking of their anterior mid-Cingulate cortex. There's also examples of physical exercise increasing anterior mid-Cingulate cortex.

• 1:38:37Andrew D. Huberman?

  Skill challenges and on and on. The important point is that the anterior mid-Cingulate cortex is agnostic with respect to what you do, except that it has to be something that you don't want to do if you want to build and maintain its size. And that building and maintaining of the anterior mid-Cingulate cortex size is strongly correlated. It's not necessarily causal, but it's strongly correlated with this super aging phenomenon. There's a wonderful review about the anterior mid-Cingulate cortex that was authored by none other than Lisa Feldman Barrett. She came up earlier in this episode. She's a world-class researcher on the topic of emotions and the basis of emotions, et cetera. The title of this paper is "The Tenacious Brain: How the anterior mid-Cingulate cortex contributes to achieving goals."

• 1:39:21Andrew D. Huberman?

  And there's one figure in this paper, and I just want to summarize a couple of things from, because it's just like a wow figure. There aren't many figures like this. I mean, this is a review article, so this figure includes panels pooling from a bunch of different studies, but I'm going to just highlight a few of these by paraphrasing what's in the figure legend. Okay? So bear with me here. I think you'll find this very interesting. Okay? So you can't see the pictures because many people are listening to this on audio, but you can certainly look up the paper. We provide a link to it in the show note captions. But these points are worth paying attention to. Spontaneous anterior mid-Cingulate cortex activity predicts grit, this psychological phenomenon that we refer to as grit. Now, this was teased out in a study of grit. Grit is this ability to lean into challenge.

• 1:40:06Andrew D. Huberman?

  And the mere spontaneous activity, right? Not evoked activity. There's spontaneous activity, which is the activity that occurs sort of naturally as a consequence of engaging in a particular thought pattern or behavior. And then there's evoked activity when you stimulate a brain area. This is spontaneous activity. Spontaneous anterior mid-Cingulate activity is associated with the psychological phenomenon, the verb that we call grit. And grit can be thought of as an adjective, right? Somebody's really gritty, but it should best be thought of as a verb. It's the leaning into challenge. Greater anterior mid-Cingulate cortex activity is associated with higher levels of persistence. This again was teased out in a study of persistence. So these aren't just philosophical statements or theoretical statements.

• 1:40:49Andrew D. Huberman?

  These are based on brain imaging studies where people are being challenged with a particular set of challenges while they're in a so-called FMRI, functional magnetic resonance imaging machine. Activation of the anterior mid-Cingulate cortex is associated with grit and with persistence. And anterior mid-Cingulate signal is associated with willingness to exert more effort. If people have to exert more effort and they're willing to do that, boom, anterior mid-Cingulate cortex activity goes up. Also, anterior mid-Cingulate activity increases, get this, during effort magnitude estimation. Even when people are just trying to gauge how much effort something's going to take, that starts to initiate activity of the anterior mid-Cingulate cortex. The, oh boy, this is going to be a big one. I gotta do this.

• 1:41:34Andrew D. Huberman?

  And I'll explain how I engage my anterior mid-Cingulate cortex. You'll have to decide if that's something that you hate enough so that you can use it too. Almost done here, folks. Anterior mid-Cingulate signal tracks the subjective value of effort exerted. As people start to track how much effort they're exerting, anterior mid-Cingulate cortex activity goes up. And last but not least, anterior mid-Cingulate cortex stimulation, so this is no longer spontaneous activity, but stimulation increases the will to persevere. Incredible. Never before, meaning never before, reading this article and learning about anterior mid-Cingulate cortex, which again is largely the consequence of work done somewhere between the years of 2010 and now, 2025.

• 1:42:18Andrew D. Huberman?

  Did we even understand what the anterior mid-Cingulate cortex is there for and is doing? It could do other things too, but this is an extraordinary set of findings and an extraordinary brain structure that everyone should know about. And that's why number five on that list, if you want to improve brain function and brain health over time, is to do something you really don't want to do, something really challenging, both psychologically challenging and physically challenging, at least once per week. Make sure it's safe psychologically and physically, but do that thing. For me, I must confess. It's deliberate cold exposure, but it's deliberate cold exposure under particular conditions. I'll be the first to say that I love getting into the ice bath, or the cold plunge, or

• 1:43:01Andrew D. Huberman?

  taking a cold shower after I've been in a hot sauna for 20 or 30 minutes, or after a long run where I'm sweating and I want to cool off, or on a hot summer day. But most of the time, that's not the case, meaning, most of the time when I do deliberate cold exposure, and sometimes I'll do it by cold shower, which by the way, is zero cost, it'll even save you on your heating bill, so you don't need to buy any equipment, or you could do a cold plunge, or an ice bath, but you don't need one. Most of the time, when I even think about getting into the cold plunge, or taking a cold shower, that is very likely increasing my anterior mid-Cingulate cortex activity, because I love, love, love the heat, I love sauna, I'm very heat adapted, I'm comfortable at very high temperatures in the sauna. I don't hate the cold, but I close to hate the cold.

• 1:43:45Andrew D. Huberman?

  So for me, the first wall to get over, the first bit of resistance that's really hard for me to get over, is to walk towards the cold plunge, then it's to take the lid off, then it's to look at the thing, then it's to get in. But I force myself to do it, I make sure that I do it safely, and I make sure that I do it for about one to three minutes, sometimes longer, but I do it because, yes, deliberate cold exposure increases release of the so-called catecholamines, dopamine, epinephrine, norepinephrine. Also, yes, I know that those catecholamines are going to make me feel much better after I get out of the cold plunge for many, many hours, that's been established. But I also do deliberate cold exposure by cold shower, or by cold immersion, because I hate it. And because I know that by doing it, I'm going to be activating my will to persevere, my grit, my willpower.

• 1:44:30Andrew D. Huberman?

  Now, today's discussion is not about deliberate cold exposure, it's about exercise. So what I've started doing in recent months, and I'm certainly going to continue into 2025, is to start adding some form of exercise that I absolutely don't want to do, in order to activate my anterior mid-Cingulate cortex. Now, for me, because my schedule is very full, I'm already doing six workouts per week, again, some of them are shorter, some of them are longer, I don't have a lot of extra time to exercise, I don't have a lot of time to start rolling jiu-jitsu for a couple hours a week, which I wouldn't loathe, but there's a big barrier for me to do that sort of thing. So maybe it's perfect for activating AMCC, anterior mid-Cingulate cortex. Rather, what I've decided to do... Is to include the one thing that I've been putting off for years that frankly,

• 1:45:15Andrew D. Huberman?

  I may enjoy down the line, but that I don't enjoy currently. And that's to do some sort of really coordinated, specific motor activity that has to be done precisely or very precisely before you can say that you've quote unquote, done it right. And for me, the thing that I'm selecting, because I already like to jump rope and I can do a few different things with a jump rope. I'm not super skilled, but I can already jump rope. It's something that my friend Mark Bell exposed me to, which is this rope flow thing. Feel free to laugh if you want, but this stuff is hard and it's really, really cool. The rope flow involves just taking a rope. Okay. There may be specific commercial brands of these, but I was told I can just use a kind of thick rope that you buy at the hardware store or like a dog leash type rope. And you can look this up online. We'll provide a link to it.

• 1:46:00Andrew D. Huberman?

  There's a specific pattern of moving the rope where you're not actually jumping through it. So it's not jumping rope, but you're actually moving it in front of and behind your body and from side to side and involves a lot of different shifting from one limb to the other in very deliberate ways. And as I'm discussing this, I realized that I really don't want to do this, but I know it's going to be very useful for me, which is exactly why I'm going to use it in 2025 to enhance my anterior mid-Cingulate cortex activity. The only fear being that I'm going to start to like it and then I'll have to find something else to engage my anterior mid-Cingulate cortex. And perhaps at that point, I'll look to you guys in the comment sections to figure out what sorts of exercise I would hate the most in order to make sure that I'm getting my

• 1:46:39Andrew D. Huberman?

  anterior mid-Cingulate cortex activation because yes, increased coordination is great. Who wouldn't want that? But mainly because I want to improve my brain performance and brain function, both in the short term and over time. So if you want in the comment section on YouTube, because that's where I can see the comments best, or perhaps on Spotify as well, where they now have a comment section. I guess Apple has a comment section too. YouTube, Apple or Spotify, put in the comment section, the form of exercise that's both psychologically and physically safe for you to embrace. But that you would loathe to do and that you're going to perhaps, no, not perhaps, that you're going to commit to doing in 2025. And then we can compare and contrast and we can all see which ones we hate the most.

• 1:47:23Andrew D. Huberman?

  And then we can exchange which exercises we hate the most. And everyone can laugh at us for doing these things that we hate. And yet we'll be the ones laughing because our anterior mid-Cingulate cortices will be nice and plump well into our old ages and everybody else will be wondering where the comments section is. Thank you, everybody, for joining me for today's discussion, all about how exercise can be leveraged to improve brain health and brain performance. If you're learning from and/or enjoying this podcast, please subscribe to our YouTube channel. That's a terrific, zero-cost way to support us. Please also click Follow for the podcast on both Spotify and Apple. And on both Spotify and Apple, you can leave us up to a five-star review. Please also check out the sponsors mentioned at the beginning and throughout today's episode. That's the best way to support this podcast.

• 1:48:07Andrew D. Huberman?

  If you have questions for me or comments about the podcast, or topics or guests that you'd like me to consider for the Huberman Lab podcast, please put those in the comments section on YouTube. I do read all the comments. And if you're not already following me on social media, I am Huberman Lab on all social media platforms. So that's Instagram, X, formerly known as Twitter, Facebook, Threads, and LinkedIn. And on all those platforms, I discuss science and science-related tools, some of which overlaps with the content of the Huberman Lab podcast, but much of which is distinct from the content on the Huberman Lab podcast. Again, that's Huberman Lab on all social media platforms. And if you haven't already subscribed to our Neural Network newsletter, the Neural Network newsletter is a zero-cost monthly newsletter that includes everything from podcast summaries

• 1:48:50Andrew D. Huberman?

  to what we call protocols in the form of brief one- to three-page PDFs that cover things like how to optimize your sleep, how to regulate your dopamine. We also have protocols related to deliberate cold exposure, get a lot of questions about that, deliberate heat exposure, and on and on. Again, all available at completely zero cost. You simply go to hubermanlab.com, go to the menu tab in the top right corner, scroll down to newsletter and enter your email. And I should mention that we do not share your email with anybody. Thank you once again for joining me for today's discussion, all about exercise, brain health, and performance. And last, but certainly not least, thank you for your interest in science.

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