WHOOP Podcast - How Exercise Improves Cognitive Function & Longevity with Dr. Tommy Wood

Episode Date: December 7, 2022

This week’s episode is all about unlocking the exercises to improve long-term cognitive function and brain health. WHOOP VP of Performance Science Kristen Holmes is joined by neuroscientist Dr. Tommy Wood to discuss his background in neuroscience and pediatrics (2:50), the mind-body connection (4:38), the framework for optimal brain health (6:40), the importance of committing to sleep (10:58), how nutrients affect overall brain health (16:00), the effect of creatine and creatinine (20:15), how general movement influences the brain (22:05), the amount of exercise needed to see a positive change in cognitive function (25:33), how reducing stress can lead to better brain health (28:13), the best ways to recover to improve cognitive function (31:40), how to start exercising to optimize brain health (34:19), developing a strength training program (37:45), training to avoid dementia and improve long-term health (41:27), the ideology of Movement Snacks (46:06), and how to find Tommy’s research (49:10).Resources:Dr. Tommy Wood on InstagramDr. Tommy Wood on TwitterEllen J. Langer Study on Sleep Duration and Cognitive PerformanceMarc Hamilton Study on Seated Calf RaisesSupport the showFollow WHOOP: www.whoop.com Trial WHOOP for Free Instagram TikTok YouTube X Facebook LinkedIn Follow Will Ahmed: Instagram X LinkedIn Follow Kristen Holmes: Instagram LinkedIn Follow Emily Capodilupo: LinkedIn

What's up, folks. Welcome back to the Whoop podcast. This is our 200th episode, which is pretty amazing. We've been sitting down with the top athletes, performers, researchers, scientists, and more to learn what the best in the world are doing to perform at their peak. And I remember saying a few years ago now, okay, we'll do 10 episodes and see how it goes. So here we are. We're on episode 200. A big thank you to all of our listeners.

I'm your host, Will Ahmed, founder and CEO. of Whoop, and we are on a mission to unlock human performance. On this week's episode, our VP of Performance, Kristen Holmes, is joined by Dr. Tommy Wood. Dr. Wood is a senior fellow in the Pediatrics Department at the University of Washington and Chief Scientific Officer of Norish Balance Thrive, a company devoted to optimizing performance in athletes. He is an expert in strength trading and has also coached and competed in multiple sports, including rowing, crossfit, powerlifting, and ultra-endurance raising. He is a true expert in the connection of the brain and body and knows just how to train physically to set the

brain up for long-term health and success. Dr. Wood and Kristen discuss the connection between the mind and body, how exercise and training can improve cognitive function, improving long-term brain health, tips to reduce the effects of aging, the cognitive difference between strength and cardio training, the best way to create a comprehensive training program, and how metabolic health can influence the mind and body connection. As the holiday season approaches, it's the perfect time to gift whoop to your friends and family. There's no better way to kickstart your year

and get your resolutions off right than with a personalized fitness and health coach. You can check that out at whoop.com. And if you're new to whoop, use the code will when you're checking out and get a $60 credit on WOOP accessories. That's WI-L-L. If you have a question, you want to see answered on the podcast, email us, podcast to Woop.com.

call us 508-443-4-9-5-2, and we will answer your question on a future episode. Now, let's get to Kristen Holmes and Dr. Tommy Wood. We are thrilled to welcome Dr. Tommy Wood. Tommy's research interests include the physiological and metabolic responses to brain injury and how that impacts brain health across the lifespan. Tommy is also a leader in developing easily accessible methods to track health, performance, and longevity in both elite athletes and the general population. Our conversation today will focus on exactly what those easily accessible methods are

to ensure we're setting ourselves up to be independent, free of disease, and maximize our quality of life. Tommy, your PhD research was focused on neonatal brain metabolism. As a place to start, would love for you to explain how those core components run across the life course. Yeah, sure. And thanks for that opening question. Often people wonder, or I exist in two buckets, which you kind of explain.

So in one bucket, I have this work with elite athletes and people in the general population to try and make them perform as best they can for as long as they can. And then in this other bucket, I do basic neuroscience, mainly a neonatal brain injury, but also traumatic brain injury. And people are like, well, why is a neonatal neuroscientist talking to me about cognitive decline or physical performance? And there's kind of two things that I did separately because there were just things that I was interested in. And then the more time I spent doing it, the more I realize that what's important for the brain early in life, which is where I do a lot of my basic neuroscience, is actually sets us up to understand what's important for your brain across your entire lifespan. So the things that are important for building a healthy brain in the first place, the way we stimulate it, the way we nourish it. Those are the things that we should keep doing throughout our entire lives to keep our brains functioning as best as possible. So actually the sort of early life really informs later life.

And all the same things are important. And, you know, I know we'll dig into all of them, but physical activity, social connection and stimulus, sleep and recovery, obviously, nutrition. You know, all those things really should form the bedrock of what you should do to keep your brain healthy and happy for as long as possible. Right. Well, I'm definitely excited to, you know, we talk a lot about sleep and recovery. And we will tap into that for sure. But really want to spend a bulk of our time, you know, talking about exercise, actually, and really digging in. to how different types of protocols can impact our brain health and our longevity and

really excited to get your perspective on that. I think first, like, we hear, you know, kind of this concept or this phrase kind of mind-body connection a lot. I would love to know, like, you know, what does that phrase kind of mean to you as someone who studies both the brain and the body? It's funny because if we went back maybe 10 years, the way that neuroscientists would think about the brain versus the body is that they were these like two completely disconnected things that had almost nothing to do with one another. And luckily, you know, we've sort of gotten past that point and now we're really starting to appreciate how they affect one another. So people will often hear about the gut brain axis. You know, that's one that gets talked about a lot,

you know, the gut directly affected the brain and vice versa. With that comes a lot of complexity and we sort of are now in this arena where we know it's important, but a lot of the stuff we just, we're not really sure we understand it yet, which is great because that means that I get to keep working for a few decades and stay employed, which is nice. But. But, I think about it in sort of that mind-body connection, particularly when we're focusing on cognitive performance, brain health, I think about two main things. So the first being the obvious one, which is that physical activity has a direct impact on brain function. And then the other one is in the other direction where our brains can affect our performance and our physiology in

multiple ways. And that could be, you know, if we think something is going to be bad about our performance, we will perform worse. The belief effect. right it's usually negative unfortunately usually we can have this sort of like dampening effect or negative effect on our physiology and it's usually around stress and expectation expecting more from ourselves than we're currently giving that can have a negative impact on our on our health and physiology so it goes in both directions and it's like those are the two main buckets that I think about what I think of mind-body connection I love that okay so when we think about how to strengthen you know kind of the neural pathways you know we mentioned sleep you know maybe just you know hit

on the importance of sleep because I would imagine our brain health, it's kind of a lack of communication between these pathways. Correct me if I'm wrong. But, you know, sleep is going to improve how these connections communicate. Maybe if you can just kind of talk about the repercussions of kind of short, low quality sleep on the brain and kind of how that manifests in other areas of the life. I think it's useful to maybe give the framework of how I think about things that are necessary for brain health because then we can figure out, you know, where each piece fits into the puzzles. So in general, I think there are, you know, three main things that the brain needs. And the first is the supply of nutrients that are important for its function. And that's,

you know, oxygen, but then, you know, glucose or ketones, you know, lactate. All these can fuel your brain. And it needs to get to your brain in the first place. So you need good vascular function. You could go cardiovascular health. Your blood vessels need to be as healthy and flexible as possible. And that's important because of something called neurovascular coupling, which basically says that when an area of the brain is more active, it asks for more blood flow. More supply of these nutrients, but then your vascular system needs to be healthy in order to do that. So there's the supply. And then there's also, you know, the nutrients and things in the diet that would come through that

supply. Then there's also the demand itself, which is critical. You know, actually asking your brain to do things. Really important. And we know that any tissue in the body, if we stop using it, and I think muscles are one that people can really envision, right? If you don't go to the gym or you stop working out or you break a leg and it goes in a cast and you stop using it, those muscles are going to get smaller. And the brain is essentially exactly the same. If you stop using portions of the brain, you stop using your brain, it will say, hey, I'm not really needed here and it will start pairing back those connections. So we need to create demand. That's important. And then on the other side, we need to protect and support the

brain as it adapts to those stimuli. So there's probably two main components of that. And the first one is the absence of toxins or stresses that may inhibit that process. So we know there's a lot about air pollution that can certainly increase our risk of cognitive decline, you know, heavy metals, maybe metabolic disease, right? Sort of persistently high glucose levels, those seem to be problematic. So you're making sure there's like a safe environment. But equally, making sure there's time for rest and recovery. And so that's where sleep is really critical. And there's multiple parts of that, but it's important for giving the brain time to consolidate and strengthen those connections. Then also, sleep is when we clear waste out of the brain. And we generate a lot of

metabolic waste as we use our brain during the days. And that's where a lot of our sleep pressure comes from. These metabolites build up. And then that makes you sleepy so that you can clear them out. So multiple parts of sleep are really important. And, you know, particularly for that kind of recovery process. And I think, again, if I sort of put my neonatology hat on, people see this in babies. And I think that often helps them understand it. So you know that as a baby or an infant, a toddler starts to build its brain, the amount of interaction it has with the environment, like trying to climb things and failing and falling over. And it's the same with language. It's the same with social interaction. Like trying really hard, sort of pushing the boundaries of what's

currently capable and then sleeping a bunch, right, to try and, you know, consolidate all those things that were learned. And that doesn't change, right? Your brain always need that. It's just that we give it less opportunity to do so as we get older. So like thinking about how that brain develops first, I think sort of helps us picture why it could be really important. Perfect. You've co-authored some papers around, you know, circadian desynchronization. And, you know, it's an area that you know a whole lot about. A lot of my PhD work is centered around all things, kind of circadian. Just maybe as you kind of zero as you think about sleep in this framework maybe just talk a little bit about sleep consistency this is a metric that we measure on our loop app we give kind of a seven day average of

you know how your how your sleep consistency is and show that in kind of our weekly performance assessment so people can kind of see what the target is and where they fall where they fall inside or outside of that target it's really important we see this sleep consistency bubble up in all of our research as being kind of the single thing single behavior that's most predictive of mental and physical health resilience. So maybe just talk a little bit about how you think about that in the context of the brain and maybe inspire people to really try to move toward this behavior because it's so hard. It's like the hardest, I think, behavior for people to deploy, but it's actually probably

one of the most important. It's clear that it's very important. And there are maybe three main threads that I'd want to come out of that. So the first, there was a very nice study that was done with medical students a few years ago where they looked at the consistency and timing of their sleep as well as their dim light melatonin onset so so when as kind of like a marker of their usual bedtime when is their metatone is to start to increase give them an idea of maybe where their sleep is positioned within the 24 hour day and there were two things that they found the first was

that the later dim light melatonin onset was in general the worse the GPA of the students was so they're going to bed later more regularly um or we're going to bed later in general and then that was associated with slightly worse academic performance. Then the other one was sleep regularity. So how often are they going to bed at the same time every night? And again, the more regular their sleep, the better on average their grades were. So it seems that, you know,

having your sleep timed with darkness outside, as well as that being regular, both seems to be important for, you know, sort of daily in and out cognitive performance. There's one thing that comes out of that, which is one of the reasons that I think that's the case. And yes, sort of it being timed with our circadian biology, I think is important.

But another more practical aspect, I think, is that people who go to bed earlier and more regularly get more sleep opportunity, right? Because usually there's something in the morning that you have to get up for. And particularly if you're a student, these are medical students, you've got class, you're going to go and do pre, pre, pre, pre rounding at 4 a.m. or whatever. And so there's something that's going to wake you up the next morning. Like for me, it's my dogs. My dog is going to wake up at 6 a.m. regardless of when I go to bed. Okay. So I need to plan back. You know, if I want to get eight to nine hours of sleep opportunity, then that tells me when I need to go to bed. And so I think part of the benefit is around, you know, circadian entrainment and regularity. But I think part of it is also just total sleep opportunity. How much time are you getting in bed in order to sleep. And the third bit that I wanted to come out of that is that there are some nice data on sleep time. So it's not sleep quality, but it's time spent sleep and you can manipulate somebody's cognitive performance the next day by manipulating how long they think they slept, regardless of whether it's true or not. And so this is a fascinating

study. A whole bunch of studies in this vein have been done by Ellen Langer and her group at Harvard where they manipulate clock time and they do this in relation to blood sugar and they did one in relation to sleep where they had people in the lab sleep for five hours or eight hours, but they manipulated the clock so that when they woke up, they thought, thought they slept five or eight hours, but it crossed over, right? So there were some people who slept the amount of time and then knew that they slept that amount of time or thought they thought they'd slept the same amount of time that they did sleep, but then some were the other way around. So some slept for eight hours and thought they'd slept for five. And some

slept for five and thought they'd slept for eight. And in those groups, they saw that if you slept for five hours but were told you slept for eight, then they had no negative effect on their cognitive performance the next day. Whereas those who slept for eight, but were told they slept for five, it negatively affected their cognitive performance and how sleepy they felt. And why I think this is important here is because, yes, a regular bedtime, enough sleep opportunity. I think there's a really important. But I think if we get too worried about that, if we think, oh, my, I went to bed really late last night. And I didn't sleep properly. And now my brain is not going to function properly. We're going to tell ourselves that. And it's going to

be true. But probably not because we didn't sleep well. It's the stress that comes around it. So while some of these, what is clearly very important, I think it's also important to just, you know, realize that occasionally straying from that is not a big deal. You know, it's all about, you know, trends over time. Right. And there's no need to be perfect every day. You know, it's just kind of zooming out and looking at. Do we, if we even know what perfect is? Exactly. Yeah. I mean, it sounds like that's up for debate. But I do think that there are real impacts on the dopamine system when we're experiencing short sleep chronically. And I think that's been pretty well documented. But yeah, so, you know, I think the message is for sure one or two days

here or there over the course of, you know, a month is certainly not going to have a huge impact, but trying to be as good as you can be, I suppose, is potentially the path forward. But it sounds like there are a lot of open questions, which is, again, why we have jobs. We have to keep asking these questions and doing research. Cool. All right. I really appreciate the framework. I think that's important for people to have a model just to understand everything that kind of goes into brain health. Maybe just talk before we kind of dive deep into exercise and all the components they're in, maybe just talk a little bit about nutrition.

You kind of tapped on, you know, you talked briefly about glucose and its impact on the brain. Maybe just unpack, you know, kind of high level, like how should people think about about nutrients and the brain and, you know, what are some just maybe kind of broad advice that people can follow that, you know, will have a significant impact on cognitive functioning and just overall brain health. So if we start with individual nutrients, which is something that, you know, people have focused a lot on, I think there are several things that seem to be important. And again, whether you're

building your brain in the first place or trying to keep your brain as healthy as possible late into life. And, you know, people will have heard or thought about, you know, most of these several times before. So long chain omega-3 fatty acids, particularly DHA. It's critical for the brain, both brain development and long-term brain health. But there's an interaction and this has been discovered mainly in those at risk of cognitive decline dementia, there's an interaction with B vitamin status, which seems to be really important. So there were a couple of really important trials done in Oxford by David Smith and his team. And they looked at B vitamin replacement in those with high homocysteine levels who are at risk of cognitive decline. And

homocysteine is a nice blood marker of kind of one carb metabolism methylation status. You know, it's much more complicated than just one marker, but it's one that people can get access to. And in people who have high homocysteine levels, by giving them some B vitamins, B6, B12, folate, riboflavin, and you decrease that homocysteine, then you can slow brain atrophy and cognitive decline. And they showed that in this randomized controlled trial. However, they found that the impact mainly came from those who had adequate omega-3 status. And so you need both. You can't just have one or the other.

And we always like to boil it down to one or the other, but you can't. You need both. And the reason for that is if you're trying to get DHA into the membranes of the cells in your brain, which is where you want them to be, then they need to be part of phospholipids. And to generate those phospholipids, you need B vitamins and one carbon metabolism to construct them and attach those molecules together so that they can fit into a cell membrane. So B vitamin status and omega-3s are very important. And maybe just a quick laundry list of foods that kind of will help just so people can center around

if they're not into supplements or can't afford them, like what would be some foods they can buy that will help check off those boxes. Yeah. So your best bets that particularly if you're on a budget are going to be small, cold water, fatty fish, macrules, sardines, things like that for the omega-3s. I have a can of sardines a day. Great. That's going to be plenty for your DHA. And there's been a lot out there on, you know, fancier, a phospholipid type supplements for DHA.

and a colleague and I actually wrote a paper on why over, you know, if you look at DHA intake over time rather than a single pill, single study, it actually doesn't matter. So just eating a little bit of fish is plenty. And then, you know, if you want B vitamins in the most bi-available form, liver is your best bet. Plenty of B12 folate, riboflavin, you know, there are some people with, you know, a very small proportion of people who have a certain type of snip on their MTHFR gene, just. need a little bit more riboflavin. But all they need is the recommended daily allowance. They don't need, like, tons. They just need to eat some, and a little bit of liver will be great. So generally, organ meats or meats are better sources of bioavailable B vitamins. Of course, you can supplement if you want to, if you don't want to eat animal products. There are certainly

some people who choose that, and that's fine. You can definitely get them from certain supplements. Along with that, I think it's also very important to get enough coline. That's important for the metabolic health, particularly liver function preventing fatty liver, but then also, also for the brain, and then liver, eggs are great sources of that. There's a whole bunch of things. We could talk about supplements and nutrients forever, but one other thing because I think it's really important, particularly in relation to sleep and cognitive function, is creatine. I think everybody should take creatine. Like, I can't think of a single person who shouldn't unless maybe they're on dialysis for kidney dysfunction, maybe. And even then, I'm not even sure

that's true and I had to actually redo my blood panels because my kidney the yeah kidney function was like high and it's because I take creatine and didn't know because you take creatine yeah so that's the one thing you need to be mindful of is that your creatinine will go up if you take creatine but it's got nothing to do with your kidneys not working which is what people thought right and that's what if I was like oh my god your kidney's going to fail like any minute I'm like I don't think that's the case but yeah so actually for athletes you know I spend a lot of time looking at athlete blood tests, have a course on looking at, you know, how to interpret blood tests for athletes, I would essentially throw creatinine away as a marker for athletes. It's actually

a better marker of muscle mass than it is of kidney function in elite level athletes. If you want something instead, use cystatin C. It's easily available if you know how to ask for it. And that isn't affected by muscle mass or creatine intake. Related to that, I was bitten by a pit viper in the Costa Rican jungle a few years ago. Oh my goodness. And I was in hospital for 11 days in Costa Rica getting anti-venom and steroids and antibiotics and all that stuff. And they didn't want to discharge me because my creatinine was high. They thought my kidneys were failing. And I was like, I just have more muscle mass than your average patient. And I take creatine. Like I know why my creatin is high, but they almost didn't want to discharge me. So, so yeah, it's important to know

that that's the thing. But yeah, creatine for acute cognitive benefit, protection for the brain against concussion, it decreases depression symptoms in those, in randomized control trials. So like a whole bunch of stuff while creatine is good for the brain. That's my other nutrient that I'd focus on. That's great. That's good advice. I love it. All right, well, let's shift our focus to exercise. I'm super excited to dig into this. I think it's pretty well documented at this point that exercise is helpful for the brain. I think a lot of folks kind of think about when they exercise, it's, you know, they're trying to grow their muscles or they're trying to lose weight. And I think what is sometimes less visible or difficult to perceive is the impact that it's having on the

brain. But clearly all of these things are integrated and, you know, kind of work together. So maybe just talk high level. And then we'll kind of dig into specifics, just how movement in general. And, you know, I think people, you know, think about strength training, but, you know, just walking, you know, how just general movement really influences the brain. Yeah. There have been a number are ways that people have it to this and there are actually several randomized control trials in older population showing that different types of physical activity can have, you know, amazing benefits to the brain. And so the first time the study was about eight years ago now, the first time that we ever saw in adult or older humans that certain parts of the brain

could get bigger, as in you do an MRI scan, you do an intervention in an area of the brain gets bigger is was with exercise you know before then we basically thought that the brain was fixed and then just got smaller and worse over time and there was nothing you could do about it so volume so this is volume so it doesn't tell us about cells like have you grown new neurons you can't really tell that on an MRI scan but what they did was they took individuals in their 60s and 70s and they randomized them either to 40 minutes of brisk walking a day or 40 minutes of stretching in the control route and then they did this for a year and what they found was that in the group that did brisk walking for 40 minutes three times a week there was an

increase in size of their hippocampi which is an area of the brain that's that's critical for memory and is also an area of the brain that we start to lose or atrophies as we get dementia and certain types of Alzheimer's disease so that was reversed in those who just did brisk walking and the what they correlated with that was there was a bigger increase in those who improved their VO2 Max more. So the fitter they got, the bigger the hippocamp I got. And that was, seemed to be related to the amount of BDNF that was released during exercise, BDF being brain-derived neurotrophic factor, which supports, you know, supports brain health and function. So that was, you know, in older individuals, you know, who were sort of at the period of time when, you know,

we're starting to see measurable cognitive decline, you can reverse some of those structural changes in the brain with just brisk walking three times a week. which is amazing. That's incredible. So is this by forming new synapsis? So the answer is we don't know in that study. All we know is that hippocampa got bigger. But there's a whole bunch of stuff that goes into how big an area of the brain is. So we think about neurons. But the majority of the cells in the brain are other types of cells that we call glia and includes microglia, oligodendro glia or oligendrocytes. Those are the ones that have the white matter. and then astrocytes or astroclia as well.

So there's a whole bunch of supporting cells that we know proliferate and change at any time. And then there's also, you know, all the stuff that's between the cells, the extracellular matrix, right? So, you know, you've sort of built up proteins and structure around those cells and all of that can contribute to more volume.

So we know the volume got bigger and that was the first time we've seen that in adult humans in a sort of well-controlled study. But what exactly makes up that volume? We're not sure. But, you know, that seems to be associated with better function, which is what we really care about. Wow, that's incredible.

You know, I was doing some research, and I just saw that how much time folks spend endure and how much time people spend sitting. And, you know, just how that's increased over the course of the last, you know, two decades. I mean, it's really problematic, right? So advice to improve the brain, just get out, brisk walk. How much time do you think that a person needs to walk briskly in order to see these effects on the brain in terms of just absorbing information better and kind of forming long-term memories and the things that we want to be able to do.

So there was a recent meta-regression that tried to answer this question, which basically looked at all the exercise studies and said, how much time per day do you need to exercise, you know, to get like a measurable, like a clinically measurable important benefit to preventing cognitive decline or improving cognitive function? And the answer is 30 minutes of moderate to vigorous physical activity per day. It's basically like government guidelines. Like that's enough to create like clinically important improvements in cognitive function.

And so I think that's great because I think it's pretty empowering. Like it doesn't have to be hours and hours every day, right? 30 minutes of brisk walking per day and you're right, you're right there. Like significant clinically important benefits to the brain can be seen with just that. And it doesn't have to be brisk walking, right? It can be, it's 700 met minutes per week. So you can, like, depending on the intensity of the exercise, you can dial that up and down, right? Would you want to go to do five minutes of sprinting rather than 30 minutes of brisk walking?

Great. You know, if you want to do 20 minutes of swimming, fine. Like, so you can, you can probably pick and choose. Like, for the really the core benefits, you know, anything in that range is going to get you there. All right. And just explain that real quick because people might not be familiar with that term. but I love that as a way to kind of quantify the work over the course of the week and how many met hours am I getting? I love that. Yeah. Yeah. So it's basically metabolic equivalence

and it's this idea of integrating or to give you an idea of intensity and then you do like intensity over time. So there's a standardized list which is you can download as if you look up like the international definition of met's for exercise, then. you'll download a PDF that, I mean, I think last time I was it was like a hundred pages long. And it's like got every single like household activity, gardening activity, all the different types of stairwalking at different intensities and walking at different intensities. So like you can really, I mean, the problem is that what's, you know, if you and I did the same activity, you know, based on height and body weight and stuff, your METs are going to be different.

But it kind of gives you a rough idea of where you're going to be. Yeah. And there, you know, in terms in, in addition to memory, you know, reduction in stress, you know, which obviously impacts the brain as well, maybe just talk through kind of how just even these low levels of activity are going to stimulate the release of endorphins and act on the opiate receptors and maybe just kind of break down what's happening and how that actually can reduce feelings of anxiety and depression. I've worked with a lot of, you know, high performance, high performance. And that's sort of elite level athletes, but also elite level knowledge workers,

if we can call them that, who also have like a sideline in physical activity. So that, you know, it's very common to, to have a high-stressed job and then also want to be, you know, an elite-level master's triathlete on the side. Like that's somebody, that's the type of person I've done a lot of work with. And so there are a large number of, again, you know, randomized controlled trials that show that physical activity decreases feelings of stress and anxiety. We can talk about the different neurotransmitters but I'm not sure that really changes anything like we know that it we know that it works that's an important part of it and again you know within the same parameters that we're talking about right in terms of in terms of the amount so so those same you know volumes and intensities of exercise you know

700 minutes per week whatever half an hour of brisk walking a day right that that's enough to have a significant improvement on on stress and anxiety the other side of that and I guess this is where my mind immediately goes to because this is what I've seen a lot a lot of of is that often people are using exercise as like a catharsis to ignore something else that is happening in their lives. So I always like hang that little caveat on there. And that seems to be very common. And so while for the general population at a population level, physical activity dramatically decreases stress, oppressive symptoms, anxiety symptoms, are incredibly important. In sort of like the niche high performers, it can have, I think it can have the opposite

it effect over time. Yes, you feel better, you know, endorphin release, modulating the end cannabinoid system, like all this stuff in the moment absolutely makes you feel better. But it may come at the cost of running away from something else. So individuals with, you know, they're working 60 to 80 hour work weeks plus 20 hours a week of training and then they're going to travel to an international Ironman triathlon three times, three times a year. Like what's going to happen is you're going to get divorced. I know those people. Yeah, right?

So the first thing that you're going to be, you're going to get divorced and then you're going to be estranged from your family. And, you know, long term, that effect on your mental health and cognitive function is going to be far worse than any sort of benefit you're getting in the moment. So, like, balance is also really critical. Yeah. And that's, you know, obviously we think a whole lot about that at whoop, you know, and that's the whole concept of recovery, right?

is really understanding, you know, how your body is responding and adapting objectively to the intensity and the load that you're putting on it and not just cardiovascular training load, but also just the life load, you know, that comes with having a job and a family and all the other things. So, yeah, I think achieving that balance is obviously critical. And I know we love that we can quantify that, you know, to a degree. And I think that allows you to understand how do you actually pull back and include, you know, bring in a bit more balance, you know, and more recovery. And maybe along those lines, you know, what type of recovery modalities are the most effective at, or are there any studies that point to certain recovery modalities that impact the brain?

Like a huge fan of cold immersion and sauna and maybe just talk about some of the recovery modalities that have a sympathetic effect in the short term, but actually really have this longer kind of parasynthetic tail. So for recovery and the brain, it's kind of tricky mainly because the studies that we have on those things and long-term cognitive function, cognitive decline, they're observational and epidemiological and there's probably some residual confounding. So the best example I have of that is sauna use in Finland, you know, and everybody quotes these studies, you know, decreased risk of cardiovascular disease, Alzheimer's disease. But like the effect size, like how much benefit you get,

you know, if you're going in the sauna five times a week, is so large on cardiovascular disease, for instance, that there has to be some what we call a residual confounder, which is like there's something else that's different about those people that's contributed to that. I'm not saying that sauna won't decrease your risk of cardiovascular disease. I think there's a number of reasons why sauna could and would

be beneficial, but there's like, there's something else, like, and this is the problem with epidemiology is you can never know the things that you didn't account for, right? So until there's some trials there, it's difficult to know. So I'm a big fan of sauna. I, you know, half my family is Icelandic. We love a

sauna like don't get me wrong sorens are great but some of that we just have to acknowledge that some of that data is kind of missing so you also mention cold immersion uh there's two parts of of cold water immersion that seem to be important the first one is the pressure effect seems to be important particularly for you know lower limb and muscular recovery you're being in deep enough water and getting enough pressure this is this is probably contributing to sort of you know some lymphatic flow and things like that that seems to be beneficial and there are some studies that sort of tease that out in the recovery sphere. But we also know that when you're exposed to a lot of cold, you stimulate the release of a number of things are actually very similar to exercise, but then,

you know, you create this acute stress that then down modulates stress over time. And you can do that without the total load, like the same load on the body, if that makes sense. So you can stimulate some of these processes without having to stress the body as much in the same way. And so I think that's definitely very interesting. And, you know, how you play around with these things, I think is important. You know, there's some signal of like when you time, cold exposure or after exercise may, you know, have some effect on your, on your response to the exercise itself. And I think that probably matters if you're an elite level athlete. It probably matters less if you're just like somebody who's trying to be fit and healthy as possible. Yeah. So let's dig into

to exercise like really specifically and try to get specific. So if you were to create a taxonomy of the effective to least effective exercises to maximize cognitive functioning in brain health, what would that be? Like, where would someone start? Yeah, a combination. So, so again, I think if we, if we think about, you know, two portions of the framework that I talked about, one is, you know, vascular, vascular supply, but then also, you know, some of the things that get released during exercise, so like BD and F, which supports brain function. So one part of that, you know, we've seen in the study that I mentioned before, but also in multiple other studies, even like on a day-to-day basis, your memory is better if your V-O-2 max is higher, on average at a population

level. So the fitter you can get cardiovascularly, that's like the vascular function component, but also all those other things to get released at the same time. So that's one bucket. And then there's also the neuromuscular stimulus, like how the movement stimulates the brain itself by forcing it to create new connections. And so in people who haven't done much strength training, then even just like basic resistance exercise does that. And there was the smart study that they did in individuals in the 70s. It was three times a week, six exercises, three sets of eight, you know, just like standard, standard bodybuilding, using machines. You can do it in planet fitness.

Like that was enough to stimulate these connections. And again, they did brain scans and then some cognitive performance measures in people in their 70s. So, like, if that's the kind of resistance training that you need, that you get benefit from, particularly if you're somebody who hasn't done much resistance exercise. However, if you're only going to do one type of exercise for brain health or preventing cognitive decline or improving cognitive function, the most important thing seems to be from a bunch of meta-analys is a type of exercise that includes a coordination component. And basically that means anything that challenges your orientation in space.

So this could be, and usually if you're doing one of these things, you're going to be working other areas as well. But basically we're talking things like ball sports, yoga, slacklining, skateboarding. You know, anything that challenges you from a coordination standpoint seems to have the biggest effect size on congregative function. That's even if you're dancing, I think particularly as people get older, there are more and more studies on dancing in older adults. And I think, you know, there's a social component, there's a cardiovascular component,

there's a coordination component, there's often a music component, which seems to really beneficial for the brain. So like you've ticked all these boxes. And so dance classes, when they compare the effect of dance on the brain, and again, like doing multiple brain scans and cognitive function, to some other form of exercise that has the same amount of effort and either with like circuit training or running, there's a bigger benefit from dance, probably because of the coordination component, but maybe some of those other things as well, like social

interaction and stuff like that. So dance seems to be the one that like kind of ticks as many boxes as possible. Wow, I love it. That's definitely not what I was expecting you to say. So this is, hopefully this is really exciting for folks. Like, shoot, I'm going to just sign up for dance class. I love that. Very cool. So why don't we talked a little bit about just kind of low level cardiovascular, just risk walking. Maybe let's talk a little bit about strength training and what the data show there. I know there's been some really good studies on resistance exercise and how it kind of has this protective effect and hippocannibal plasticity and all sorts of cool things. But I would love for you to break that down for us. Yeah. So again, there's broadly two kinds of

studies that we look at. So one being these randomized controlled trials, these interventions where we can really control everything that's going on. And the other ones are these sort of epidemiological studies. And there's, you know, a number of epidemiological studies where you just ask people, how much resistance training do you do? And usually it's a mix. So if the data come from something like N. Haynes, which is the National Health and Nutrition Examination Survey that's done a different cohort of people in the U.S. every year, they're supposed to be sort of representative of the general population. And you look at the questions they have about exercise. You know, the resistance training ones are usually around how much heavy load you carry at

work and then like do you do calisthenics like pushups and squats and things like that at home it's not like are you a power lifter so we kind of have to take into account how people ask about the resistance training questions in those things but you know with that said a number of epidemiological studies have suggested that those who do resistance training and I think like the the maximum benefit seems to around one to two times per week and then beyond that like more isn't necessarily really better, it seems to be associated with, you know, a decreased risk of dementia and cognitive decline. On the other side, we have the randomized control trials. So I think the best one that's been done in an older population, which is usually where you're going to pick up

some of these things, is the smart study that we already talked about. But then, again, there have been meta-analyses of multiple studies where they do something similar. So like two to three times per week, 45 to 60 minutes a time, six to eight exercises, eight to 12 reps, like sort of that kind of approach. Significantly, particularly seems to improve white matter connectivity, so in the brain, which, so if people are thinking about the structure of the brain, on the outside, you have gray matter, the cortex, which is probably what most people think about when they think about the brain. and then below that there's, you know, through a lot of the brain, there's this layer of white matter,

which is neurons that have these sheaths around them that allow for very fast conduction of messages. And this is between areas of the brain and then between the brain and the rest of the body. It's where all the relay signaling happens. And this is the area of the brain that's, you know, one of the areas of the brain that's really sort of expanded in humans relative to other species. And white matter connectivity seems to be particularly strengthened with resistance training. That's the most consistent signal across all the randomized control. trials, including the smart study and some of these other ones. When you think about the hippocampus,

which we talked about earlier, which is an area of gray matter primarily and very important for memory function, then I think overall things like aerobic exercise seem to have more of a benefit on the hippocampus plus an additional benefit of that coordination component. So again, in those dance studies, the hippocampi grew more in the dance group compared to the circuit training group, even though the aerobic component was the same. So, you know, some combination of aerobic training plus coordination plus resistance training is probably going to give you the balance of those things. So all the different areas are going to get hit and then like the connectivity between them.

And so that will kind of give you the global effects that we think we want. Do you think that like eventually that will be like standard part of like dementia risk reduction strategies? Like are we getting to a place where doctors are aware of this and they're like almost prescribing that? You know, like for, you know, for individuals who are at risk of Alzheimer's, for example, and, you know, a lot of us fall into that category, right? You know, where we might be vulnerable to that. Yeah, just curious what the state of things are. I hope so.

I certainly, you know, when you look at late onset Alzheimer's disease or late on or age-related dementia, which is what most people are worried about when they think about their cognitive function, right? There's a small sliver of Alzheimer's disease, less than 5% that's genetic, probably hard to do a lot about that. But the vast bulk of dementia is directly related to lifestyle and the environment. Like almost all of that risk is potentially modifiable. And there have been some great trials, things like the finger study that came out a couple of years ago, where they did this. They improved people's diet. They improved their exercise.

There was a stress reduction component and there was a cognitive training component. I think they did some kind of online brain training, which is better than nothing. And they saw significant improvements in cognitive function. And so there are lots of these pockets now turning up. How you scale that, I don't necessarily know the answer to that yet, as well as how are you going to pay for it. So it's going to be much easier in nationalised healthcare systems like the UK and in Scandinavia where I think doctors are prescribing gym memberships to individuals. Like that's definitely something that's happening yet. Harder in the US healthcare system, but I certainly hope that that's somewhere that we're heading towards.

Yeah. Would you say that just increasing muscle. mass would be a great place for folks to start. So yes, I absolutely do think that. And there are two studies that it makes me think of. So in the first one, they looked at how much brain is inside somebody's skull. And so people have different sized skulls, but you want basically as much brain inside that skull as you can get, right? Because as you start to lose brain, that's when things start, that's when things are going wrong. And so they looked at like the total volume of the skull that was taken up by brain on a brain scan. Then they looked at body composition measures.

They found that total muscle mass was the best predictor of how much brain you have inside your skull, which I thought was very interesting. And that was across people both with and without dementia. And other things that you might think were important were less important. So BMI didn't predict it, neither did fat mass at all. So muscle mass seemed to be the important thing. Similarly, there was a study from the UK Biobank where they looked at a type of IQ test that they did for everybody in the UK Biobank, and it looked at fluid intelligence was the type of the test. And then again, they looked at all these different predictors of body composition and performance on this test. And muscle mass, again, was the best

predictor. And it was actually more important than women than it was in men. And in general, women have less muscle than men do, just to start with, on average, for a given size. They also looked at, you know, visceral adipose tissue, subcontaneous adipose tissue, BMI, all those things. Muscle mass was the best predictor. And that's probably for multiple reasons. Right. So when you're training to improve your muscle mass or you're doing things that maintain or improve your muscle mass, right, there's the stimulus itself, which is obviously creating direct, you know, demand in the brain. There's the things that get released while you exercise. There's also a little bit of the fact that, you know, if you're out there in the world

interacting with things and others, you're probably getting more social stimulus because that's required. And then on the other side of all of this, one thing that we haven't really talked about is that being sedentary, like not moving, is an active pro-inflammatory state. So it's not just the exercise is good. It's the removal of being sedentary, which is actively bad for one of a better word. So there's two sides of it. And I think people who are more sedentary, more of the time, it creates this sort of insulin-resistant pro-inflammatory state that we can mitigate through movement as well as the additional benefits from movement. And to kind of control for this, you know, I recently was listening to a talk by somebody called Dr. House, who is himself

is wheelchair-bound after a skiing accident. And so he's spent all this time learning about metabolic health in relation to those who have some kind of reduced movement for whatever reason. And those muscles, they atrophy and they become sort of pro-inflammatory and insulin resistant and that affects your entire body. And so this is not like me just being against people who sit on the couch. Like there are specific conditions where this is sort of more nicely detailed. And it really seems that muscle that is not active sort of creates this systemic effect throughout the body that can have negative effects. Gosh, that's incredible. So in these studies, do they identify, you know, what that ratio is, like what the proportion of time

you need to be kind of moving as opposed to, you know, sedentary? Like what, do you have a sense? so everybody you know there've been multiple ways that people have tried to unpick this and i think it's it's really important to start by saying that if you spend a lot of times you know sitting or sedentary because of your job or whatever i don't think that's something to like worry about too much i think you know what what really becomes important are like even just frequent small bouts of movement so there's this nice idea of movement snacks that that's come out there was some canadian in researchers, I think, who first mentioned it. And it's been used in the setting of individuals with some kind of metabolic disease. And so if you compare getting up and moving around for five

minutes once an hour, once every two hours to smushing together all those five minutes and doing it for an hour later in the day, you get more benefit just from like frequently, you know, just getting up and moving around. So I think it's just not being in the same position all the time that that's important. So just even just occasionally getting up and moving around. The internet exploded with this recent study where people did seated calf raises. I mean, they did four hours of seated calf raises. It was a lot. But then also, like, the effect on metabolic health was more than probably people expected. So you don't have to do four hours of car raises. But even just those small amounts of movement, and actually what they did

show was that the calf raises they did created like a metabolic demand equivalent of just going for a bit of a walk. So I would just go for a bit of a walk. if you can get outside and that kind of stuff. But if you can't, do some calf raises. But the idea is just that moving small muscles for small amounts of time can have a significant effect. I love movement snacks. That's awesome.

Yeah. And I think people kind of understand that, right? Just get up and move around a bit. There was a recent study that looked at this interaction between how much sedent through time you have versus how much activity time. And, you know, if you're getting the kind of activity that we talked about early, 30 to 60 minutes a day, I think you're going to offset, you know, the majority of any sort of problematic sedentary time, especially if like your sedentary time is broken up by sort of moving

around. So again, nothing particularly heroic is needed, but, you know, just some, some conscious effort to get that, those sort of like baseline amounts of movement in is probably going to be more than enough for most people. Awesome. That's amazing. Yeah, I think, you know, work from home has made, I think probably contributed a lot to the problem of, you know, because you could literally go eight hours. without getting up. You know, at least when you're in the office, you know, you go and grab a drink like you. But, you know, hopefully we're kind of coming out of that, you know, people working home from a while now and have kind of a setup that and are more, maybe a little more conscious of the fact that they're sitting for really long periods of time and needing to break

that up. But I think it's a really good reminder. And I think it's, and the data are pretty compelling on just how dangerous, you know, sitting can be to your point from an implementation perspective. So yeah, I think that's really helpful. Tommy, well, thank you so much for the discussion today. Where is the best place for folks to find you and to follow your work and just all the insights that you have on all things, kind of wellness and longevity? First of all, thanks so much for having me. I really, really enjoyed this. This is really great. I think Instagram is probably the best place to find me at Dr. Tommy Wood on Instagram. It'll be a mix of, you know, podcasts when podcasts come out, you know, pictures of my dogs.

That's probably most of what it is, actually. So if you enjoy a few pictures from the gym, some podcasts and some pictures of boxes, then Dr. Tommy Wood, that's the place to find me on Instagram. Perfect. Awesome. Well, thank you so much. And looking for, hopefully get to chat again, at some point, I'd love to continue the conversation. Lots more here. Yeah, likewise. Absolutely. Absolutely. Thank you very much. Big thank you to Dr. Tommy Wood for joining the show today to share his insights on strength training and brain health. If you enjoyed this episode of the Wooop podcast, please leave us a rating or review. Subscribe to the WOOP podcast. Check us out on social at Woop at Will Ahmed. If you have a question you want to see answered on the podcast, email us. Podcast at Woop.com.

Call us 508, 443-4952. A reminder, use the code Will. Get a $60 credit on Woop accessories. And that's a wrap. Happy holidays, folks. I hope it's a great one. Stay healthy. Stay in the green. And we will be back next week. Thank you.