The Diary Of A CEO with Steven Bartlett - Anti-Aging Expert (Peter Attia): Anti-aging Cure No One Talks About! 50% Chance You’ll Die In A Year If This Happens! Boost Testosterone Naturally Without TRT!

Episode Date: April 7, 2025

Dr. Peter Attia is a physician, researcher, and best-selling author of Outlive: The Science and Art of Longevity. He founded Early Medical, a longevity-focused practice, and co-founded 10 Squared, a hybrid testing lab and training center. In this episode, Peter and Steven dive into the real science of aging, the #1 predictor of mortality most people ignore, the silent epidemic of male loneliness and addiction, and how to boost testosterone and extend your healthspan naturally. Chapters: 00:00 Intro 00:02:16 What Is Peter Focused On at the Moment? 00:06:50 What Steven Wants To Be Able To Do in His Last Decade 00:10:20 Ageing Is Inevitable 00:15:15 What Peter Wishes Someone Had Told Him in His 30s 00:17:13 Men's Health 00:17:59 What Is It To Be a Man? 00:18:46 Is Testosterone on the Decline? 00:23:31 Sleep and Bad Choices 00:26:50 What Are the Things Peter Wants To Do in His Marginal Decade? 00:28:48 How To Prepare Now for the Marginal Decade 00:32:11 Peter's Workout Routine 00:35:39 What Causes Injury in the Gym? 00:37:45 Why Is Building Muscle Mass Important? 00:38:27 Training on Fatigue 00:40:43 Grip Strength Test as a Longevity Indicator 00:42:44 Danger of Falling After Age 65 00:45:32 How To Train Power To Prevent Falling in Older Age 00:46:46 Is Training Balance Important? 00:47:46 Peter's Approach to Flexibility Training 00:52:04 Peter's Strength Training Routine 00:53:06 Why Endurance Exercises Are Gaining Popularity 00:53:58 What Is VO2 Max and Why It Matters for Longevity 01:03:59 Jack's VO2 Max Results 01:05:40 Jack's Heart Rate Recovery Results 01:06:31 Jack's Zone 2 Test Results 01:08:34 How Can Jack Improve His Results? 01:09:00 Ads 01:11:18 Jack's Cardio Routine 01:13:21 Measuring Bone Density and Muscle Mass – DEXA Scan 01:19:52 Preventing Bone Density Loss 01:21:32 Nutrition for Bone Density 01:23:44 Building Muscle Mass 01:25:30 Gaining Muscle Mass Through Nutrition 01:27:26 How Different Are Women's Results Generally? 01:28:34 Determining if Subcutaneous Fat Is an Issue 01:29:52 What Causes Visceral Fat? 01:30:59 Intermittent Fasting To Reduce Visceral Fat 01:31:28 Sleep, Stress, and Visceral Fat Connection 01:32:34 Is Alcohol Acceptable from a Health Perspective? 01:36:24 Are People Electrolyte Deficient? 01:37:56 Importance of Nuance in Navigating Information 01:42:21 Peter's Book 01:44:13 Question From the Previous Guest 02:03:12 The Importance of Dopamine 02:07:27 What Is Peter Concerned About for His Kids? 02:09:24 Peter's Thoughts on Young People's Emotional Health 02:11:24 The Most Important Thing Peter Did for His Emotional Health 02:13:23 How Did Peter Know He Hit Rock Bottom? 02:16:07 Clues Someone Is Nearing Rock Bottom 02:23:48 The Roots of Peter's Addiction 02:25:48 How Has Therapy Changed You? 02:27:37 Can Emotional Health Be Fixed? Follow Dr. Peter: Instagram: https://g2ul0.app.link/CABLVLhrgSb Podcast: https://g2ul0.app.link/aKZjQEmrgSb Early Medical: https://g2ul0.app.link/42mSperrgSb 10 Squared: https://g2ul0.app.link/YOtJ2furgSb Article on alcohol: https://g2ul0.app.link/fK6HL1StiSb Buy Outlive: https://g2ul0.app.link/MXsH4WCrgSb More from DOAC: Watch on YouTube: https://g2ul0.app.link/DOACEpisodes Buy 'The 33 Laws Of Business & Life': https://g2ul0.app.link/DOACBook Get the Conversation Cards: https://g2ul0.app.link/f31dsUttKKb Newsletter Signup: https://bit.ly/diary-of-a-ceo-yt 100 CEOs Newsletter: https://bit.ly/100-ceos-newsletter Follow Steven: https://g2ul0.app.link/gnGqL4IsKKb Sponsors: Fiverr: https://fiverr.com/diary (Code: DOAC) ZOE: http://joinzoe.com (Code: BARTLETT10) Learn more about your ad choices. Visit megaphone.fm/adchoices

Death is inevitable, but the rate of decline is very much up to us. The drawback that young people have is they only begin to realize the inevitability of the decline when it besets them. So your team that came in for testing that are in their 20s, when I'm looking at these results, there were issues that were uncovered that were a concern, and ignoring it doesn't lead to a good outcome when you're 65. But a lot of people have this issue, so it's okay to speak freely about this. Yep. The biggest concern is that Dr. Peter Atiyah is the go-to physician for high performers,

celebrities, and anyone serious about unlocking the science behind a longer, stronger, and healthier life. I had a big epiphany at a funeral of a friend of mine who I realized had declined so much during their last decade that when they couldn't do those things that gave them pleasure because of injuries, ach and pains they weren't enjoying life. I call it the marginal decade. Wow okay so what are the most important parts of my health that I should be thinking about for longevity? So there's muscle mass,

muscle strength but we don't have a single metric that we can measure that better predicts how long they will live than how high their VO2 maxes which is a maximum amount of oxygen you can consume. And if you compare somebody who is in the top 2% to someone who is in the bottom 25%, there is a 400% difference in their all-cause mortality over the coming year. But how do I know if it's an issue or not?

We'll go into much more detail around that, but the way to avoid this is to train specifically for that marginal decade. And there's so many things that we just do wrong. The sooner you start, the better. So rule number one. I find it incredibly fascinating that when we look at the back end of Spotify and Apple and our audio channels, the majority of people that watch this podcast haven't yet hit the follow button or the subscribe button. Wherever you're listening to this, I would like to make a deal with you. If you could do me a huge favour and hit that subscribe

button, I will work tirelessly from now until forever to make the show better and better and better and better. I can't tell you how much it helps when you hit that subscribe button. The show gets bigger, which means we can expand the production, bring in all the guests you want to see and continue to doing this thing we love. If you could do me that small favour and hit the follow button, wherever you're listening to this, that would mean the world to me. That is the only favor I will ever ask you. Thank you so much for your time.

Back to this episode. Dr. Peter Rittier, what is keeping you busy at the moment in terms of the subjects that you wrote about in Outlive, but the work that you do online and the work you do in the variety of businesses that you have, what is keeping you fascinated at the moment? What is one's mind focus on? I wish I could say one thing. There's probably a few things and maybe that's not good.

Maybe the most successful people in life only think about one thing. I would say one of the things I'm thinking a lot about is how to translate outlive into a delivery system, obviously digitally, that basically operationalizes what is in that book in a manner that allows people to, with as little friction as possible, implement the solutions for themselves. So basically, how do you live a longer life? How do you age as gracefully as possible and maximize your health span? I think the other thing I'm focused on that is related to that, of course, but distinct, which I know your team got to participate in a little bit this week was kind of how to train people for their marginal decade, right?

So this idea of we're all going to have a last decade of life. I call it the marginal decade just so that we can get comfortable talking about something that people don't like to think about. And I'm convinced that ignoring it and not thinking about it doesn't lead to a good outcome. Instead, if you prepare for it and train for it, like an athlete trains and prepares for their sport, you'll have the best version of that possible. Marginal decades and centenarian decathlon, did I say that correctly?

Centenarian decathlon. Centenarian decathlon. Can you explain these two terms to me? Yep. So the marginal decade is the last decade of life. Last decade of life. Again, it's this weird thing where most people don't know the day they've entered it, but most people also realize at some point when they're in it. I thought a lot about it.

This was sort of a big epiphany that I had in 2018 when I was sitting in the church at a funeral of the parent of a friend of mine who I realized had declined so much during the last decade of their life that even though they were alive, they weren't enjoying life. The things that they loved to do, in the case of this individual, play golf and tend to the garden, they couldn't do. They just physically couldn't do it. They had injuries, they had aches and pains. And when they couldn't do those things that gave them pleasure, they retreated from life.

And I don't think there's a person listening to us who can't appreciate that because they've witnessed it. They've seen it in a parent, a grandparent, a loved one. And I don't know, there was just something about that moment, which is often the case, right? It's usually like years and years of thinking about something and it crystallizes in an instant. But in that moment, I realized, aha, the way to avoid this is to train specifically for

that decade. And the best model for how to do that is to look at athletes, because every athlete trains with specificity. So think of like all the different types of athletes you would know. So if you think about like a sprinter or a basketball player or a football player, they are so different. And very little of their training looks like the other guy. And the reason for that is they're doing something very specific.

The sprinter has a goal, which is to move 100 meters as fast as possible. That's it. And that requires a certain set of skills. And the footballer has a totally different goal. Yes, he has to be able to run fast for short distances. But just being able to run fast would not produce superior results. And then the basketball player would be different. And then the skier would have a totally different set of skills.

So I said, well, who's the most well-rounded athlete out there? It's the decathlete, because that guy's got to do 10 different things really well. Now he or she doesn't have to be the best in the world at those 10. In fact, they never are. But overall, they're considered the best athlete because of the diversity and breadth of what they can do. And so I said, that is our model. So what is the centenarian decathlon then is I say to you, Stephen, one day you are

going to be in your marginal decade. What do you want to be able to do physically, athletically in that last decade? The answer is so clear to me because it's associated with all the things that make me happy. So it would be being able to explore the world still with my partner, my romantic partner. But I would even dig further. Tell me what that looks like okay, so I went to Bali mm-hmm and Me and my girlfriend wanted to go whitewater rafting and to get down to the whitewater rafts in Bali

We had to walk down and then up again. Mm-hmm about a hundred meters of stairs And as I went down those stairs I had one of those moments that it sounds like you had at the funeral where I realized that my dad could not walk down These stairs he couldn not walk down these Stairs he couldn't walk down them and he couldn't walk up them. And by the way, it's a different reason I'm gonna point this out and I want to come back to your story Walking down is not about endurance walking down is about eccentric strength in the quads to be able to Decelerate the body as it's moving down very important coming up is about concentric strength in the quads and glutes and endurance.

All right, but continue. That's a really good point because they're two different training systems. And then the reason why that was so important was because of the great time I had in the white water raft with my girlfriend. So going down that lake through Bali and I thought, gosh, if I hadn't, if I'm not careful and I don't think about this, I won't be able to have these experiences when I'm 60. What was involved in being in the raft? Yeah, so a lot of strength required to like row to keep us away from the rocks, to push

us off when we got stuck, fall in the water, get it back in the boat. Think about the scapular stability that's required. Think about the upper body strength you need to lift yourself back into a boat if you fall. I mean, the list goes on and on and on. And it took a long time. We were out there for two hours going through this lake. So the other thing I think about is Christmas.

And I think about my nieces. And my brother's a year older than me, and he has three kids under the age of six. And you know what that's like. These kids just sprint off in every direction. And they'll say to my dad, they'll say, come and play in the garden. And my dad wouldn't be able to play with them in the garden the way that they would want to play in the garden running around and being chased around. So my dad just watches them from the kitchen. And so these are just obviously all the emotional things come to mind first,

because those are the things that stay with us. And I'll give you one more. The other thing that comes to mind as a man is just being able to protect my family. And I don't necessarily mean wrestle and intruder, but I mean like lift things. And if something falls, being able to pick it up and move it. So those are the things that come to mind first and foremost. It's protection, it's memories, it's activities that create relationships and connection. That's exactly the exercise we do.

We take people through, give us the 10 most important things you want to be able to do. So if you start with, I want to be able to go back to Bali, and I want to be able to go down those 100 stairs, get in the raft, go down the river, come back up the stairs. That gets broken down into very specific movement patterns. Playing football with the kids out back gets broken down into very specific movement patterns. By the way, they're very different.

That one comes down much more to foot reactivity, lateral movement, things like that. Being able to pick something up off the floor is yet another set of movement patterns. It turns out there are approximately 27 physical requirements that are necessary to do the sum total of most things people want to do. Part of the reason why I think people don't care enough is because they see aging as inevitable. So they look at their parents, their grandparents and go, they're immobile, they can't function properly, that's my destiny, it's genetic. Obviously I don't agree with that, though I have tremendous empathy for people who might

feel that way. When you see something as ubiquitous as the decline of untold numbers of people as they age, it would be very easy and tempting to say that that is the inevitability of our species. Death is inevitable, despite what some of decline is very much up to us. The preservation of strength, stamina, movement capacity, those things are largely up to us. In fact, there are actual data that demonstrate quite clearly, in fact I was just reading a paper yesterday in the journal Cell that looked at the role of exercise in aging individuals to preserve mitochondrial function.

So this is a study that looked at older individuals and it randomized one group to a significant amount of exercise and the other group was just sort of business as usual being largely sedentary. And then using pretty elaborate techniques where you biopsy the muscle, they look at the mitochondria, which are the kind of the powerhouse of the cell in these individuals. And it turned out that in the people who were exercising, there was very little decline in the mitochondrial function compared to what happened in the people who were not exercising. Now just because your mitochondria continue to function well doesn't mean all aspects of aging are offset, but it's a very important one to demonstrate.

And this is also true by the way of strength and endurance. There's a big difference in the rate of decline of muscle mass, muscle strength, and cardiopulmonary fitness in people who exercise versus who don't. So it's all kind of a long-winded way of saying you have as an individual so much more under your control than you realize, but you have to sort of begin to compounding the gains. I'll do it when I'm 50. Well look, the good news is 50 isn't too old. And I've met many people who don't begin to do this until they're 50. Well, look, the good news is 50 isn't too old.

And I've met many people who don't begin to do this until they're 50. But again, the analogy I would use here is comparable to that of investing for retirement. The longer you wait, the less money you're probably going to have at the end. Springs to mind this graph I saw the other day, which I'd sent to my friends, which shows that the decline, I think it was in muscle mass from when you're 30. And it makes the point that there's this line on this graph called disability. And it shows that people who didn't have enough muscle mass when they were 30, cross the line of disability when they're 70. And those that did have more muscle mass at 30 don't get close to that line.

So that for me was shocking because it goes to show that what I do now is going to determine whether I'm, by all intensive measures, disabled when I'm 70 or if I'm able. The sooner you start, the better. The drawback that young people have is, I mean, you've had a great experience because you're introspective about it and you've been able to observe it in somebody older. So you've been able to gather motivation without having to experience the decline yourself. So that's a wonderful position to be in.

For many people, that's not the case. They only begin to realize the inevitability of the decline when it besets them. But the way to think about this again is another analogy is that of a glider. So gliders eventually all have to come down, right? Our health span is basically a glider, but we have a lot of control about how long it stays in the air based on how high we can start it. So if you think about, would you rather take a glider off a really high cliff or off a low cliff, that's the decision we get to make.

And we sort of call that concept physiologic headroom. So the example you gave is a great one. So muscle mass, muscle strength provide an enormous amount of physiologic headroom, as does cardiopulmonary fitness. These are huge variables that make all the difference. And everyone's coming down, but the fitter you are, the slower the rate of decline and therefore the longer it takes before you cross below a threshold. And that threshold differs by different metrics.

But once you're below that threshold, it's very difficult to engage in activities of enjoyment. Peter, you're 51 now. 52. 52. What do you wish someone had told you when you were 32? I'm 32 years old. What do you wish someone had screamed in your face

and told you when you were my age. It wouldn't have been much about exercise. It would have been more about other aspects of life for sure because for whatever reason, I've always gravitated towards exercise. That's always been a very high priority for me. I think my advice to 32-year-old Peter would be much more about relationships and emotional health. But if I could go back and speak to 14-year-old Peter, A, he wouldn't have listened, but

I would have begged him to go a little bit easier on his body and back off on certain things that probably have led to injuries I have today that could have been prevented. Can I ask what they sent things on? Sure. I think I lifted far too heavy, far too often, and probably without enough coaching on technique. And so by the time I was 27, I had a devastating back injury. But it's one of those things that happened without any incident, which is often the case,

by the way, for a back injury. When you really blow out a disc in your back, it's not necessarily something you did in that moment. It's usually something that's been built up from the past. This injury I had at the age of 27 really was the result of years of unnecessarily heavy axial loading done with probably insufficient technique or technique that was at times sloppy and under fatigue because I used to do a lot under fatigue. I believed in training under a lot of fatigue. And I think that that's a mistake.

I think that training under very heavy load should not be done under great fatigue. Interesting. We'll talk about that as well. On that point of advice that you gave me there about emotional health, one of the things that's been very front of mind for me at the moment is men's health, specifically men's emotional health. Because I read a report that came out in March called Lost Boys, and it just details this pretty horrific picture

of men's emotional health in the UK at the moment in particular, but the trend holds around the world. And it came out in the start of March, it's been in all the newspapers in the UK, and it details a couple of sort of headline stats. The reverse gender pay gap amongst young men, so women are now earning more. You know the stats probably around soon for every-

Suicide. Yeah, suicide and one in seven young men are unemployed or out of work. All these sort of horrific stats, and then it compounds with things like suicide, suicidal ideation, et cetera, et cetera. I was thinking about this this morning when I was listening to some of your work.

I was thinking, I wonder what Peter's perspective is on what it is to be a man. Actually, it does kind of dovetail into some of your work around testosterone and the decline in testosterone. And because one of the things I was thinking about is how testosterone plays a role in what it is to be a man. But if you look at the stats around testosterone, it appears to be declining. Yes. And I say this in part as well because testosterone causes it appears to be declining. Yes. And I say this in part as well, because testosterone causes a certain set of behaviors in men that define and shape what a man is and what they want and how they show up. And even when I said earlier on protection as one of the three things I cared about,

that's probably in part because of the testosterone in me. This debate around testosterone, this conversation around testosterone and its decline, is it declining? It is. It is. Why is it declining? And does it matter? Well, I think the second question is easier to answer than the first.

I do think it matters. The why is probably multifactorial and the why is just as important as the fact that it is. In other words, the fact that it's declining is both relevant for the fact that a very, very important hormone that has incredible benefit to men and women, by the way, is going down. We have to come up with an answer to that, right? So how do we address that? Do we address it medically where we replace that hormone exogenously, meaning we give

you that hormone directly, or do we try to fix the underlying problem? So if you want to do the latter, you have to know what the underlying problem is. Now at the population level, the best answer as to why testosterone levels are declining, and unmistakably they are. So the data here are unambiguous. There's no debate on this fact. The debate is around the why. I believe that the best answer probably has to do with two things.

One is increase in body weight and fat, body fat specifically in men and some combination of reduced quality of sleep and sort of disruption to sleep. So, why are those two things relevant? So when you increase body fat, two things are happening. One is you're increasing inflammation and you are reducing the amount of testosterone that gets to stay in the form of testosterone because part of the testosterone gets converted into estrogen. So with body fat comes more of this process called aromatization or converting testosterone

into estrogen. So if you think about what those two things are doing, if you have more inflammation, that reduces your ability to make testosterone and you have more capacity to turn the less testosterone you make into estrogen, the net result of that is both of those things are reducing your total pool of testosterone. If you couple that with lower quality sleep, and I'm not talking about over the last three years, I'm comparing like now to say 40 years ago. And what are all the reasons that people might have poorer quality of sleep now?

I think there are many, but obviously phones and social media and just the stimulation of the world we live in probably plays a greater role in that. Sleep is when we make these hormones, right? So we make follicle stimulating hormone and luteinizing hormone at their maximum amount during sleep, and those are the hormones that are driving the production of testosterone. So what we've seen in many of our patients when they have low testosterone, because there's a test you can do to see if their testosterone is low because their body can't make it or because their brain isn't receiving it, or because their brain

isn't receiving enough of a signal to make it. This is a very easy thing to determine medically. Unfortunately, most people aren't subjected to that level of testing because they go to these testosterone shops on street corners that are just giving everybody testosterone. But if a physician is curious enough to understand that, you can give a patient a drug or a hormone called HCG. HCG is luteinizing hormone, which is one of the hormones made by the brain. So if you come in and you see a man who's got very low testosterone and you can't understand

why, you give him luteinizing hormone. If he still has low testosterone, you know that he has what's called primary hypogonadism, which means his testosterone is low because his testes can't make testosterone. Conversely, if you give the man luteinizing hormone and all of a sudden his testosterone goes up, he has secondary hypogonadism. You could mix the primary, secondary there, but really, the terminology doesn't mean anything. What matters is he can make testosterone, but for some reason, his brain isn't giving his body the signal to do it.

And that's a classic finding in a person who's under high stress and or not sleeping well. So that's a long-winded answer to your question, but I think that those are probably the greatest contributors to this. Now people have talked a lot about what about microplastics, what about other environmental factors, what about other factors in nutrition beyond just the ones that would contribute to excess body fat. The evidence there is less compelling, but I don't think we should discount it. But I think that if those things are playing a role, it is probably much smaller than what

we just talked about. I was thinking as you're speaking about sleep and testosterone about how, and also the link there with bad diets, how if I've not slept well, I wake up and make worse food choices. For sure. And I was like, is that like dopamine dysfunction? No, it's probably more due to insulin signaling. So we know from really good experimental studies that when you sleep-deprive people, they become insulin resistant.

And the more insulin resistant a person is, the less they're able to access their stored energy. So higher insulin resistance means greater difficulty accessing stored energy. So if you wake up and you have successive days of poor sleep and you're becoming somewhat insulin resistant, you're going to want to eat more because you're not able to access your own natural stores of fat, which is where we want to go for energy. So if you look at one experiment that was done at the University of Chicago, they took

healthy subjects, young subjects, and sleep deprived them for somewhere between 10 and 14 days. So not a huge period of time. And they only let them sleep four hours a night, which by the way, I know a lot of people who are doing that for years at a time. In that 10 to 14 day period of time, their insulin resistance was worsened by 50%. This is in other words, they do an experiment called a euglycemic clamp where they inject them with glucose to see how effectively they can put glucose into their cells, which is the hallmark of insulin sensitivity, is how well you can put glucose into your muscles

when it's infused in you. And their capacity to do that was reduced by 50% after such a short intervention. So I think sleep restriction and unhealthy sleep is a very underappreciated cause of metabolic health and weight gain. And then by extension, these other things we're talking about. It seems to me to be the thing furthest upstream in my life that then causes this cascading effect to how I show up in sort of cognitive performance, how well I can articulate myself if I go to the gym, how hard my workout is, if I choose healthy options versus unhealthy options. So it feels like that-

And mood in general. Yeah. Yeah. I mean, look, I've said this before, and I'm not the first to say this, so I'm paraphrasing others, but if you really stop to think about it, sleep doesn't make a lot of sense from an evolutionary perspective. Like if you go back in time a few hundred thousand years, why would we have spent a third of our life unconscious?

It didn't serve our purpose. You can't mate, you can't hunt, and you can't defend yourself. So you have to believe that if we could have evolved out of it, we would have done it. And we didn't. So, that means that whatever it's doing, it must be really important. I mean, core essential to our existence. While I will completely acknowledge that different people have a different necessity or requirement for how much they sleep, I still think that many people underestimate how much they need.

You know you asked me at the start, you said, what are the things that you want to do when you reach your marginal decade? And I gave you my answer. What's your answer to that now that you're a father and have a different season of life? Well, they're very similar to the types of things you're thinking about. And I love how you've got specific examples. So I really like playing with my kids, right? So I can imagine that in my marginal decade,

I'll have grandkids that are the age of my kids, right? And, you know, maybe a bit older, but as I'm even getting towards that marginal decade. Okay, so playing sports is really, really fun. I really like playing, especially because when I grew up, like I played hockey because I grew up in Canada, and then I immediately went into kind of boxing and martial arts, and those became my life. So now playing sports that I didn't play much as a kid is really fun.

Like I'm really enjoying baseball. I'm really enjoying baseball. I'm really enjoying soccer. And so when you play these things, you realize this is not an easy thing to do when you get old. To sit in the goal and actually stop a ball when a kid is blasting at you full stop, you have to be able to move around. So again, I would love to be able to play soccer, throw a football, throw and hit a

baseball as long as possible. You can get into movements that are much simpler, but if I can do all of those things, I'm in great shape. Now, of course, to be able to do that, I also need to be able to do a lot of things that many people also can't do in their marginal decade, like sit on the floor, get up off the floor under their own power, walk up X number of flights of stairs, having the strength to do that. I like doing certain things. I like archery a lot.

I want to be able to pull a bow back, obviously not at the same poundage as the current bow that I pull back, but I would still like to be able to pull a 50 pound bow back in the final decade of my life. And when you think about all those things you want to accomplish, if we were then to sort of codify them into a bunch of exercises or areas of your health that you had to now be thinking about, that I needed to be thinking about, what are the most important things? So I'm a 32 year old. What are the most important parts of my health that I should be thinking about if I want

to achieve all the things that I said to you in my final decade? No one in the final decade of their life ever said, I wish I had less strength and I wish I had less endurance. So you cannot be too strong and you cannot be too fit. The only time that one would throttle back on the pursuit of those is A, if doing so is coming at the expense of something else, either with respect to your health or your life, and two, if the pursuit of that at such an extreme level produces risk of injury. Okay.

So in other words, could I be stronger than I am today? Yes. I'll give you an example. We know that in resistance training, the sweet spot for pure strength is one to five reps. When your goal is to maximize strength, you need to be pushing one, two, three, four, five reps. Once you start thinking about hypertrophy, two, three, four, five reps. Once you start thinking about hypertrophy, muscle size, we're starting to think about seven, eight, nine, 10, 11, 12 reps.

Once we start thinking about muscular endurance, we start thinking about north of 15. Those are the general patterns of resistance training. So if I want to build my muscles because I'm going for aesthetic goals, then I need to be aiming above five reps. I need to be 10 or 12. If I'm just purely thinking about strength, bigger weights, but lower reps. That's exactly right. Okay. And then if I want muscular endurance, which is even higher reps.

Okay. Lower weight. Yep. Okay. So again, we could go into much more detail around that, but just to finish the point here, why do I not do much training at one to five reps? In fact, these days, I don't do any training at 1 to 5 reps anymore. Why? Because to train at 1 to 5 reps comes at a risk, especially for heavy compound movements. So I'm OK getting a little bit less of a strength benefit, while still, of course, getting stronger, but training at a higher rep load.

So I'm typically, so I'm targeting eight to 12 reps with one to two reps in reserve, is basically how I'm doing my resistance training. That means every set I'm doing, I would expect to get to within about one rep of failure somewhere. So today when I lifted, I don't think I did less than seven. I didn't do more than 12.

And the weight was always titrated so that I was either failing, almost failing, or one rep away from failing somewhere in there. And I was adjusting the weight constantly on every exercise to get there, with the exception of one exercise. I did push-ups was one of the things I did. Push-ups are kind of more in the muscle endurance. Obviously, I'm doing more reps when I was doing push-ups. But pretty much everything else was in that range.

So again, I'm not fully maximizing strength anymore because the cost of it might be a little bit high in terms of injury risk. Similarly, I'm not strength training 24-7 because I need to make time to do my endurance training and other types of training. How often do you train resistance training? I resistance train three times a week. And how often do you train generally? I train every day.

Every day? Yeah. Why? Because, you know, again, the intensity of my training is not that high, at least three days a week. So the three resistance days are pretty hard because I'm really only doing each body part once a week. So when I'm doing it, I'll spend that 90 minutes really hammering those body parts. Three of those days are just zone two. So three of my four cardio days are zone two days where I'm doing, you know, I'm on a bike

and I am riding at a level of intensity that actually allows me to still talk. You know, not talk like I am now, but talking in sort of a strained way. So for me, that's about a heart rate of 140 beats per minute. And that's just not taking a huge toll on me. Those are almost like recovery days for me. And then one day a week, I do a really, really hard VO2 max day. And that's a really hard day. That burns a lot of matches.

That's tomorrow. Not looking's a really hard day. That burns a lot of matches. That's tomorrow. Not looking forward to it already. Do you do cardio on your resistance training days as well? No, I don't. So it's the seven, it's four days of cardio, three days of resistance. Now that's going to change in the summer when I'm going to add three days of swimming

and I will end up doing some swims on some resistance days. So before you do your resistance workout, you don't go on the stepper for 20 minutes or cycle for 20 minutes or something? I don't. Is there a particular reason why? It wouldn't really serve a purpose. So I know a lot of people do that. I know a lot of people will say, hey, I'm going to do a little bit of a warm up on this

treadmill or the step master before I lift. But I actually have a pretty strong point of view on how we should warm up to lift. And I don't think walking on the treadmill or running on the treadmill or being on the StairMaster on the bike is a great prep for the lift. I think it's better to warm up for a lift doing movements that prepare you to lift. So for example, like if it's a leg day, so Monday's leg day, right? So what am I going to do? I'm going to start by doing a bunch of core stabilizing stuff.

So I'm going to do a whole bunch of this dynamic neuromuscular stabilization stuff. So you get into basically these baby positions and you really learn to activate your core as you move around in a six month position and stuff like that. I then do a whole bunch of like like you know what a 90-90 is or a shin box exercise is, where you're kind of on the ground in a position where you're really, you know, you can start out doing it isometrically, but ultimately going through a slow, eccentric,

and concentric phase of movement that's kind of activating glutes. So I go through basically a whole DNS sequence. Then I get into a dynamic movement prep. So then I get into a bunch of bouncing, a bunch of footwork, and then I start with really light weights. So I'll go to a leg extension machine and do very, very light leg extensions,

very, very light leg curls, come back and do more jumping and moving and lunging and go back and forth. So I'll spend 20 minutes doing a warm-up, but the warm-up is geared for me to lift. Whereas if I had just sat on a bike and pedaled around, that doesn't actually replicate any of the movements I'm going to do when I start loading myself. I've got particularly concerned about injury now that I'm 32,

because when I was 30, 20, I could do almost anything it seemed, and nothing would break. But I had a couple of injuries when doing like shoulder presses and things like that. And one of my friends had a similar injury recently, which took him out for three or four months, where he did a shoulder press, pulled something in his back or something, it was like a neck.

And then he couldn't turn his head anymore. In terms of injury, if I wanted to get injured, am I right in thinking that the thing that leads to injury is basically just walking straight in and trying to lift something heavy? Or is there things further upstream that cause injury in the gym? No, that's one way to increase your risk of injury for sure. But yes, there are other ways that it can happen. And I think about it a lot.

One of the injuries I think a lot about are Calf injuries Achilles injuries sort of tendon injuries. This is I think one of the things that Becomes a real problem for people as they age, you know, you you often hear about people my age Tearing and Achilles. Yeah, it's a devastating injury now again It's not devastating and that you won't recover from it, but boy, it's going to take you out of commission for six months. So a lot of these injuries happen because the individual still has strength, but they've kind of lost some of the pliability in the tendon because they've kind of lost some of the jumping. That's why I always start these workouts with low level of jumping.

And I'll progress to higher levels of jumping. But jumping is actually a very important part of training. And it's one of the things that we take for granted. But boy, when your ability to jump is gone. And jumping, by the way, can mean like just initiating a jump. But it can also mean jumping off something and stopping yourself. Those are really important skills. And so something like jumping rope is really important, right?

Your feet are just kind of moving like that. They're acting as shock absorbers. Calfs and Achilles have to constantly change in length. And that accommodation is a really important part of resilience. And I think that should be an important part of everybody's warm up at a minimum, if not part of their workout. One thing I'd love you to do is to persuade people listening that muscle mass matters for longevity.

And also, if you can within that, that leg day matters. Because we all avoid leg day, including me. And sometimes I need to be told again why it matters for me to add it. Well, I mean, I think, look, muscle mass is probably the second most highly correlated finding or third most to longevity after strength and cardiorespiratory fitness, VO2 max. So why is that? So first of all, I think that muscle mass is both directly a proxy for strength. In general, the more muscle you have, the stronger you are.

We all know exceptions to that. We know wiry little people who are insanely strong. And I have patients like that. They're just naturally thin people. But when we put them through the testing protocols, they're remarkable in terms of their strength. And I tend to not worry about the fact that they're slight and build when I see that they're strong across the board. There is another benefit of muscle mass, which is it's the place where you dispose of glucose.

So from a metabolic perspective, the more muscle mass you have, the more glucose buffering capacity you have. And why does that matter as I age? Because one of the hallmarks of aging is a reduction in the capacity to metabolize and buffer glucose. And so as glucose levels become less and less regulated, all sorts of bad things happen. Bad things happen to micro vessels in the body. So if you think of the most extreme example of this is type 2 diabetes.

So once a person has type 2 diabetes, what are they at risk for? They're at the risk of reduced vision and ultimately blindness, amputations of their digits, impotence, right? The penis has tons of tiny blood vessels in it, and the more that glycosylated proteins accumulate there, the less they get blood flow, and obviously damage to the small blood vessels of the brain as well.

So all of these things are hugely problematic when glucose is dysregulated, and again, the most important thing that you can do to regulate glucose, in addition to the obvious, which is eating an energy balance, not eating too much, is making sure you have large insulin sensitive muscles, which means large muscles in the context of an individual who's sleeping well and exercising. And you're going to basically have a great place to put all of that glucose when you consume it.

And is that going to stave off me getting belly fat? Because my glucose're going to basically have a great place to put all of that glucose when you consume it. And is that going to stave off me getting belly fat? Because my glucose is going to be stored in the muscles as opposed to somewhere else or? Again, it all depends on the total energy balance, but yes, it's clearly going to make a difference, right? So one of the surest ways to reduce your capacity to store fat is to add more muscle. Okay. I did the grip strength test. I've done it twice now. Meaning you did one of the grip meters or you did a hanging test? One of the grip meters. I actually did it at Brian Johnson's house, but I also did it with Andy Galpin. And people tell me it's an indicator of longevity,

but I've never really understood why. Is it just testing my strength? Yeah. Grip strength, of all the strength metrics, it's one of the most highly correlated with longevity. We actually prefer to do it like a 10 squared, where your colleagues tested yesterday. We prefer to do it on a dead hang. So we make them hang from a bar. And we just time how long they can hang. So that's a really good metric of your grip strength

because it's also normalized to your weight. Okay. So we wanna see that people can hang for at least two minutes on a bar. And so the question is, why is that so highly correlated with longevity? And it's what you said, it's strength. And the reason for it is it's really hard

to be strong anywhere in the upper body if your grip is weak. Like if you think about being able to push, especially being able to pull, like all of the real metrics of upper body strength require a strong grip. And if you have a strong grip, you have a strong hand, you have a strong forearm, you have a strong scapula that is connected to your rib cage. It goes up the whole chain. That's another reason why we like the dead hang as a way to test it, because the dead

hang is testing everything. It's testing your actual grip. It's testing your scapular stabilization, the stability of your shoulder. It's basically testing that entire chain. Then I also think there's a practical side of this, right? It's very underappreciated what frailty does to an aging individual and what sarcopenia, loss of muscle mass, does to an aging person and what it is about falling that is so devastating to an older person. And the stronger your grip, the easier you're able to navigate a lot of those things, right?

It just seems unthinkable that falling is something I should be thinking about at 32 in the future. Like, because my mobility... It seems ridiculous. It seems ridiculous, yeah. Yeah, and yet it is devastating. So once you reach the age of 65, which that ain't that far. I mean, if you know 65 year olds all day long, that's not a very old person. far. I mean, you know 65-year-olds all day long.

That's not a very old person. Once you reach the age of 65, your mortality from a fall that results in a broken hip or femur is 15% to 30%. Just think it is such a staggering number. So you're over 65, you fall, and that fall results in the break of a femur or hip. There's a 15% to 30% chance you'll be dead within a year. What kills me? It could be something very acute like you bang, the fall that's significant enough to

do that also bangs your head. It could be that you get a fat embolism, you get a blood clot. It could be that during the recovery process of this, you just never really get better, you never thrive again. I think a more disturbing statistic is that of all the people who survive, 50% will never again regain the level of function they had before the injury. So they will require a cane for the rest of their life or something like that. Now, there are lots of things that account for that.

Andy Galpin, who you mentioned a moment ago, talks a lot about this, but a lot of it comes down to foot explosiveness, power. So the reason you're not really afraid of falling, like when was the last time you were walking and your foot caught something and you slipped? Like yesterday? Yeah, quite often. Yeah, exactly. Why don't you fall when that happens?

Because I can quickly readjust. Right. That's power. So you have the power in your foot to readjust when you lose your step. You step off a curb not realizing it. It doesn't matter. You readjust.

OK, those are a very, very specific muscle fiber that is responsible for that. It's called the type 2B muscle fiber. That is the first fiber that atrophies when you age. In fact, you're already at your peak. It's all downhill from where you are now. Thank you so much. Yes.

I'm already 20 years past you, and my power is a fraction of what it was 20 years ago. Now, I fight like hell based on the exercises I do to try to make, to try to keep it as high as possible. So the reason that these people who were in their 70s are falling all the time is people think it's a balance thing. It's not just a balance thing, right? It's that they're undergoing the same insult you and I undergo on a daily basis, but the difference is their probability of being able to catch it, either through the explosiveness

of their foot or their lower leg, coupled with maybe not being able to catch it, either through the explosiveness of their foot or their lower leg, coupled with maybe not being able to grab on to something as quickly and adjust, it's a power deficit problem. So what do I have to train now at 32 to ensure that, specifically the example of hitting something and quickly being able to adjust, I'm able to do that when I'm 70. I think jumping is a great way to do this, right? So I mean, I use certain specialized pieces of equipment that actually have power built into it because power is different from strength, right?

So strength is really the ability to move, is just the ability to move a force independent of the speed at which you move it. Power is the maximum combination of force and speed. Okay. So, if you, on the x-axis, if you were to put force, and on the y-axis, if you were to put power, the curve is an inverted U. So, as the force or the weight that you're moving goes up, and you're trying to move it as fast as you can, you're getting more and more and more and more power. But then at some point, the weight gets so heavy that even as you continue to move it, it's going slower, you're getting more and more and more and more power, but then at some point the weight gets so heavy that even as you continue to move it,

it's going slower and slower and slower, so your power is going down. So there's a sweet spot there. So one of the things I do is there are certain specialized pieces of equipment that allow you to train in that way. So I definitely rely on a lot of those, but even if you don't have access to that machine, jumping is a really important way to generate power.

So if you're just doing a vertical jump, that's power. What about balance? I was at Brian Johnson's house, and as he was cooking his breakfast or lunch or whatever, he was balancing on a half ball. You've seen one of those things. Yeah, yeah. I don't think I asked him why he was balancing on it, but I assume it was to do with balance and there's certain muscles in the leg?

There are lots of exercises that are great for balance. Anything that produces instability is great because it's, for lack of a better term, I've heard it described as problem solving for your foot. Okay. Right? So if you think about being on any unstable surface, even if you're just walking on an unstable surface, so if you were to look at a person's foot, their lower leg actually, as they're walking on a surface that's constantly changing, so like a gravel path or something like that,

you're going to see, like if this were my lower leg, you would see the musculature of the lower leg constantly adjusting to it. And so yeah, I really enjoy things that force that type of training. Do you do flexibility stuff? Yeah, so I'm actually naturally a pretty lax person. So I don't do any stretching, if that's what you're asking, but all of the sort of stability and dynamic stuff I do incorporates movement at end ranges. So I'll give you an example of why I think the notion of flexibility might be a little bit misunderstood.

If you ask a person to stand up and with their legs straight touch their toes, most people would say that's a great test of flexibility in the hamstring. And most people can't do that. What they don't realize is everybody's hamstrings are long enough to allow them to do that. The reason they can't do it is their central nervous system will not release them to do it. Does that make sense? Interesting. The central nervous system won't release them to do it. Does that make sense? Interesting. The central nervous system won't release them to do it. That's right.

It doesn't feel safe for them to do it. How do I know this? Because if you take a person under general anesthesia, you can put them into almost any position possible. So if you took a person under general anesthesia, laid them on the operating room table, you could lift their leg up to here. When they're awake, you couldn't get it past here. When they wake up from surgery, will they have a torn hamstring?

Not at all. They won't even know their leg was moved. The difference is when they're under general anesthesia, their brain is not sending a signal to the leg that says don't lift. So why is the brain doing that to the individual? This is how I learned it on a personal level. So about six years ago, I had tweaked my back and had just done a unnecessarily heavy set of deadlifts and just pushed it a little too far.

And I was kind of nursing this sort of just very, very tight QL. I was completely jammed up. I came in to do some training with a friend of mine who's one of the guys that—actually, he is really the guy that introduced me to this thing called DNS, dynamic neuromuscular stabilization. I mean, I was stiff as a board. I couldn't get past my knees bending forward. I'd been hurting for like three days.

And we went through a series of exercises for 40 minutes, which included me laying on my back with my legs up, him leaning on top of me, so my feet are here on his chest, and doing isometric pushes while working on generating intra-abdominal pressure. And after maybe 40 minutes of this type of exercises, I was palms on the floor. Now, how do I go from not being able to get to my knees to palms on the floor in 40 minutes with three days of horrible back pain. The difference is when my back was hurting, my body was not going to let me go down. The body was saying, no way, your back, I'm protecting you because you are not stable.

You're not going to go any further. What we went through with this exercise and a series of exercises was basically, I mean, I'm oversimplifying this and sort of anthropomorphizing it, but letting my brain know it's okay. You're stable. You're stable. You're stable. The back is safe. The back is safe. Let him go.

Then, ah, palms on the floor. I love testing this. Sometimes I'll just wake up in the morning and do five minutes of breathing exercises when I'm stiff as a board and just get into a position on the floor. Why the breathing exercises? Because that's really how it's the breathing is

how I kind of create this cylinder in my abdomen to sort of push the floor of the cylinder down as the pelvic wall, the diaphragm is the cylinder, the top, and then the entirety of my abdomen is the wall of the cylinder. And so I kind of go through these exercises every single day, usually on my back actually, that's kind of like part of my warmup. And it's just a way to kind of ground myself around creating concentric pressure in the abdomen.

Just to get some tips from you around your strength training regime. How many exercises do you do? What does, I'm really curious, so you train three days a week doing strength and resistance stuff. Do you do like shoulders and back and as like a, you know people use to clap their hands and stuff. Yeah, yeah, exactly. So on Monday is pure lower body.

Okay. And Wednesday is pure lower body. And Wednesday is arms and shoulders. And Friday is chest and back. Super simple. Nothing, no rocket science. An hour? I mean, it's like an hour and a half of lifting, plus maybe 20 minutes of the warm up stuff.

So on the chest and back day, how many chest exercises are you doing? Four. Four, okay. And then four on back. Yeah. Okay. And I'm just super setting them. And I'm going to do maybe five sets of each, so five working sets.

So there's a lot of warm up in there too. And I'll also do some other stuff like some med ball slams or things like that as well. It's been this huge rise in people doing these hyroxes and sort of elite endurance events and such. It's really interesting that it's become so popular. Even things like running clubs I know, but the fact that people, more people are doing marathons now than ever before. Why do you think this is happening? I don't know. I mean, I think it's a very net positive thing, though. I mean, I do think that there's more and more people that are taking up things like

rucking and running and finding camaraderie in these things. The only thing I hope is that people are doing it in a manner that's sustainable and safe and allows them to do it indefinitely. So I'm always hopeful that whatever thing that people are doing, they're not injuring themselves. Because again, rule number one is don't get injured. So you're playing, the name of the game is to play the game as long as possible. In front of me, I have a bunch of different graphs

and images and some of them relate to a word you said earlier on, which is VO2 max. And this is something I've heard you talk about previously, but for anyone that doesn't understand what VO2 max is or why it's important, can you explain what it is and why it's so critical to longevity and health span? I think most people will be familiar with the idea that we are obligate anaerobes, which in English means we cannot survive without oxygen. Okay.

So why is that? So oxygen is absolutely essential to catalyze the chemical reaction that turns food into a currency for energy called ATP. So everybody's probably heard of ATP. ATP is the money, the currency of energy in our body. Anything that interrupts the production of ATP is fatal. An extreme example of that is cyanide. Everyone's heard of cyanide as a poison.

If you take cyanide, you'll be dead within seconds because cyanide blocks one of the transporters in the production of ATP. So, it just gives you a sense of how critical it is to have an infinite and abundant supply of ATP. Oxygen is also essential for that. That's why without oxygen, you can only survive for a couple of minutes. Longer than you can without cyanide, but not much longer. So how does it work?

So we breathe in air, and that air goes into our lungs, and that air goes through our lungs into these distal things called capillaries, where hemoglobin is bringing the waste product called carbon dioxide back to the lungs. And there's a gradient of partial pressure between oxygen and carbon dioxide such that a switch takes place. The air that we breathe in delivers some of its oxygen to the hemoglobin molecules. And the carbon dioxide diffuses off that into the air. And we breathe out air that is lower in oxygen and higher in carbon dioxide

than what we breathed in. So if I go, that was high oxygen, low carbon dioxide. That was low oxygen, high carbon dioxide. And that's happening every second of every day. That oxygen, that hemoglobin molecule that's carrying oxygen is carrying it to every cell in my body because every cell in my body needs oxygen. And that cell in the body is taking the oxygen to run that chemical reaction to make ATP and it's shuttling back carbon dioxide.

And it's just the most incredible thing in the world to imagine how frequently this is happening. And the more you exercise, the more you consume oxygen. So oxygen consumption is a proxy for energy demand. So we can measure this. Now to do so, you have to put a mask on because I have to be able to measure very precisely two things. I have to be able to measure exactly the flow rate of air going in and out of your mouth, and I have to be able to measure very precisely the concentration of oxygen coming out.

If I know those two things, I can calculate how many liters per minute of oxygen you are consuming. So you and I sitting here right now are probably consuming less than half a liter a minute. Call it 500 CC a minute of oxygen right now. Because you have to consume some to be alive. And look, I'm moving my arms around, and you're nodding and taking notes. So if you're sleeping, you might be consuming 300 milliliters of oxygen per minute.

That's the lowest level. If you were to get up and we were to walk around here, that number might go up to 800 milliliters per minute. If we were to walk a little more briskly, we might be at a liter per minute of oxygen. If I said, let's go out in the parking lot and jog, well, we might get up to like 1.5 liters per minute. Pick up the pace a little bit, we'll get to 2 liters per minute. If I start really, really running us hard, we're going to get to three and a half, four liters per minute. Well, at some point, I am going to push you so hard that

you will achieve your maximum level of oxygen consumption. And if I push you any harder and faster, you won't extract more oxygen from the air. You may go faster, but you will do so through a process that does not involve the consumption of oxygen. You will do so through an anaerobic glycolytic pathway, but you will have achieved your maximum consumption of oxygen. And that number has a very special name. It's called VO2 max.

So VO2 max measured in liters per minute is the maximum amount of oxygen you can consume. And the only way you can measure that, again, is to have this mask with very, very fancy apparatus that measures both of those things I said, and you have to be stressed hard. So, we typically do this on a treadmill or on a bike. So your colleagues that came into 10 Squared yesterday, they did it on treadmills. They ran and they ran them and ran them and they ran them until they couldn't go any faster. And then we measured how many liters per minute

of oxygen they were consuming. Now that answers what VO2 max is. So the next question is, does this matter? Well, the short answer is, we don't have a single metric of humans that we can measure that better predicts how long they will live than how high their VO2 max is. And it's not even close, to be completely clear. So if you compare somebody who is in the top 2% to someone who is in the bottom 25% for their age, the difference in mortality is 5x.

500%. Yes, 400% technically, because with hazard ratios, you go 2x hazard ratio is 100%. I guess. Yeah. So let's look at you. So I see you've pulled this chart out, which is one of my favorite charts. OK.

So you, oh, by the way, there's one other thing I should state. We normalize this by weight. OK. So we always divide that number of liters per minute by how many kilograms you are. So the number is actually reported as milliliters per kilogram per minute. Okay.

Okay. All right, so if we look at somebody who is your age, male, 30 to 39, if their VO2 max is below 35 milliliters per kilogram per minute, they are in the bottom 25%. kilogram per minute, they are in the bottom 25%. Conversely, if they are at 53 milliliters per kilogram per minute, they are in the top 2.5%. So to be clear, if you take a 35-year-old man and one of them has a VO2 max of 53,

and the other one has a VO2 max of 35, there is a 400% difference in their all-cause mortality over the coming year. Wow, okay, so all-cause mortality, anything killing them over the coming year. That's right. Now this becomes more and more profound as you age, because the all-cause mortality ratio

for a 35-year-old is incredibly low. It's like 1%. So, that means you're comparing 1% to 4%. It's not that big a deal. But when you get up to my age, so I'm two decades older than you. So now, the low bar, the bottom quartile is less than 29. The high bar is more than 50. Well, my relative mortality in the next decade is probably 2% to 3%.

So now multiply that by 4. When I get into my marginal decade, the low bar is 18. The high bar is 18. The high bar is 36. That's a 2x difference in VO2 max. A 4x difference in mortality is huge when the all-cause mortality for an 85-year-old is going to be the one-year mortality for that person is more than 10%. One of the things that we do is we think through this, not just through the lens of mortality, which is what I just walked you through here, but also health span, which is what you were

talking about earlier with the graph of strength and disability. So we have another figure that we show people that on the x-axis shows age, and on the y-axis shows VO2. And it has a whole bunch of lines that come across that show various activities. If you want to be able to run a six-minute mile, you have to have a VO2 that's very high. If you want to be able to run an eight-minute mile, a 10-minute mile, if you want to be able to run a six-minute mile You have to the vo2 that's very high if you want to be able to run an eight-minute mile a ten-minute mile If you want to be able to climb a flight of stairs without getting out of breath Like it shows all of these different things and you see what the required vo2 is Mm-hmm. I think in fact we might even have these graphs in here

Yeah right there so Yeah, right there. So we put your dot on the graph and we say, if you stay where you are, meaning right at that green curve, you're in for a great life. Why? Because even when you're in your 80s, you're still going to be able to do all of those things. So the results you're looking at here are Jack's results, who runs the production here. He came to your center, came to 10 Squared and Austin, he did the test, I think he was on the treadmill

for like an hour or something like that. And can you explain to me exactly what his results say as it relates to what you were just describing? Yeah, so he did both a Zone 2 and a VO2 max test. So Jack got on the treadmill and there's a protocol for how you warm somebody up. You really want them to be able to get to a maximum effort. You don't just put them on a treadmill and crank it up. You take your time getting them up there.

And he had an amazing result. So his VO2 max was 4.1 liters per minute. And he achieved that at a heart rate of 204 beats per minute, which is higher than what was predicted for his age. If you normalize it by his weight, he was at 56.5 milliliters per kilogram per minute. So when you look at his age, because he's in his 20s, he was at about the 97th percentile for his age, meaning his VO2 max was higher than 97% of people his age. And so, out of the gate, that just tells us from a longevity standpoint, our goal is to

keep him there as long as possible. I mean, we're so ambitious with our patients and clients that we actually want them to be, as an aspiration, to be two decades younger at the top 2%. So if you're 50, you want to be VO2 max north of 53. And then the other thing we do is we check on something called heart rate recovery. So in 60 seconds post VO2 max, how long does it take?

How many beats does their heart rate come down in one minute? This is also a very powerful predictor of mortality because it's a huge indication of what's called parasympathetic balance. So it's basically a question of how much is their autonomic nervous system in favor of sort of a stress response versus a recovery response. And so the gold standard here, we want to see people that can recover at least 30 beats in the first minute. He did pretty well.

He recovered 28 beats. If you're really, really fit, you're going to be 40, 50 beats of recovery within the first one minute. It's incredible. Then we tested his lactate levels, and we ran him for what we called zone two testing. Zone two is his aerobic base. This is where he should be spending 80% of his cardio training time should be in this energy system.

So it's hard enough that it's not just pure recovery, but not so hard that it's pushing energy systems that are higher. This is a pace he should be able to hold for an hour, and he should certainly feel like he's working but not feel it too much. Technically it's also a place where he's got maximum fat oxidation. So we do this also in the same measure on a treadmill. This is a bit more of a complicated test because you're titrating between how he feels and what his blood lactate levels are.

Maybe not to get too complicated in the weeds on that, but we're simultaneously looking at the ratio of how much carbon dioxide he produces to how much oxygen he consumes. That tells us how much fat he is using in his own body. We look at that number, and he maxed out at 0.77 grams per minute, which is very good. One gram per minute of fat oxidation is exceptional. So 0.7677 is pretty darn good. His lactate hit about two millimole, and he achieved this running at 7.3 miles per hour. So again, there's a lot to unpack in there, but that gives us a pretty good sense of his

level of fitness. And for a guy in his 20s, that's really good fitness. He does a lot of running. Yes, yeah. Yeah, yeah. But even this test is a bodywork. We normally would separate these two tests on two separate days. So people who come to 10 Squared are not from Austin, they're from all over the place.

So they come in for two days of testing, and you got to sort of figure out a way to take a person who's not necessarily that fit and allow them to do these tests. So it's kind of broken up over to a couple of days so they can mix it with the strength testing and all the other stuff. And if you were advising Jack on how to improve some of these scores here, what would you say? So the truth of the matter is looking at his stuff here, I would say, I think you've got the endurance thing really covered. In his case, there were other issues that were uncovered during his intake that were of more concern. This is a matter of now what we think of as portfolio management.

When your VO2 max is in the top 2%, when you're fat oxidizing 0.7, almost 0.8 grams per minute, and he's got a heart rate of 165 to 170 when he's in zone two. I mean, this guy's cardio is dialed in. Just for a second, I want to talk about a company I've invested in and who sponsored this podcast called Zoe. Like me, many of you are big on tracking your fitness and your sleep, but how many of you understand how your body handles food? Metabolic fitness is all about understanding your metabolism's response to food, and we

all react differently. So Zoe created a test to see if you can how your body handles food. Metabolic fitness is all about understanding your metabolism's response to food and we all react differently. So Zoe created a test to help you understand how your body responds and it starts with their famous test cookies which are identical test meals with the same sugar, fat and calorie content of the average meal and therefore acts as a metabolic challenge. You also wear a continuous glucose monitor that tests your blood sugar levels. I've done this test and it left me wondering how my metabolic fitness compared to others like me

and my results revealed everything. So if you'd like to learn about your body's response to food, head over to zoe.com to order your test kit now. And if you want a discount, use code Bartlett10 at checkout for 10% off your membership. As a Zoey member, you'll get an at-home test kit and personalized nutrition program And if you want a discount, use code Bartlett10 at checkout for 10% off your membership. As a Zoe member, you'll get an at-home test kit and personalised nutrition programme to help you make smarter food choices that support your health.

That's zoe.com with code Bartlett10. I've got a story that I think you'll be interested in hearing and it's brought to you by my show sponsor Fiverr. About six months ago, my team and I sat down to try and work out how we were going to build the most valuable newsletter for ambitious entrepreneurs ever. And after hours of discussion, we finally agreed that to tip the odds in our favour, we needed to be constantly experimenting. But to do this, we needed manpower or womanpower. So we hired a group of freelancers through Fiverr and tasked them with testing different elements, which are like the visuals in the newsletter, the subject lines, the copy links and even after launching 100 CEOs,

the new newsletter and getting 93,000 signups on the first day, our experimenting hasn't stopped. I'm confident we wouldn't have seen the same success had we not experimented in this way and our freelance support from Fiverr was critical to that. So next time you're launching something, find your failures and fix them fast with Fiverr freelancers. Visit fiverr.com slash diary today and use code DOAC for 10% off your first order. These are Jack's results. So I've invited Jack in because I

feel like he might have some questions and you might have some questions. So you guys go ahead. All right. Well, first off, Jack, thanks for being an awesome guinea pig yesterday. You hit it out of the park as far as your cardio training. So tell me a little bit, what are you doing for cardio?

How often are you running? So I actually stripped it back quite a lot. I've probably started maybe like two years ago going really heavy on running, and that's all I did. And then I started getting a little bit injured. So now I've cut it back, but I'd say I do like one long run a week, and that's like 20K. Outside of that, I don't really do much other cardio.

Interesting. I know that the team talked to you about your left foot. Yes. And did they show you the pictures on the treadmill? They did, yeah. Super interesting. Super interesting. I sprained my ankle really badly like six months ago. Yep. So they said that could have been something I think it's very likely that the ankle sprain has not has changed your gait such that you

Probably are going to develop an injury over time with your running if the if your pattern is not corrected so you're overcompensating on the left and Did I assume that I assume you noticed the difference in the height of your shoulders and your head and everything while you were running. So even though the engine is working insanely well, this test only measures the performance of your engine. Your chassis, which is a subjective assessment, to use the car analogy, shows that the chassis is a bit weak.

OK. I'll give a bit of context on what that actually was. So when I was running on the treadmill, I think it was Kyler, he showed me a picture afterwards of me running and basically my head was right in the middle when I went on my right side. But then when I went on my left, my whole body was a bit lopsided. So yeah, that's kind of what you're talking about there.

That's right. And again, the good news about running is each step is very light. But if you're running 20k, that's a lot of steps. So even something that's a light impact but done thousands of times will produce a problem. OK. So let's shift from how well the engine is, which is exceptional. At both ends, by the way, to be clear, your peak engine output, which is VO2 max, was awesome.

And your engine efficiency, which was your zone two, your fat oxidation, exceptional. We do have this issue in the chassis that needs to be addressed or you're going to get a repetitive strain injury. So then the next thing that the team did was just a very simple test called the DEXA scan. But we do a more comprehensive one. So we're looking at all the bone density, left hip, right hip, lumbar spine, and then total body fat, total muscle mass, and then visceral fat, which is fat around the organs. I think the most surprising aspect of the test was your bone density.

So a DEXA scan measures bone density very accurately and both sort of across the board in terms of your lumbar spine and your right hip and your left hip, you were in your lumbar spine two standard deviations below the mean for someone your age. So that means basically you're in the bottom 10 percentile of bone density for a guy your age. And for your hips, you're not much better. Both in the left and right hip, you're about 1 and 1 half to 1.7 standard deviations below the mean. So what does that mean?

That means that you already have something called osteoporosis. So when your T score, which in your case is almost the same as your Z score because of your age, but the Z score compares you to someone your age, the T score compares you to someone 30 years old. So when your T score is minus one, you have osteopenia. And when it gets below minus 2.5, you have osteoporosis. Those are just technical definitions of bone density. The problem is your risk of bone fracture goes up really significantly.

Now because of how young you are, it's not like I'm worried you're going to walk out of here and something's going to go wrong. But the risk of you sustaining an injury in sport is not trivial, right? So if you were out skiing and Stephen was out skiing assuming he had normal bone density and you guys both took a tumble, I would be, assuming he had normal bone density, and you guys both took a tumble, I would be infinitely more worried about your bone density. We have patients in our practice who do. They're young, healthy people, and they get these freakish fractures while skiing or playing

sports and things like that, and they have really low bone density. It's just something we want to address. The bigger concern is that what is the story of this going to be when you're 60 and 65 and 70? And that's the one where we really want to mitigate it. So I know that the team talked to you about making sure you follow up with an endocrinologist. You want to make sure that there's nothing here that is medically obvious to be treated, such as vitamin D deficiency, anything that has to do with parathyroid hormone or calcium,

and things that are medically obvious to treat. The most important behavioral thing that a person can do with low bone density beyond correcting all the nutritional deficiencies that can lead to it is applying heavy load to the bone. So bones are active pieces of tissue, even though we don't think of them that way, and they respond to deformation. So, you have to put strain into a bone for it to respond and strengthen. And it's counterintuitive that running is not amazing at doing that.

It's not bad. So, in general, runners have better bone density than sedentary people, but not by much, believe it or not. Swimmers and cyclists, believe it or not, actually have lower bone density on average. But resistance training with heavy weights is actually kind of what is necessary. Grappling as well, by the way. So people who do jiu-jitsu, strength training, resistance training, those are the ways that you're going to increase this. So I would say that was the first finding that is important and worth discussing.

Do you have any questions on that? Because I've got a couple. Well, I think my first one was, so I only actually started lifting weights properly maybe two years ago. So that's probably why you're seeing that. Maybe. I mean, I guess, did you have asthma as a child or anything? No.

I know when I, my mom said something about when I was born, I had low calcium, something about low calcium, they had to put something on my teeth, but I don't know what that is exactly. Well, if you had low…if there's something that was impacting your calcium levels when you were little, that would certainly be a potential risk for it. Our bones are mostly formed for males in the early 20s, for girls typically in the late teens. So anything that disrupted calcium metabolism when you were young could have played a role

in this for sure. The reason I asked if you had asthma is a lot of the times we see folks that had any medical condition that required corticosteroids, prolonged use of corticosteroids would be another big risk factor. Of course, there's also genetics, so probably worth knowing if your parents themselves have low bone density. But it sounds like there's something going on with calcium metabolism as a kid that might have played a role.

The reason it is really important to connect with an endocrinologist now is there are actual medical treatments that can increase bone density in addition to all of sort of the total optimization of the nutritional stuff, vitamin D, calcium levels, things of that nature, and of course the training. Are there specific exercises I would do to increase that? Or is it just an all-around kind of training? No, I mean, I think if you think about the long bones of the body, which are the ones that we're basically measuring here, I mean, the short bones in the spine, but the femurs in hips, anything that puts

those things under deformation. So, anything from a farmer's carry to a step up to a box squat, I mean, it's whatever you can do safely that's loading you and placing these bones in a manner that forces them to actually undergo deformation. And the other thing I would also make sure of is that someone's checking your blood levels to look at things like testosterone and estrogen. So estrogen, believe it or not,

probably the most important hormone besides vitamin D in bone health. So you can think of a bone as something with a strain gauge in it, and as the bone is deformed, the strain gauge sends a signal, a chemical signal to cells that build the bone. The chemical signal is estrogen.

So the reason women are so susceptible to osteopenia and osteoporosis is once they go through menopause, many of them lose their estrogen if they're not placed on, well, they all lose their estrogen, but if they're not placed on hormone replacement therapy, they don't get it back. And so they lose that chemical signal. So women see a rapid drop off in bone density at menopause. Peter, is this graph accurate, roughly? Yes, this would be accurate.

So if this is broadly accurate, what is the game then for someone like Jack? Is it building bone or is it preventing looks? Preventing decline, yeah. Okay. Preventing decline. Most of us reach our peak bone mass in our 20s. Okay. Yeah. So the name of the game is prevent it from getting any weaker.

The good news is, by the way, I had a woman on my podcast named Belinda Beck who studies osteoporosis. She's from Australia and she did this amazing study there called the Liftmore study where she enrolled a bunch of women with osteoporosis who had never done any resistance training and half of them were randomized to the usual activities like yoga and things of that nature. Then half of them were randomized to heavy resistance training. The women that did the heavy resistance training actually, first of all, on DEXA saw no change in bone density or saw a very minor reduction in bone density compared to a significant

reduction in the women who were not resistance training. But more importantly, on CT scans, the women who had done the resistance training actually showed an increase in cortical thickening of bone, suggesting that it might even be that DEXA is not by itself sufficient to fully assess bone health. It assesses bone density, but not necessarily bone health. And her hypothesis is that these women might actually be getting stronger bones, even if the density is going down just a little. But either way, even if density were sufficient, the fact that their density went down so much

less than the others Was amazing and it's it's actually you know, if you can find the video and link to it on YouTube Belinda Beck's lift more study It's just an awesome video to watch these Little old ladies walking around picking up, you know dead lifting their body weight and stuff like that Is there anything else you wanted to ask Jack or about your results or anything else? Any pressing questions you have? Yeah, nutrition would be a good one actually. Yeah, calcium, vitamin D, protein, everything that's going to support muscle mass as well

because that's the other thing that we found here. So we looked at your body fat percentage, again, in absolute terms not that high, but for your age pretty high, right? Because you're young, so you're at the 80th percentile for your age. And your visceral fat was at the 80th percentile for your age. And your visceral fat was at the 50th percentile for your age. So we don't really care that much about total body fat. We care a lot more about visceral fat. So the fact that your visceral fat was at the 50th percentile, visceral fat is the fat

that's around your organs. That's the more metabolically deranging, damaging fat. We have a very high standard. We want to see that below the 10th percentile. I'll hit pause on that for a second, but then to relay the next thing that we looked at was your muscle mass. So we looked at the total muscle mass in your arms and legs. That's called your appendicular lean mass.

And then we looked at the total fat-free mass in your body. And both of those put you at about the 20th percentile. So the first question I'm asking when I'm looking at these results is, are you adequately muscled or under-muscled? So I really want to see somebody above the 50th percentile in muscle mass. So you're under-muscled. The second thing I'm looking at is with the body fat percentage where it is, both in the visceral fat, is that to me, I call that overnourished.

Now, I don't have blood tests to see where you are metabolically, but I want those are what I call my three questions. Are you metabolically healthy or not? I need a blood test to see it. I suspect you are though based on your zone two. So, the fact that your fat oxidation was 0.77 grams per minute, very hard, and your fasting lactate was 0.5, which is also very good. So my bet is you are metabolically healthy.

We would have to do a bunch of blood tests to confirm that, but I bet you would be. But you are overnourished, meaning body fat is too high and visceral fat is too high, and you are undermuscled. Your ALMI and your FFMI are too low. So that immediately tells me, like, what do you need to be doing? You need to be eating more protein, fewer calories, more resistance training. You don't need to do any more cardio.

Like that's like oversimplification, but like that's your path forward. And the last question I had around, I think I've heard you speak about it before, but it's around like the potential of what your muscle mass can be. If you lift as a teenager versus if you start lifting in your 29, so if I start lifting at like 27, the potential is a lot less, right?

Is that true or is that? I'm not sure. I think genetics play a pretty big role in that. In other words, I think that your ceiling is probably more dictated by your genetics than it is the age at which you started. I think if you took someone who is just genetically wired to put on muscle and they don't start lifting until they're in their 20s, they're still going to put on a ton of muscle. I've been lifting weights my whole life since I was 13 years old.

I'm never going to be like a monster. Like it's just not going to happen. There's no chance I'm ever going to be on the stage of a bodybuilding contest. Okay. Yeah, that's just one thing that's like always haunted me. Well, haunted me in the last two years. Yeah, yeah, yeah. But again, you have to consider a bunch of variables as you're lifting. So are you training at the right intensity So are you training at the right intensity? Are you training at the right frequency?

Do you have the right selection of exercises? Is your technique correct? So lifting weights, it's not a uniform term. So you really have to dive into that, right? So to put on muscle, you probably need to be doing a minimum of 10, and I would say ideally closer to 20 sets per week per body group, the intensity has to be sufficient. So we were talking about that minimum two, ideally one rep in reserve per working set.

So if you're just doing like three sets of 10, but you could have done three more reps if you really pushed, there was no training stimulus there. I've got a question on that, which is linked to one of my friends, but it's something I've heard you say, which is you've said to me before that you struggled with gaining weight. Yes. A friend of mine has said this to me for the last 10 years.

A muscle. Yeah, so he says like, even when he eats a lot, he has to like, feels like he's force feeding himself and it's like not natural. And then when he goes to the gym, he hasn't seen the results. Whereas for me, I've never had the problem of like, I can eat loads, and then I go to the gym and I work out and muscle comes on.

So for those people that struggle with A, eating enough calories, and then they go to the gym and they don't feel like they're able to gain muscle, you've experienced this before, haven't you? You've experienced people that have said this to you? Sure. It's actually much more common with women than men, but it's focusing more on the protein as opposed to the total calories. You do need the calories, but it's probably breaking down the protein intake into smaller

servings. For many people, it just means they have to get shakes or things like that. They're not going to get it through Whole Foods all the time. I don't need to drink shakes because I'm able to get shakes or things like that. They're not going to get it through Whole Foods all the time. I don't need to drink shakes because I'm able to get protein through food enough, but that shouldn't be viewed as something you don't want to do. Even I'm sure some of the most successful bodybuilders in the world, just based on their protein requirements, still have to resort to shakes.

Figuring out what it takes to get one gram of protein per pound of body weight and making sure you get that even if it takes four servings a day, it should be the highest priority. And again, you don't need more calories at this point based on your visceral and body fat. We just need to make sure you're getting that gram of protein per pound of body weight and that you're getting the right training stimulus in the gym. OK.

Thank you. OK. Thank you for that the gym. Okay, thank you. Okay, thank you for that, Peter. I didn't know we were gonna be doing a little consult. Yeah, I know, but it's super fascinating. Even for me, even though they're not my results, I learned a ton about that. The question, we don't necessarily need to go through all of the results here for Jemima, but how do you see women's results being different,

typically, as it relates to bone density, muscle mass, and those things? I was wondering if even for the VO2 max you're expecting different results for women or? Well we score them on a different curve. So the results are going to be a little lower. And again, part of the reason is women have less muscle, all things equal. And muscle is the organ that is going to consume the most oxygen outside of the brain. If you took a woman at 25 and a man at 25, there's a different threshold for what the

grade is on the curve. But I would say the biggest difference we typically see is, and not so much at the ages of these guys because they're both so young and fit. But as we get into kind of older folks, we definitely see more of an issue with muscle mass in women and bone density in women. I was quite surprised with Jack when you talked about visceral fat. Yeah.

There's two types of fat that I've come to learn. Subcutaneous, which I think is on the outside. Yep. And then viscerals around the organs. Right, so the body fat is mostly measuring his subcutaneous fat. Oh, on the outside? Yeah. Okay.

I've got a little bit of subcutaneous fat right now. As we do all. How do I know if it's an issue or not? Unfortunately, it's very difficult to know without further investigation. I say this because I haven't been able to predict it looking at somebody. I've seen people who have lots of subcutaneous fat, but when you look at their liver and look at their visceral fat, they have virtually none, and they tend to be quite metabolically healthy.

Maybe aesthetically, they've got too much body fat, and there are lots of reasons why they might not want that, I'm sorry, based on excess body weight that just in general is an impediment to movement or pain in their knees or joints. But it's not actually causing them harm physiologically. And conversely, if you look at Jack, he actually looks pretty lean looking guy. Nobody would look at Jack and say he's overweight, but he's got a little bit too much fat on the inside and that if not, I mean, I think his running and his fitness is probably offsetting it metabolically. But there might become a day when that's not the case.

So it you know, this is something that I think just needs to be addressed. And again, people that are in their 20s can get away with a lot and it starts to become something you don't get away with in your 40s. Is there a genetic component to this? And also, what is caused it? What usually causes it? The body fat, the visceral fat? Visceral fat.

Yeah, there's definitely a genetic component to it. But the truth of the matter is the cause of this is just fuel partitioning. It's just where the body is putting excess energy. So all of the fat we have in our body comes down to where does our body choose to store excess energy? Because that's the only way we store it. We can't store protein. So we can only store when we store protein technically in muscles.

But we're basically storing carbohydrates and fat. So you can store carbohydrates preferably in the muscle and in the liver as glycogen, but that's a very finite source. So most of where you're storing those things is excess glucose gets stored as fat, and then fat gets stored as fat. So if theoretically Jack had a higher muscle mass, he would have less visceral fat potentially? Yeah, probably, because first of all, muscle is more metabolically active. So more metabolically active tissue means higher energy expenditure, which would all things equal mean lower fat.

That makes sense. And if there were a couple of things that I could do to reduce my visceral fat, we talked about exercise there, we talked about diet, intermittent fasting? Are you a fan of those kinds of things? There's no evidence that intermittent fasting produces any benefits above the equivalent amount of caloric restriction So, you know what whether you're eating in eight hours or six hours or across 12 hours if the same number of calories are consumed It's essentially producing the same outcome sleep stress Absolutely dramatic. Well, we've talked about sleep already. If your sleep is not good, you are going to be insulin resistant.

If you are insulin resistant, you are partitioning fuel in an unfavorable way, which in English means you are more likely to access glucose than access fat, even at low levels of intensity when you should be accessing fat. That's why, by the way, I thought he's probably still insulin sensitive based on how high his fat oxidation was. Meaning when he was at 165 beats per minute on a treadmill, he was pulling out almost 0.8 grams per minute of fat. That's really good. That tells me he fuel partitions well. He knows how to access fat when he of fat. That's really good. That tells me he fuel partitions well. He

knows how to access fat when he needs fat. So that's still working in his favor. But for many people, once they're exercising that hard, their fat oxidation goes to hell. And all they're doing is accessing glucose. But there could be a link for, in his case, between sleep and visceral fat. Yep. Especially if he travels with you. Yeah. And then alcohol. You mean Jack doesn't drink alcohol, but generally visceral fat and alcohol. Yeah. Bad sign.

I want to talk to you about this alcohol point because I saw Huberman tweet the other day saying that it's now pretty well established that even moderate alcohol intake is bad for you. But I sat here the other day with someone else who said to me that they talked about the Mediterranean diet, the Italians, they seem to be fine, etc. But I sat here the day with someone else who said to me that they talked about the Mediterranean diet, the Italians, they seem to be fine, et cetera. And I wanted to kind of get your perspective on whether small amounts of alcohol intake are okay or not. Because some people still think it's healthy to have moderate alcohol intake.

It's better for the heart. I think that is pretty abundantly not true. So I don't think I am aware of any real evidence, and we've scrutinized the heck out of this. So the subscribers to our podcast get these premium newsletters every month where we do an ultra insane deep dive into a topic, and alcohol was one of them. So this is like you're getting a treatise, a 20 page research report on a topic. So for anybody who's interested in that, they should go and get the alcohol piece. But the TLDR is that there is no compelling evidence whatsoever that there is a health benefit that comes from ethanol consumption.

The molecule of ethanol is not healthy at any dose and I believe that is unambiguously true. That said, it does not appear to be linearly toxic, meaning low, low doses, probably sub 15 grams per day. 15 grams of ethanol would be what you would get in a standard drink. Standard drink, not a generous drink. So you know, whatever, like three, four ounces of wine would be 15 grams of ethanol, 14

grams of ethanol. It appears that for most people, the toxicity of that amount of ethanol is very difficult to measure. And this is where you get into the area of for some people, there might actually be enough of a pro-social benefit from that amount of ethanol if consumed in an otherwise healthy environment. Right? So if you talk about the individual who comes home and has a glass of wine while he's with

his wife and they kind of unwind in the backyard and talk about their day and things like that, there might be benefits from doing that that outweigh the very, very small amount of toxicity that came in that ethanol. Once you reach about 30 grams of ethanol a day, I don't see and I have not seen a shred of evidence that there is any amount of prosocial behavior that can offset the toxicity of that ethanol. So while I would not go as far as the World Health Organization, which has condemned ethanol as a carcinogen, at every dose, I just don't see the data to make that case for every dose.

I tell my patients in a very measured, nuanced way kind of what I just told you. I drink alcohol, but I think about it every time I do. Is it worth it? Is it worth it? Is it worth it? I'm not just drinking for the sake of drinking. I have this expression, don't drink on airplanes because the alcohol sucks. Like, I'm not just drinking to numb myself, right? Like, if I'm going to drink,

there's a reason. It's going to be really freaking good. And that for me amounts to probably like four drinks a week. You're just talking about airplanes there. I was thinking about electrolytes. There's been a huge boom over the last couple of months, a year of people consuming more and more electrolytes. There's been a huge boom over the last couple of months and year of people consuming more and more electrolytes. Everyone's launching an electrolyte drink and consuming much more salt and sodium. What do you make of this? Are we electrolyte deficient? Well, first of all, as a disclosure, I'm an investor in a company that sells electrolytes,

so Elementee. So I'm an investor in that company, which I always want to disclose stuff like that if it's pertinent. The short answer is it depends. So why did I get interested in electrolytes? Well, I historically never consumed electrolytes when exercising. I was pretty much always consuming water and or water plus carbohydrate, depending on the intensity and duration of the exercise. I also tend to have very low blood pressure.

A couple of years ago, I had a really, really bad fall when I woke up in the morning and I was jet lagged. I had just flown to Brazil. Obviously, you get a little bit dehydrated on a plane and then the first … you get in whatever that night and then the next morning, I woke up, got out of bed and face planted into a table. You can probably still see the scar on my forehead. I get back home and my doc measures my blood pressure.

It's like 95 over 60. He's like, yeah, you're really dehydrated, man. We need to get a little more… It's not like I don't eat salt. I make zero effort to restrict sodium in my diet, but clearly I was just exercising too much, you know? I mean, especially living in Texas. Like, when I'm exercising outdoors, I'm sweating like crazy.

So it's like, you just got to get more salt, man. So I just went… I literally then did a super deep dive on hydration and realized that there's basically two ways to maximize hydration. Either you consume water with a high enough, not just a high enough, with the absolute correct concentration of glucose in it, and the correct concentration is between 5% and 6%. So that's 50 to 60 grams of glucose per liter of fluid will maximize water uptake through

the sodium water transporter, or you consume what's called osmotic sodium in water. Those are your two options, with the glucose one being slightly better. And so what I realized is, look, I don't exercise long enough anymore to justify it. And the only workout I do a week that is intense enough to justify it is that VO2 max one, where I actually am using glucose and water But for the rest of my workouts, I don't I don't need it I just need sodium and water and then I just went through every product on the market

Like literally went to Amazon click click click click click click click click order every one of them and realized at the end of the day It's a commodity product get the one that tastes the best because that's the one you're gonna have to suck down every day Peter what's the one you're going to have to suck down every day. Peter, what's the most important thing we didn't talk about that we should have talked about as it relates to your work, the science that you're obsessed with at the moment, and anything that my audience might and should need to know that we haven't yet discussed? Maybe just the idea that it's really tempting in the world I live in to want to find single sources of problems. There's always a boogeyman.

I think unfortunately, the entire landscape of health influencing and social media has created a very unhelpful narrative around many of these things. And so there's an effect called the Dunning-Kruger effect, which can be sort of put into a cartoon, where it shows experience on the x-axis and confidence on the y-axis. So you've seen this graph, I'm sure, where it starts out like it just skyrockets up to variance on the x-axis and confidence on the y-axis. You've seen this graph, I'm sure, where it starts out like it just skyrockets up to what's called the peak of stupidity, and then it comes down into the valley of humility.

As you become more and more of an expert, you gradually rise. This idea of the deeper you go out from shore, the further from shore, the deeper the water gets. Most of what I'm sure your audience is going to be exposed to, because we all are if we're on social media or whatever, is people preaching from the peak of Mount Stupidity. I think maybe the thing to be thinking about is what are the signs of that? It's usually people that are like, there's one thing that is the thing. It's this additive in food, or it's this particular oil food or it's this particular oil or it's this sugar or it's this, that.

And it's like the truth of the matter is it isn't one thing. It's really, really complicated and it's hard to talk about things that are complicated and we tend to just want to focus on one thing. And I've been guilty of this myself. If I look at stuff I was writing 15 years ago, I'm like, man, you really oversimplified that too much. Like, you overindexed on that and you ignored this thing. And so I just think that, you know, try to identify people out there who are talking

about things in a nuanced way, and you're generally going to be closer to the direction of reality. And how do you deal with that as a podcast host? Because you must sit there, you know so much about this subject matter, and you're generally going to be closer to the direction of reality. And how do you deal with that as a podcast host? Because you must sit there, you know so much about the subject matter, and you must sit there and hear people say to you on your podcast things that you don't agree with. Well, on my podcast it's easy because, again, the nature of my podcast is super inquisitive, so it's just very easy to push back.

And sometimes I don't, sometimes I'll... You know, I was recently interviewing somebody and they made a comment and I just knew it was wrong. But I was like, you know, I'll make an editorial comment later about this for the audience to understand that he's confusing cause and effect. And I didn't push back. And afterwards, I thought I probably should have. I probably should have pushed back on what he said a little bit.

But again, on my podcast, it's easy. I think the bigger issue is when people send me links to podcasts, like, what do you think of this? And I have to go through and like explain why what this person said is completely wrong. I mean, just completely unfounded in any scientific basis whatsoever. But they're a very compelling speaker. And so I get it. Like I get why, you know, that you would, you know, as my friend, send that to me with

concern. One of the things we've introduced recently, well, in the last three, four months is just we put, we have some independent scientific individuals who have a look at some of the things that are being said just to cross reference and provide context. We call it kind of context checking. Nice. Just because some of the bigger things, obviously there's so many big, as you were saying, so many terms like seed oils and this and this and this that have started a bit of a nutrition war on the internet. And so we just want to make sure that we provide more context to these things.

So that a person at home who isn't going to take it upon themselves to apply that context or do the research has more of a wide opinion. But it's difficult because, as you say, oftentimes it's the best speaker or the person with the most conviction that gets heard. You've managed to break through all of that and provide a tremendous amount of nuance and complexity to these subjects, but also to achieve the same focus and articulation and resonance and accessibility that some of those individuals have achieved. I would highly recommend anybody who has not read this book to read this book, because this is the book on this subject. And I say that I've

interviewed many hundreds of people, but this is the book on this subject. It's been a global phenomenon for all the reasons I've described about it being so accessible, so nuanced, but so easy for someone like me to understand, even though I'm not a scientist. And it's the book that I recommend to my friends, to my family, when they're trying to understand the subject matter of longevity in a world where there is just so much information. And that's why this book did so well. And it continues to do so unbelievably well. But I'd also recommend everybody to go check out your podcast, which I love watching. And also, if they want other resources from you, where do we send people, Peter? I think our website probably, so Peter Atiyah MD, the website will probably direct people

to all the different sort of places where we have unbelievable amounts of free information. So we have a newsletter that comes out every single week. It's free. It's really valuable people You know the open rate on that is through the roof because it's not junk Like it's it's we're putting something in your inbox every single Sunday that you're gonna want to read about the exact topics You're asking so I'm gonna link all of that below So all of the links below for Peter's work if you if you haven't become obsessed like we all are here with Peter's work

And I really mean that we're all massive fans of yours Jack was saying before you came, he said, I love Peter. You were saying this the other day, he was saying this about a week ago. And that's something that I think we all feel because of the impact you've had on our lives of demystifying this information, but bringing it to us in a way that's so, so accessible, so smart and so trustworthy. So Peter, thank you for what you're doing, because you're demystifying a very complicated world for all of us. And it's a world that if demystified, we stand a better chance of living happier, healthier, longer lives. And there's probably nothing more important to what makes life meaningful and fulfilling and me being

able to walk up and down those stairs in Bali when I'm 75. So thank you, Peter. It's tremendous, really, really tremendous. And I appreciate you very, very much. Peter, I was so caught up in admiration for you that I forgot that we have to ask you this question, which is the question left by the last guest. And that is, what would you do if you weren't afraid? Why that face? Oh, because I've been dealing with that for a long, I've been dealing with something for a couple of weeks that is incredibly frightening.

But I think I finally worked up the courage to do it. But I can't speak about it, unfortunately. Oh, really? At least not yet. I will be able to one day. There will be a day when I will be able to tell this story. And it will be one of the most important be able to tell this story and it will be one of the most important decisions I've ever made in my life.

Oh, I'm so curious and so intrigued. I can tell by your reaction that it's going to be profound for both you and all of us. I can tell by your reaction because I can tell that there's some element of struggle there. Whatever it is, best of luck and maybe we'll talk again in the future once you've been able to talk about it. I can't wait. Thank you, Peter. We launched these conversation cards and they sold out. And we launched them again and they sold out again.

We launched them again and they sold out again. Because people love playing these with colleagues at work, with friends at home, and also with family. And we've also got a big audience that use them as journal prompts. Every single time a guest comes on the diary of a CEO, they leave a question for the next guest in the diary. And I've sat here with some of the most incredible people in the world,

and they've left all of these questions in the diary. And I've ranked them from one to three in terms of the depth, one being a starter question. And level three, if you look on the back here, this is a level three, becomes a much deeper question that builds even more connection. If you turn the cards over and you scan that QR code, you can see who answered the card

and watch the video of them answering it in real time. So if you would like to get your hands on some of these conversation cards, go to thediary.com or look at the link in the description below. This has always blown my mind a little bit. 53% of you that listen to the show regularly haven't yet subscribed to the show. So could I ask you for a favour? If you like the show and you like what we do here and you want to support us, the free simple way that you can do just that is

by hitting the subscribe button. And my commitment to you is if you do that, then I'll do everything in my power, me and my team, to make sure that this show is better for you every single week. We'll listen to your feedback, we'll find the guests that you want me to speak to, and we'll continue to do what we do. Thank you so much. Thanks for watching!