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The Diary of a CEOThe Diary of a CEO

Harvard Professor: REVEALING The 7 Big LIES About Exercise, Sleep, Running, Cancer & Sugar!!!

In this new episode Steven sits down with the world renowned expert on the evolution of human physical activity, Dr Daniel E. Lieberman. 0:00 Intro 02:38 Why do you do this research? 03:35 Where has your work taken you? 04:34 Has your research shifted your perspective on exercise? 05:55 The biggest exercise myths 12:00 The importance of weight training 16:12 Why always moving your body is so important 19:47 Genetics vs lifestyle 24:20 Have we evolved to be lazy? 25:46 We should be preventing diseases, not medicating them 28:13 Do hunter-gatherers get the same diseases as us? 31:32 The truth about sugar 37:30 How would you redesign our society? 42:18 Should organisations force people to exercise? 48:25 What did you learn from these tribes? 50:03 Why you should do strength training on your feet 56:38 Is too much muscle bad? 01:01:46 Running myths 01:06:58 The best cardio workout 01:09:21 The best exercise for weight loss 01:15:59 Why we need more compassion around exercise 01:20:46 What is it that actually gets people exercising? 01:24:59 The last guest's question You can purchase Dr Lieberman’s newest book, ‘Exercised: The Science of Physical Activity, Rest and Health’, here: https://amzn.to/49udz2v My new book! 'The 33 Laws Of Business & Life' per order link: https://smarturl.it/DOACbook Join this channel to get access to perks: https://bit.ly/3Dpmgx5 Follow me: Instagram: http://bit.ly/3nIkGAZ Twitter: http://bit.ly/3ztHuHm Linkedin: https://bit.ly/41Fl95Q Telegram: http://bit.ly/3nJYxST Sponsors: Huel: https://g2ul0.app.link/G4RjcdKNKsb Airbnb: http://bit.ly/40TcyNr

Steven BartletthostDr Daniel E. Liebermanguest
Jul 10, 20231h 29mWatch on YouTube ↗

EVERY SPOKEN WORD

  1. 0:00 – 2:38

    Intro

    1. SB

      A lot of people exercise because they believe it will help them to lose fat.

    2. DL

      One of the biggest debates on the planet.

    3. SB

      What advice have you got for me?

    4. DL

      So this is not a well-known fact, but-

    5. SB

      Daniel Lieberman.

    6. DL

      He studies and teaches-

    7. SB

      ... how humans are supposed to live.

    8. DL

      Author and professor at Harvard University. Exercise. Disease.

    9. NA

      Sleep.

    10. DL

      Nutrition.

    11. SB

      He has the answers on all of those things that most of us care about.

    12. DL

      We evolved to be very physically active, working in the fields, hunting, gathering. But now we live in a world where only 50% of Americans ever exercise, and the rest of the world is headed our way. Cancers, depression, anxiety can attribute that to less physical activity. In fact, women who get a 150 minutes of physical activity a week have a 30 to 50% lower breast cancer risks. I mean, it's crazy, right? The problem is that we spend 3% of our medical budget on prevention, and yet 75% of the time, the disease is a preventable disease. It's a completely backward, stupid system.

    13. SB

      When you started writing this book about exercise, was there any instant changes that you implemented into your own life?

    14. DL

      Strength training. The more I study the importance of doing weights, especially as you age, the more I started kicking myself for being lazy about that. When people retire, they become less active. They tend to lose muscle, and then that starts off a vicious cycle.

    15. SB

      So would you say we shouldn't retire?

    16. DL

      Well, it's a very modern Western concept. And yes, we do pay a price for it.

    17. SB

      So how does one go from having a negative opinion towards exercise to becoming an exerciser?

    18. DL

      As an evolutionary biologist, there are multiple ways of doing that. So...

    19. SB

      Daniel, what are some of the biggest myths within exercise?

    20. DL

      Gosh, there are so many. One of the most common, of course, is ...

    21. SB

      Daniel Lieberman. He's been to every corner of the world, visiting native tribes to understand how humans are supposed to live. And now he has the answers on all of those things that most of us care about on sleep, nutrition, exercise, disease. You know, on disease, he says that 74% of them can be prevented, and he knows how to prevent them. Aging, running, are we born to run? He tells me this story of a CEO that forces his employees to exercise, and the impact that that's had on that company. And he talks about how as humans, we've evolved to either use it or lose it. So maybe, maybe retirement is a really bad idea for many of us. One of the most thought-provoking, pivotal conversations I've had on this show. You're really going to take a lot from this one. And I suspect, after listening, you'll probably start running too, for exercise, or from some of the decisions you've spent your life making.

  2. 2:38 – 3:35

    Why do you do this research?

    1. SB

      Daniel, your work is so, so incredibly im- impressive, reaches such an incredible depth, charters new territory, and it's been an unbelievable, clearly very passion-driven career you had. So my first question for you is, why are you doing this?

    2. DL

      (laughs) Um, it's a good question. Um, I, um, you know, I started off being obsessed by human evolution. I, ever since I was a kid, I was really interested in human evolution and f- I spent much of my early career working on skulls and heads and why they are the way they are. And then I kind of got involved in public health and issues of health and disease, kind of through the back door. I sort of slowly shifted my research trajectory towards studying the evolution of running, and then the evolution of physical activity and its relationship to health and disease. And, and I've become part of a movement that's often known as evolutionary medicine, which is how to apply evolutionary theory and data to issues of health and disease.

  3. 3:35 – 4:34

    Where has your work taken you?

    1. DL

    2. SB

      Evolutionary medicine. I've never heard that term before, but I love it. Where has your work on evolutionary medicine, let's call it, where has that taken you? Where, where has it taken you to learn, to research, to study?

    3. DL

      You know, so much of what we think about in terms of health and disease comes from a tiny fragment of the world's population. Almost entirely, like 90% of all the medical information comes from people from the United States, Canada, Europe, and Australia. So in order to, to study how bodies really work and how our bodies evolved to be, you have to leave, uh, places like Boston, where I live, and go to places like Africa or Mexico or wherever, to look at, at, at other populations and look at how those populations are transitioning to, to lifestyles like mine. And so, uh, we've been working in Kenya, um, for the last 15 years or so, um, and I've traveled some other parts of the world as well. India, you know, to kind of collect some data, but, uh, but mostly in, mostly in Africa.

  4. 4:34 – 5:55

    Has your research shifted your perspective on exercise?

    1. DL

    2. SB

      After doing all of this work, and after taking in all of this information, how has it shifted your perspective on running, exercise more broadly? What, have there been any sort of significant cognitive perception changes, you know?

    3. DL

      Yeah. Um, I actually had a, I mean, it doesn't happen very often, but I had kind of an epiphany moment, um, when I was working in, uh, Mexico. We were collecting data on the Tarahumara, very, also famous for their long distance running. And, uh, there was this elderly guy, he's about 70 something years old, and he's famous for his distance running. And I was asking him how he trained, and I had asked this question of a whole bunch of other people, and the translator I was working with was always struggling to ask that question because it turns out there's no word for training in, in that language. The concept of training doesn't exist. So, so, so she was trying to explain to this guy what my question was, um, and I could, even without a translator I could figure out just from his tone of voice, he was like, "Why would anybody run if you didn't have to?" And I suddenly realized, yeah, of course, exercise is a very weird thing, right? If you're, if you're a farmer and you're working super hard every day in the fields without machines and whatever, or if you're a hunter-gatherer and you're walking, you know, you know, five to 10 miles a day and digging and throwing, you know, doing all kinds of hard work and you're barely getting enough, enough food, why on earth would you go for a needless five-mile run in the morning? I mean, it's crazy, right?

  5. 5:55 – 12:00

    The biggest exercise myths

    1. DL

    2. SB

      The most viewed videos of yours, and the most viewed moments in those videos, address one question. Do you, do you have any idea what it might be?

    3. DL

      No, actually.

    4. SB

      ... the biggest myths in exercise.

    5. DL

      Right.

    6. SB

      And I think you actually pointed out one there with the, um, insight you got in Mexico. The way we exercise, going to gyms, practicing, is the natural or human, but evidently it's, it's a consequence of the privilege of our lives and the comfort we have of not having to seek out our, our dinner every day. What are some of the other biggest r- uh, myths with- within exercise that, um, you've come across in writing this book?

    7. DL

      Gosh, there are so many. (laughs) I had to actually limit, limit it to ten.

    8. SB

      Mmm.

    9. DL

      So I think, um, if you wanna understand physical activity and exercise, you also have to understand inactivity. And I think one of the biggest myths out there is that you need eight hours of sleep a night, um, and that sitting is the new smoking. You know, that- that basically... And I- if you, if you think about those two different myths, uh, why is it that we're constantly told to sleep more and to sit less? Actually, it's kind- it seems a little contradictory to me, right?

    10. SB

      (laughs)

    11. DL

      And it turns out that, um, um, that let's take sitting first. So, um, you know, there are all these, uh, you know, these slogans like, "Sitting is the new smoking," and, "It's really bad for you." And, you know, every time you sit in your chair, you lose two hours of your life, and you know, whatever. Uh, turns out that, um, all animals sit, right? My dog sits, um, cows sit, chickens sit, every animal sits. And hunter-gatherers also sit. In fact, if you, uh, some of my students actually put sensors on hunter-gatherers, and, uh, I- and we're doing some research in farmers as well, but they sit just as much as Westerners. Um, uh, so sitting is- there's nothing special about being, uh, t- about today's life, it's sitting. So it's that we sit all day long and don't do anything when we're not sitting, right? So if you... Uh, a- and furthermore, the, the big distance- difference is not so much how much we sit, but how, how we sit. So, turns out that people who, um, if you get up every once in a while, right? F- interrupted sitting is actually much more healthy than non-interrupted sitting for the same amount of time. So in other words, two people might... Uh, in, in the West, people sit for an average about 40 minutes at a- at about, whereas hunter-gatherers, for example, or farmers in Africa where we work, get up every about 10, 15 minutes. And when you do that, you actually, it's like turning on the engine of your car, you know, drive it around the block. You're, you're, you're, you're, um, you're turning on all kinds of cellular mechanisms, you lower blood sugar levels, you, y- all kinds of genes get activated, and it turns out that that is by far the most important, um, uh, way to, way to sit. So just get up every once in a while. Just pee frequently, make a cup of tea, you know, pet your dog, whatever.

    12. SB

      I think- thinking when I'm on planes and I've got a long flight, like, just-

    13. DL

      Yeah. I always sit in the aisle, right? So I can get up a lot always.

    14. SB

      Ah.

    15. DL

      And, um...

    16. SB

      What, what about sleep then?

    17. DL

      So sleep is another interesting one. So this idea that, you know, um, that we need eight hours of sleep has been around for a long time. It's been around basically since the Industrial Revolution. Um, but, um, if you actually... So, so colleagues in my field, so in evolutionary medicine, have put sensors on people who don't have, have all the things that we're told have destroyed sleep. So think about it, we're told that TV, and lights, and, and, uh, you know, our phones, and all these things are, are preventing us from sleeping. You know? Edison destroyed sleep, right? Uh, so (laughs) , so when you put sensors on people who don't have any electricity, and they don't have TVs, and they have- don't have phones, and they don't have, have, uh, any of these gadgetry, right? Electricity, uh, they... Uh, turns out they sleep like six to seven hours a night, um, and, um, they, uh, and they don't nap. Um, so this idea that natural human beings sleep eight hours a night is just, is just nonsense. It's just not true. And furthermore, when you start looking at the data, seven hours, if you actually look at, if you graph sort of how many hours a night you sleep on the X-axis, and sort of, uh, you know, some outcome like cardiovascular disease, or just h- how likely you are to die, it's kind of a U-shaped curve. So people who don't get much sleep are, are in trouble. Um, but the bottom of that curve is pretty much always about seven hours. So people actually do better if they sleep seven hours rather than eight hours. And yet we're told that if you don't sleep eight hours, there's something wrong, right? You're-

    18. SB

      Oh, so you can oversleep? (laughs)

    19. DL

      Well, yeah. I mean, there's also some complexity to this too, because of course, people who are ill might be sleeping more.

    20. SB

      Ah, okay.

    21. DL

      And so there's some, there's some biases that creep into the- how you analyze the data. But, but basically, it turns out that seven is, for most people, optimal. But there's a lot of variation, right, in everything. You know, teenagers sleep more, older people sleep less, it's complicated.

    22. SB

      One of the things that... Popular in culture as well is this idea of doing 10,000 steps a day.

    23. DL

      Yeah. Now that's fun. You know, that started because of a Japanese podomet- pedometer. Um, so, but right before the, the Olympics were in Tokyo in the, in the '60s, uh, they had invented the pedometer. And they were in a- sitting in a boardroom, and they were discussing what to call the pedometer, and they picked... Out of just, out of the blue, they picked 10,000 steps because that's apparently an auspicious number, and it sounded about right. There was no science behind it. Interestingly, it turns out i- it's pretty good, um, if you ac- if you look at, at steps per day and health outcomes. Um, your average hunter-gatherer, um, walks between 10 to 18,000 steps. Depends on male, female, et cetera. And, and if you look at steps per day and, and outcomes, um, um, right around 7 to 8,000 steps, the curve kind of bottoms out, right? There's- doesn't seem to be a huge advantage to taking more than that per day in terms of, you know, large epidemiological studies. So, turns out to be not that bad a goal, but it's not a... There's no... It's not a perfect number, like a lot of things, right? It's just a kind of a... It's a reasonable, it's a reasonable goal to shoot for.

    24. SB

      When you, um, when you started writing this, this book about exercise and running and all these subject matters, was there any r- instant changes or any real lasting changes that you implemented into your own life from everything you'd learned? I, I think about that all the time with this podcast. I'll have a guest on, I'll have these mini Eureka moments, and then something will stick. So I'm, I'm wondering, having studied all, all of these people all

  6. 12:00 – 16:12

    The importance of weight training

    1. SB

      around the world and looked at their bodies and exercise and physical exertion, what have you taken into your own life that has stuck?

    2. DL

      I would say that I've become more serious about doing some strength training. You know, I, I've always loved walking and running, and you know, endurance kinds of activities, and I've always sort of hated doing weights, you know. I just don't like it, and I'm- I'm- I'm a c- I'm a wimp, you know? I'm not a very well ... (laughs) I'm a- I'm not a very strong person, and uh, you know, people tend to do what they like, right? You get reinforcement from it, and uh, the more I study the importance of resistance training and the more I study the importance of doing weights, especially as you age, um, the more I've uh, the more I re- I started kicking myself for- for being, uh, being lazy about that. So now I try to do good two strength workouts out of every week, at least, and uh, and take it more seriously. Because especially as you age, loss of muscle mass can be really debilitating. There's a, um, the technical term for that is sarcopenia. Sarco is- is the Greek word for muscle and penia is loss, so muscle loss. So as people get older, they tend to lose muscle, and when you do that, you become frail, and you lose functional capacity, and then that starts off a vicious cycle, right? Once that happens, then you'll be less likely to be physically active, and then of course when you're less physically active, your muscles begin to waste away more, and uh, it's very debilitating. And so I think as we get older, and I'm getting older (laughs) , it's more and more important, you know, to- to kind of incorporate that. So I think that's the one thing that I've- I've taken to heart.

    3. SB

      Yeah. From what you said there, it sounds like not doing resistance training, not doing ... not lifting weights as you age almost accelerates aging in- in any sort of superficial sense. What ... But it also s- in a physiological sense, you're- you're increasing the speed of aging.

    4. DL

      Yeah. I'm not sure if I'd think about it that way. But it ... I think it though ... I'd- I'd kind of reverse it slightly, which is that, you know, aging is just the clock ticking on, right?

    5. SB

      Mm-hmm.

    6. DL

      There's nothing we can do about age. But senescence is the way- is the way our bodies degrade as we get older, and what physical activity does, in fact may be the most important thing about physical activity, is that it slows senescence, especially for certain organs and systems. And there are different kinds of physical activities, so there's endurance physical activities, you know, like running, walking, et cetera, swimming, and then strength or resistance physical activities, and they have different kinds of ways in which they slow various properties of senescence, which we, you know, colloquially call aging, and all of them are important. And- and I think one of the things that's really interesting about humans, in fact I think it may be the most important thing about this book, and you asked about myths earlier, the most important myth, I think, by far, is this idea that as you get older, it's normal to be less active, and that is just not true. Um, we evolved to be grandparents. We evolved to live ... Uh, one of the things that's most interesting about humans maybe, is that we evolved to live about 20 years or so after we stop reproducing. No other animal does that, except- except orcas, maybe killer whales. But with the exception of killer whales (laughs) , humans have this really weird life history. We li- we- we- we evolved to be grandparents, but grandparents in the old days weren't, you know, retiring to Florida or I don't know where they d- what they do in England or whatever, go to Majorca or whatever-

    7. SB

      Hmm.

    8. DL

      ... and you know, kick up their heels and play golf or whatever with carts. Grandparents in the- in the olden days, right, and- or in m- in many cultures still today, are working, right? They're working in the fields, they're hunting, they're gathering, they're getting food for their children and their grandchildren, they're helping with childcare, and that physical activity is, you know, that- that's what their job is to be physically active. But in turn, that physical activity turns on an amazing suite of- of- of- of physiological processes that counter aging, turns on repair and maintenance processes that not only keep our muscles strong, but also keep our DNA from accr- accruing mutations, keep our mitochondria numbers high, keep um, keep our- the cells in our brain from accumulating gunk, uh, so that prevents Alzheimer's and other forms of dementia. I mean, for almo- for every system of the body, physical activity has- has benefits that slow the aging process, and so when you stop doing it, you acceler ... E- and that's the way in which you ... It perce ... You perceive it as accelerating aging. But really, it's the absence of physical activity which lets aging run amok.

  7. 16:12 – 19:47

    Why always moving your body is so important

    1. SB

      In your first book in 2013, The Story of the Human Body, in chapter 12, you said, um, you used this phrase, "Use it or lose it," basically. We- we evolved to use or lose our bodies. And I was sat with, um, someone recently, and I was trying to figure out why it appears that when people retire, or the other instance I've seen is when their- their p- elderly partner passes away, it appears as if they don't live much longer.

    2. DL

      Yeah.

    3. SB

      It's kind of like f- kind of folklore or something that once you retire, your days are kind of numbered.

    4. DL

      Yeah. Yeah.

    5. SB

      And I- uh, I was trying to figure out the evolutionary reason for that, but it sounds like it's kind of what you've explained there.

    6. DL

      Well, I mean, I think part of that is, um, is- is depression, right? Um, um, when- when you lose a partner, I mean, grief and depression, your cortisol levels go up, your immune system goes down. I mean, you know, it's- it's-

    7. SB

      Uh-huh.

    8. DL

      ... it's really tough on your body. I mean, psychosocial stress plays a serious physiological toll. But- but also as you just pointed out, when people retire, they become less active, and that- that loss of activity has enormous effects on every aspect of our- our- of our- of our body, I mean, the ... And our bre- and our minds. I mean, physical activity is important not just for physical health, but also vital for mental health, and um, and I think a lot of the problems that, um, a lot of mental health issues we have today, depression, anxiety, uh, some of them, you know, to some extent, uh, we can attribute that to loss- to less physical activity. And as people age, l- becoming less physically active, again, makes them much more vulnerable to a wide sweep of diseases.

    9. SB

      So would you say we shouldn't retire?

    10. DL

      Well, or if you do retire, I mean, retiring is a, again, another modern weird thing, right? Nobody retired in the past. I mean, if you're a farmer, it's like a subsistence farmer in name it, any place, right, it's not like suddenly you hit 65 and all of a sudden you no longer have to work in the fields. You work in the fields until you're, you know, until you're dead, right? And hunter-gatherers don't retire. They- they continue to be physically active until- until they die, right, or till they get too sick. So it's a very modern Western concept, um, and um, and yes, we do pay a price for it. But you of course can replace-... you know, work that you do with- with- with challenging, rewarding, fun things to do. The important thing is just not to- not to stop being physically active. One of my favorite studies ever published, without a doubt, um, is- is a- is a study done by a guy named Ralph Paffenbarger. He realized that, uh, places like Harvard are fantastic for studying aging, because, um, Harvard, like other p- private universities, never lets go of their alumni. So, until you- the day you die, they're asking you for money-

    11. SB

      (laughs)

    12. DL

      ... on a regular basis. And- and so their, um, um ... And so he- he got the alumni association there, the Harvard Development Office, to let him follow a series of Harvard alumni from several years and can keep asking them d- d- questions about their physical activity levels, and also their diet and whether they smoked and stuff like that. And then he tracked them for 25, 30 years. And what he found was that the alumni, w- after you corrected for every factor you could think of, that as y- as the alumni got older, the effect of physical activity on their health outcomes was bigger and bigger. So, alumni who were in their 20s, 30s, and 40s, for example, who were- were exercising, you know, four or five times a week, they had about 20% lower death rates. By the time t- they got to their 60s and 70s, the alumni who were exercising more had 50% lower death rates. So as you get older ... So what ... And this has been replicated, again, many times, but what he showed was that as you get older, exercise becomes more, not less important, for maintaining your health.

  8. 19:47 – 24:20

    Genetics vs lifestyle

    1. DL

    2. SB

      Been thinking a lot about this 'cause I was- I was saying to Jack, my dad is 60-ish, but he's very, very out of shape. Very, very out of shape. And I was in, um, I was in Indonesia and I was with my girlfriend, and we went and we were going white wa- water rafting, so we had to go down this really big h- hill. And with all these stairs, it was like 300 meters of stairs, and I remember of just thinking, "My- my dad wouldn't be able to do this w- at his age, at 60, and I want to be able to go down those stairs when I'm his age," because at the bottom of there was a fun activity with someone I loved. And to think that I'll get to a point in my life where, not so far away in the grand scheme of things, um, where I won't be able to go up or down some stairs because I'm 60, um, because of my sort of genetic predisposition, as I saw it, was quite- was quite sad. But having heard you say that, it's really- feels much more like a choice than it is genetics.

    3. DL

      Yeah. Well, we have this expression in my field, which is that genes load the gun and environment pulls the trigger, right? Some of us have genetic presi- predispositions towards being, you know, more likely to get diabetes, or heart disease, or this or that or the other. But our great-great-great grandparents, in different environments, weren't getting these diseases, or they were getting them at much, much, much lower frequencies. And it's not because they were dying earlier. It's because these diseases were mor- less common. So, I think we too often blame our genes for, uh, many of these- these- these diseases, um, or many of these health problems, um, and it's- I'm not in any way denying the role of genetics, i- but that environment is way more important. And we have control over our environment, to some extent. And so, if you wanna reduce your risk of cardiovascular disease, reduce your risk of diabetes, reduce your risk of Alzheimer's, dementia, y- y- m- exercise isn't a magic bullet. It's not gonna prevent you from getting those diseases completely, but it lowers your risk, uh, quite- quite- quite substantially. And we know why, too. I mean, we have an immense amount of data on why that's the case, um. A- for every single one of these diseases, we understand the mechanisms by which physical activity has, uh, you know, important mechanistic effects on- on these diseases. So it's- there's epidemiological data, there's mechanistic data, there's personal data. The problem is that it's hard to do, right? It's- it takes willpower to, um, overcome the- the- the- the inertia of- of- of- of doing what's completely normal, which is wanting to take it easy, right? I was- I was just, you know, I just flew yesterday from Denver to Boston, and in the- and they- in the- in the airport, you know, there are these escalators right next to the stairway, right?

    4. SB

      Mm-hmm.

    5. DL

      And- and- and- and, um, the escalator and the stair- it wasn't a huge stairway, and everybody's lining up to take the escalator, and like the stairs are totally free. So I, r- being me, I a- of course I can't all- I'm not allowed to take the escalator unless, you know, I have to, right? So I, I run up the stairs, but you know, it's- but those people taking the escalator, there's nothing wrong with them. There's- they're not lazy. It's just an instinct, right? It's an instinct to take- to take it easy when you can, right? 'Cause when- and we now live in a world where everybody can do that, right? Because we have escalators and- and lifts and cars and shopping carts and all these wonderful devices to make our lives easier, and now you have to overcome this fundamental basic instinct to take it easy in order to be physically active. And that's basically what exercise is. And so ... And- and furthermore, if you're out of- if you're unfit and you're not really, you know, exercising isn't any fun, right? It's- it's- it's- it's unpleasant. You, you know, you sweat and you get hot and you get cranky and, you know, um, and- and it's not that rewarding, uh, until you get fit. And so, uh, people hate it, right? Um, and, uh, and then we blame them for being lazy. But they're actually just being- they're just being normal, and I think we need to have more compassion towards- towards people who struggle to exercise.

    6. SB

      Quick one before we get back to this episode, just give me 30 seconds of your time. Two things I wanted to say. The first thing is a huge thank you for listening and tuning into the show week after week. It means the world to all of us, and this really is a dream that we absolutely never had and couldn't have imagined getting to this place. But secondly, it's a dream where we feel like we're only just getting started. And if you enjoy what we do here, please join the 24% of people who watch this channel regularly and have hit that subscribe button. It means more than I can say. And if you hit that subscribe button, here's a promise I'm gonna make to you. I'm gonna do everything in my power to make this show as good as I can, now and into the future. We're gonna deliver the guests that you want me to speak to, and we're gonna continue to keep doing all of the things you love about this show. Thank you. Thank you so much. Back to the episode.

  9. 24:20 – 25:46

    Have we evolved to be lazy?

    1. SB

      This basic instinct to take it easy...Are we evolved to be lazy? Take escalated riders?

    2. DL

      Well, I wouldn't use the word lazy, but we are evolved to take it easy, to, to rest whenever possible, right?

    3. SB

      So we've now got ourselves into a bit of a comfort crisis here, because everything has, in our lives is optimizing u- us for convenience and ease.

    4. DL

      Right. Right. And well, it's also c- it's, it sells, right? I mean, comfort, I mean, I mean who prefers to sit in economy as opposed to business class, right? Nobody, right? Comfort is nice, right? Who prefers shoes that are uncomfortable, right? We, we, we, you know, comforts, comforts, you know, we, we love comfort, right? But since when is comfort necessarily better for you, right? I mean, are comfortable shoes actually better for you than going barefoot? Are the comfortable chairs better for you than, or taking the, the lift better for you than taking the stairs?

    5. SB

      It is in the short term, or at least it appears to be today. (laughs)

    6. DL

      Right. Yes, because we often value the short-term benefit over the long-term cost, right? Um, that's hyperbolic discounting is the technical term for that. But, but, um, so we, you know, we live in a world where, where we, we, we, you know, we pay extra for, for comfort, or we, and we'll, we'll prefer it. But, um, but now we also live in a world where we have to now go out of our way to be physically active because it's no longer necessary. And so again, I go back to my original statement, which is that people evolve to be physically active for two reasons and two reasons only, when it's necessary and rewarding. When we don't make it necessary, we need to figure out ways to make it rewarding. And, and that's hard. It's very hard.

  10. 25:46 – 28:13

    We should be preventing diseases, not medicating them

    1. DL

    2. SB

      Making it rewarding. So one way that you might make something rewarding is by looking at the stick, and then the other side is maybe the carrot. But just looking at the stick then, you were going through a series of diseases a second ago, Alzheimer's, um, high blood pressure, all of these kinds of things, cardiovascular diseases. I almost think we've come to assume that these are inevitabilities of life.

    3. DL

      Yeah.

    4. SB

      We'll get cancer.

    5. DL

      Yeah.

    6. SB

      One of us will get...

    7. DL

      Yeah.

    8. SB

      Someone in here is gonna get Alzheimer's, and that's the way we live. So we're, we're, we're preparing to medicate when that day comes-

    9. DL

      That's right.

    10. SB

      ...that I get, God forbid, diagnosed with something.

    11. DL

      That's absolutely right. In fact, that's what medical students today are taught, right? If you go to medical school today, you are taught that as people get older, their blood pressure goes up. I can tell you that's just not true. It's in the Western world where people are physically inactive and eat crap diets that their blood pressure tends to go up. But there are plenty of people, I'm actually one of them, right? Who don't have high blood pressure as they age. And guess, (laughs) what's the best way to prevent getting high blood pressure as you age? It's, um, you know, I sound like a broken record, but we have this idea that as you get older, yes, you're gonna, you're... And we're lucky, right? You know, because we don't die from smallpox when we're 30. We're lucky to get cancer when we're 60, right? What we've done is we've confused diseases that are more common with aging, with age being a cause of those diseases in the first place. And they're not inevitable di- inevitable diseases. Um, and many of them are preventable. And, and the problem is that in our society, we, we don't value prevention very much. We, we may talk about it, but we don't really put our money where our mouth is, right? In the US, which is arguably one of the worst healthcare systems... It is the worst healthcare system among the industrialized Western world, we spend approximately 3% of our budget, our medical budget on prevention. And yet when people walk into a doctor's office, 75% of the time, the disease is, according to the Center for Disease Control, a preventable disease. So we essentially spend nothing to prevent diseases that overwhelm our system and cause enormous amounts of misery. It's a completely backward, stupid system. And so, and, and the good news is it's not that hard to prevent a lot of these things. Um, um, it takes willpower and, um, it takes education and it takes access to, to good quality food and whatever. Um, but, um, uh, so in, in the one sense, it's very depressing, on the other hand, the optimist in me says, you know, we really can do something. And people who, even if without, even if they're not wealthy or whatever, I mean, there are simple things that everybody can do to improve their health outcomes.

  11. 28:13 – 31:32

    Do hunter-gatherers get the same diseases as us?

    1. DL

    2. SB

      These diseases we, we encounter today as we age and just generally in our society, when you look at hunter-gatherer, hunter-gatherer communities or you look at certain tribes around the world, maybe in Africa, do you see the same, um, the same types of diseases in the same, um, occurrence, level of occurrence? Or is there some diseases which just don't like... I'm, I'm wondering if, like, if... 'cause you know, cancer seems to be so popular for ex- as, as a disease and Alzheimer's and these kinds of things. So I wonder, has that always been the case throughout human history, and is that the case in other parts of the world?

    3. DL

      It is such a good question. So first of all, some of these, some of these diseases are really hard to s- to measure in non-Western populations because we don't have the diagnostic tools. So nobody really knows how common cancer is in, in, in a lot of parts of the world, right? There's just no... the data don't exist. That said, when you make estimates and you do look at the studies that are out there, and even if you look in, in, in historical records in, in places like Europe where people have been keeping track of this, there is no question that cancer rates have been rising and that cancer rates are much, much more common in the Western world. There's a strong association between cancer and wealth. And that's because cancer is basically a disease of energy, right? When your cells... 'cause cancer is basically natural selection gone awry in the body. It's when cells start competing with each other, uh, in ways that, uh, that cause e- basically and, and start, you know, going, you know, multiplying and dividing out of control, right? It's a kind of natural selection. And what is it that those cells are doing? They're competing for energy, and when you have more energy, like when you're eating more and being less physically active, you can, you basically feed those cells. So, um, so cancer... so, uh, high levels of insulin. Insulin is highly, uh, related to, to cancer. High insulin levels are, are carcinogenic. Um, high levels of, of body... of, of energy, you c- cause women, for example, to increase the, the amount of estrogen and progesterone that they produce. Men produce more testosterone. These are, and these are, these are mo- hormones that, um, of course are for, good for reproduction, but they're... but again, we evo- we evolved to be... to have as many babies as possible, right? But that doesn't mean-... that translates into health, right? So more estrogen, more progesterone increases risks of, say, breast cancer. More testosterone increases the risk of prostate cancer. So if you look at most diseases, right, people who are more physically active, they have lower levels of estrogen, progesterone, testosterone. They have lower levels of insulin. They have lower levels of blood sugar. All of these depress cancer rates and on average, people who are physically active have much lower rates of almost every single kind of cancer that you can think of. Women who walk 150, you know, get 150 minutes of physical activity a week have on average about 30 to 50% lower lifetime breast cancer risks than people who are sedentary. And yet for some reason, this is not a well-known fact. Um, and, and we under- we have, we have epidemiological data, we have mechanistic data, we understand how and why it works, and yet, and yet how often do you hear about cancer prevention? We talk about treating cancer, which is all important. If I get cancer, I would like it treated too, thank you very much. But why don't we spend more energy and activity and, and, and have more education about how to prevent cancers in the first place?

    4. SB

      Physical

  12. 31:32 – 37:30

    The truth about sugar

    1. SB

      active. I've n- I mean, I've never had that before, so that's, that's really helped me, um, to add more value to exercise in my mind. You were talking there about insulin levels and how that has ... There's a link between your insulin levels and your chances of getting cancer. Sugar, glucose, inflammation.

    2. DL

      Bad. (laughs) Yeah. I mean, I mean, look, if you wanna, if you wanna take ... Like, the three things you should, you know, if you really care about your health, don't smoke, right? That's kind of obvious. I think everybody knows that. Get some exercise. I don't think you need me to tell you that, right? And, and cut down on sugar, on foods that are high in sugar and low in fiber, right? That, you know, what we call high-glycemic foods. Those are the foods that elevate your, your, your, your blood glucose levels, your, your insulin levels shoot up. And insulin, insulin, the basic function of insulin is, is to, it's, it's, it's what we call an ana- anabolic hormone. It's, its job is to gr- is to store energy, right?

    3. SB

      Glucose?

    4. DL

      Glucose, but also fat.

    5. SB

      Okay.

    6. DL

      All right?

    7. SB

      S- okay.

    8. DL

      So ins- insulin, what insulin does is to get energy into cells.

    9. SB

      So it's like a taxi. It's like an Uber.

    10. DL

      It's like a taxi, yeah. Well, I mean, it, it's not a ta- it's like a, it's telling other cells to do that. So insulin, for example, binds to other cells that are the actual taxis.

    11. SB

      Okay.

    12. DL

      So it's like ca- it's like calling the Uber, I would say-

    13. SB

      Okay.

    14. DL

      ... say maybe, right? Um, and, um, and insulin is, is, you know, it's the funda- So when you, when you eat food, insulin levels go up, because it's job is to store that energy. And when you exercise, insulin levels go down because, because you wanna then use that energy, right? So, so, uh, so when cells get more energy, they're more prone to going out of control basically. And, and i- and, and inflammation is caused by basically by getting s- the... You store so much fat in your cells that those fat cells start to swell. And when those starts to swell, like anything, right, they start to rupture, they get damaged. And that damage attracts the immune system and the immune system gets turned on and that causes inflammation. So, so too much adiposity, too much fat s- you know, over-swollen fat cells is the, is a primary cause of systemic inflammation. And inflammation is like this slow burn in our bodies that causes widespread damage to pretty much everything you can think of. And it turns out that, so the two ways to deal with inflammation are one, to prevent it, right? So don't eat foods that are pro-inflammatory.

    15. SB

      Like?

    16. DL

      Anything with a lot of sugar basically, right? Th- I mean, that, you know, sugar is highly inflammatory or trans fats are highly inflammatory. But also, turns out, many people don't know this, but you also wanna turn down your immune system, right? You wanna turn the dial down. And I don't know, just give you one guess what it is that does that?

    17. SB

      Exercise.

    18. DL

      Exercise. And there, and, and, and the way it does that is that when you, when you're physically active, you're using your muscle cells. It turns out muscles are also an endocrine organ. Your muscles are producing a molecule called interleukin-6, IL-6, that in low levels is pro-inflammatory but at high levels it's actually anti-inflammatory. It turns down inflammation. And your muscles, because a third of your body is muscle, right, when you go for a run or, or a swim or a bike ride or whatever, you're producing a ton of this stuff and it turns down levels of inflammation. So people who are physically active, even if they're overweight, are actually controlling and regulating their inflammation. We never evolved to regulate inflammation because, in this way, because we never evolved to be physically inactive. Until recently, nobody was physically inactive, until they, unless they were dying, right? So, so we never evolved an alternative mechanism to regulate our inflammation other than physical activity.

    19. SB

      And we didn't live in a world with this much sugar.

    20. DL

      We never lived in a wor- (laughs) I mean, it's astonishing. You have, you pay more money for foods today that have less sugar added.

    21. SB

      (laughs)

    22. DL

      Right? I mean, that's just ridiculous, right? Because it's so cheap. And sugar is pr- you know, we love, everybody loves sugar. I mean, I've, um, I've gone hunting with, um, hunter-gatherers, you know, you know foraging with hunter-gatherers.

    23. SB

      Oh, really?

    24. DL

      And, um, and I can tell you that they're honey addicts, right? I mean, I've gone out with these guys and they go from h- You know, if they, if they fail in their hunt, like by 10 or 11 if you haven't killed an animal, you know, that's it for the day, right? And then it come, it, it turns from being a hunting expedition to a honey collecting expedition. And they'll go from hive to hive to hive, get smoke, burn out the bees, and just gorge themselves on more honey than I could possibly imagine to eat. Except these are lean, physically active hunter-gatherers and they, they handle it just fine. Um, but it's, you know, it's the, it's the Paleolithic equivalent of, you know, eating MARS Bars all day long.

    25. SB

      But they've been out doing physical activity for how long? Th-

    26. DL

      Yeah, I mean, the average day is about 15 kilometers of, of walking with some running. Yeah. So, so, so they're, you know, they can, they can, they can cope with it.

    27. SB

      How many hours is that?

    28. DL

      Oh, that's two to three hours probably.

    29. SB

      Okay. So from that, I-

    30. DL

      (clears throat)

  13. 37:30 – 42:18

    How would you redesign our society?

    1. DL

      to get the benefits.

    2. SB

      This is, uh... I've asked a few people this question, I don't think everyone's... anyone's really answered it, um, but I suspect you might be able to. If, if you were responsible for redesigning the nature o- of our modern world to make it more matched and less mismatched, what are some of the first things you would do to help society benefit in terms of our happiness and our health? I, I think about this all the time. I... 'Cause w- w- we don't seem to be turning around. We seem to be hurtling in a direction, kind of unconsciously towards artificial intelligence and moving less and being more sed- sedentary and taking pills more to fix everything. Lonelier than ever before. And again, h- you know, if we were to redesign it, blank canvas, piece of paper.

    3. DL

      It's a tough question because, um, we've essentially given ourselves what we want, right? Um, I can go into a supermarket and, I mean, I can do something that's unimaginable until recently. I can have, I can, I can have basically anything I want. I can eat better than the King of France, you know, a few generations ago. I can, I, I can... I'm here where... Like in New York, I... There's like every cuisine possibly available to me. I, I don't ever have to climb the stairs, I can take elevators. I mean, we've, we've, we've made our world so convenient and comfortable, um, and yet there are consequences to the... many of the things that we crave and want. So, in an ideal world, you don't wanna... You don't wanna rem-... I mean, you have to, uh, you have to honor and respect people's, um, um, desires, right? I'm not a... I don't believe in, in preventing people from taking the elevator, right? Or, or forcing them to, you know, eat, eat whole grain bread as opposed to white bread, right?

    4. SB

      But if you banned white bread and you banned elevators other than for those people that need it for accessibility reasons, et cetera-

    5. DL

      They would do better.

    6. SB

      ... over the long term, they'd be healthy and happier.

    7. DL

      They would, right. So the qu- it's really a balancing act between, between, um, um, respecting people's liberties and choices and educating them and helping them. So, in my world, I would, I would do more to nudge people, right? Um, I would... Instead of banning sugar, I would tax it more. Um, instead of, um, uh, pushing, uh, all kinds of foods on people, I would push... I mean, why don't we, why don't we advertise healthy foods the way we advertise unhealthy foods, right? I mean, when's the last time you saw an ad for just how amazingly healthy asparagus was, right?

    8. SB

      But that doesn't get the part of my brain going, does it?

    9. DL

      No, it doesn't. But, um, but we could do more to-

    10. SB

      (laughs)

    11. DL

      ... to nudge and encourage and help people, right? You don't have to, like ban sugar and cookies, right? Uh, the way some people... But, but simply promote, um, and help people help themselves, right? Most people wanna eat healthier food, most people want to exercise, um, but they live in a world where it's hard to do it, and they live in a world where there are very few incentives. I would make it such that healthy food would be as ex- as inexpensive as, as unhealthy food. And make sure that, that people had incentives and, and make it also fun to be physically active. Like, for example, um, every... I mean, who doesn't like to dance, right? Every culture in the world has dancing, right? Dancing is a form of, of physical activity. It's social, it's fun, it's engaging. Why don't we have... Uh, why doesn't every, every town in America sponsor dancing, right? Um, you know, it would probably do an enormous amount for people's physical health and their mental health. I mean, we could do that. I mean, that's just one example, right? So I would, I would, um, I would, I would, I would... And why is it that, uh, in medical schools, doctors don't learn about... They don't, they don't study nutrition and they don't, don't study exercise and they don't learn, um... 'Cause that's... Because in our medical system is designed to treat people after they get sick rather than prevent people from getting sick. So, so we need to-

    12. SB

      Yeah.

    13. DL

      ... you know, reverse how we fund healthcare, right? And so schools of public health are these kind of little marginalized places where, you know, where, where great ideas go to die, right?

    14. SB

      (laughs)

    15. DL

      And, and medical schools where all the money is, right? And doctors aren't taught to, to d- to, to... I mean, there are entire fields of medicine that don't have the word preventive associated with them. I mean, have you ever heard of preventive orthodontics or preventive, you know, optometry or preventa-... You know, the preventive orthopedics? I mean, it just doesn't exist, right? So we, we could do a lot more, um, and, and have enormous benefits.

  14. 42:18 – 48:25

    Should organisations force people to exercise?

    1. DL

    2. SB

      Chapter 11 of this book, you talk about someone who has taken their own approach to getting people moving and exercising, um, in their own business.

    3. DL

      (laughs) That's The Bjorn Borg Company. I love that.

    4. SB

      Bjorn Borg Company. Can you tell me about that, that company?

    5. DL

      Yeah. So I was, um...... so, uh, I was, I was curious about this idea of how to get, how to help people be more physically active, right? And again, you know, my, my fundamental hypothesis is that we evolved to be physically active either when it's necessary or rewarding. And so, I was curious if there was any, any companies in the world that have made physical activity necessary. In other words, what if we forced people to be physically active? And I found one. So far, I think there's only one company in the world that I know of, maybe there's some others, but this is the only one I've ever found so far. And it's the Björn Borg sports company in Sweden, where the CEO of the company is this crazy sort of exercise addict. And he, um, he requires every member of the company to, to exercise. They have sports hour every Friday at 11 o'clock. (laughs) So I actually, um, when I, when I was like searching around, and I was thinking, you know, w- working on the book, I actually, you know, I got... I, I thought, found a, an article about them, and I, you know, I clicked on the, on the company website. And you know how e- ev- most companies have a little Contact Us?

    6. SB

      Mm-hmm.

    7. DL

      So, I, I clicked on the Contact Us, and I wrote a little note saying, you know, "Dear Björn Borg Company, I'm a, I'm a researcher, an evolutionary biologist. I'm interested in exercise, and I'm, and I'm fascinated by how your company, um, requires people to exercise. Could I learn more?" And the next morning, there was a, an email from the CEO of the company saying, "Why don't you come and visit us?" So, so I hopped (laughs) on a plane, uh, few, few months later, went to Sweden, and they, they let me... He was so nice. He just let me just go anywhere in the company. And I, I went to sports hour, and I, I talked to, to employees, uh, throughout the company, and it was fascinating. I mean, um, a lot of the employees of the company, um... First of all, a bunch of people apparently left the company when he took over as CEO and r- required this. But it doesn't matter who you are. You could be working in the mail room. You could be the CEO. You could be a visiting board member. Whoever you are, if you're there on Friday, you have to go exercise with them. And they have this pretty serious kind of exercise thing. And apparently, some people quit. Um, but, um, but, but pretty much everybody else said, "You know? It's actually a pretty damn good thing." Uh-

    8. SB

      Do you agree with that approach?

    9. DL

      Well.

    10. SB

      (laughs)

    11. DL

      Yes and no. Um, every university in the world used to require, and every school, right, supposedly requires exercise, right? I'm sure you had-

    12. SB

      Mm-hmm.

    13. DL

      ... physical exercise, you know, phys, uh, some kind of phys ed required in your school. Those standards are slipping around the world, and more and more kids are doing less and less in school. Uh, universities w- are no exception. It used to be that all universities required some degree of physical education. Uh, mine was no exception. In fact, Harvard was a leader in that back in the, you know, a hundred and something years ago. And over the, uh, since basically the 1970s, that's basically disappeared. Although most students, if you ask them, they think, "Yeah, that's actually a pretty good idea." So, I don't know. Maybe we can bring back exercise as a, uh, and, and the thing is that if you get used to it, right, when you're young, you're more likely to do it when you're older, right? 'Cause you set... That's the age in which your habits become, become, well, your habits become your habits, right? And so, there's a certain age where, where if you can keep, keep, you know, s- get that, making it, make it a habit, you're probably more likely to continue doing it for the rest of your life.

    14. SB

      We kind of see it as overreach, don't we? I was thinking about if I was to announce at m- one of my companies that everyone is now required to exercise, it would seem like, like, uh, tremendous overreach. If I announced that everyone is required to read a certain book, they'd do it, and it'd be fine. And it might be seen as a positive thing, right? It might be a representation of our values that we are learners, and we're innovators, and we keep, you know, nourishing our brains. But if you turned around to your team and said, "Listen, we're all required to, you're all required to go for a run every day," or something, people would... It just feels personal.

    15. DL

      Yeah.

    16. SB

      Like, that's not the responsibility of an organization to tell me to go f- (laughs) exercise.

    17. DL

      But we have, we have company, you know, retreats. I mean, we do all kinds of stuff where people are required to do it. So I don't know. I challenge you. Try it.

    18. SB

      What we do and what we've always done, we even do it with this team, the Diary of a CEO team is about 30 people. So we have a fitness channel in the company, um, Slack channel, the communication channel that we use. And in that channel, um... And we did this at my previous company as well, where we would enable and facilitate. So we, we, someone started a women's football team, so we enabled it and promoted it. Someone started a men's football team, so we enabled it and promoted it. And this, this also applies to non-physical, sort of exercise-related clubs. Like, someone starts the read- reading club, and we enabled it and promoted it, um, and we also paid for it. If they need to, if they need new kits, for example, when the women's football team needed, wanted to have their own uniforms, we paid for it, because we saw a huge value in terms of staff retention, connection, community, and all those things that actually lead up to staff retention if we could have more social clubs outside of the office. You know, if you're thinking about leaving a job, there's a number of things you weigh up, the pay, the job, whatever. But you also weigh up how the community, like, the group of people I love and how much they bring to my life. And I actually think in the remote working world, um, it's something that CEOs and leaders have really not paid enough attention to, that if they really want to retain their team members, they should have them together as much as they can, even outside of the office, bonding. In a world where screens are on the rise and pubs are on the decline and social activities and churches are on the decline, there's less sort of, uh, institutions that connect us socially, work has a big opportunity to do, to do that. So one of my big things always in my head is like, "How can I get the team members of my companies to hang out more?" And, uh, and a multiplier to that is, "How can I get them to hang out more and move their bodies more? 'Cause then they'll feel better."

    19. DL

      Right. Well, well, think about it. It's play. Right?

    20. SB

      Play. Yeah, exactly.

    21. DL

      And, I mean, w- and play is what is another thing we evolved to do, right? When kids play, and we're one of the few species that plays as adults, right?

    22. SB

      Mm-hmm.

    23. DL

      And what is play? Play is a way in which you, you, you learn cooperation. You, you, you, you build community, um, but you also move your body,

  15. 48:25 – 50:03

    What did you learn from these tribes?

    1. DL

      right?

    2. SB

      In the first chapter of your book, you said that you went to visit the Native American tribe, and I'm gonna try and per- pronounce this, the Tarahuma.

    3. DL

      Tarahumara.

    4. SB

      And they're famous for their long running.

    5. DL

      Yes.

    6. SB

      What did you learn about running from them?

    7. DL

      Well, it's- you know, they have been famous for well over a hundred years. I mean, many, uh, people have gone to study the Tarahumara an- and have commented on their a- amazing ability to run. But what I, I really learned from them is that, um, uh, for them, physical activity is spiritual. Um, you know, there's this book, Born to Run, that, uh, that describes their, their running and calls them a hidden tribe of superath- super athletes. They're not hidden and they're not super athletes. Um, and, um, and the one thing that the book missed was that the m- the main impetus for the, for their, for their running, they do these famous long distance races, is that it's a form of prayer. Um, it's really very beautiful. Um, and, um, and it's a, it's a metaphor for, for life. And, um, and, and it's also a- an opportunity to bet in sports and all that. It's all wrapped into one. And, and what I've learned was that this actually used to be almost universal among Native American populations, right? Native American tribes. Everybody had long distance races and ball games and, and they were all had a spiritual element. It's just that they've, they've retained their traditions because they're in a very remote part of, of Mexico, uh, that's essentially inaccessible. We all used to do this. All, uh, humans used to do this. And in fact, if you think it- if you look around the world, every population has this tradition of endurance, endurance events.

  16. 50:03 – 56:38

    Why you should do strength training on your feet

    1. DL

    2. SB

      Some of the subject matter you talk about in your book, but also outside of your book, is, is how we used to run. Um, in terms of, you know, I was at the foot doctor. What's it called? I- I don't know what they're called. Orthro-

    3. DL

      Podiatrist.

    4. SB

      That's what I said. P- podiatrist.

    5. DL

      (laughs)

    6. SB

      What did I say? (laughs) But I went to the podiatrist the other day because I, I got this ... What's it called when you're f- I'm gonna point at it on my foot. This part of my foot here started to get lots of pain every time-

    7. DL

      Plantar fasciitis.

    8. SB

      That's it. Plantar fasciitis. I started to get some plantar fasciitis.

    9. DL

      Oh, so fun.

    10. SB

      And it was just this ongoing pain. And they prescribed me some insoles. I stood on a couple of machines, some soft stuff, and they measured my foot and took this scan of it and said, "Right, basically, you're standing wrong. Um, your arch is a bit too flat. Take these insoles and wear them in all of your shoes." And I just- I always think in these moments when someone prescribes me something that's not natural, I go, "Why?" Like, uh, where did I go wrong? And I think that's the key question. Where did I go wrong? Who lied to me? To the point now that at 30 years old, I have these bloody insoles that I have to put in all my shoes because f- presumably, that's not natural. Presumably my, my ancestors don't have bloody insoles.

    11. DL

      Yeah. So, plantar fasciitis is what I would call a mismatch disease, right? A disease that's more common or more severe because our bodies are inadequately adapted to modern environments. And in your case, and as, as is the case with a lot of people, you have a weak foot.

    12. SB

      (laughs)

    13. DL

      So, so we, you know, y- you look like you go to the gym.

    14. SB

      Yeah.

    15. DL

      Looks like you're a pretty fit person, right? I'll make a bet you, you strengthen pretty much every muscles group in your body except your feet, right?

    16. SB

      No comment.

    17. DL

      Right? (laughs)

    18. SB

      (laughs)

    19. DL

      Well, but we don't, right?

    20. SB

      (laughs)

    21. DL

      And one of the reasons is because we, we encase our feet in stiff-soled shoes that are very comfortable. And, and the reason the shoes are comfortable is that your, your foot muscles have to do less work when you're u- using those shoes, right? We have shoes that are stiff soles, they have arch supports, right? And your, your foot has four layers of muscles in them. And those muscles are supporting your arch. And at the bottom of those four layers of muscles is this layer of connective tissue, the plantar fascia. And the problem with the plantar fascia is that if it stretches too much, it, like anything else, right? It gets inflamed. But it's got almost no vascularization, right? So it ha- it's very hard for it to repair itself when it gets inflamed. To prevent plassar- plantar fasciitis, the best way to preventing it is having a strong foot. A strong foot's a healthy foot. So the way to, the way to treat the disease in the long term is to strengthen your foot. But if you wanna just alleviate the symptoms, that's what your podiatrist did. By giving you an insole, right? It's basically preventing your mus- your arch from collapsing as much, making it more comfortable so your, your plantar fascia gets stressed less, and so it can kind of, um, alleviates that, that, that, that, that stretching and hence the pain, right? So that's a typical example of what I call dis-evolution. It's what, what happens when you treat the symptoms of a mismatch disease rather than their causes or preventing their causes. So podiatrists are a bit like drug pushers in that sense-

    22. SB

      Ah, makes sense.

    23. DL

      ... right? Because they're, they're essentially putting your foot in a cast, right? And then, and for the rest of your life, you kinda have to keep using them, unless you strengthen your feet. So I, so, uh, so there's nothing wrong with those, you know, treating the symptoms. I mean, pain is no fun. So wear the insoles, right? To kind of, you know, alleviate the pain. But also work on strengthening your foot, and I think you'll find that the plantar fasciitis will, will disappear and never come back.

    24. SB

      So the plantar fasciitis, fasciitis, um, has now healed after about a month of wearing the insole. Um, I no longer have the insoles, um, with me here in, uh, uh, New York, and I don't have them in any of my shoes because I've also taken a bit of time off, um, running on my feet, I was playing a lot of football. So now I'm at a point where I can go to the preventable stage, prevent it happening again. And you said to strengthen my foot. How does one strengthen their foot?

    25. DL

      Good question. So there are some exercises, um, they're kind of foot doming exercises and things like ... which are, they're, you know, I can send you some links to videos showing you some good foot strengthening exercises. So that's one way to do it. Um, but the other way is to wear more minimal shoes. Um, to wear shoes that aren't stiff-soled, that don't have arch, arch supports. Go barefoot a lot, right? Um, and those, that will naturally strengthen the muscles in your foot 'cause you'll have to use those muscles. So you ever gone for like a long walk or run on a beach, right? And afterwards your, your feet are kind of tired?

    26. SB

      Mm-hmm.

    27. DL

      Right? The reason your feet are tired is because you're now walking on a compliant surface, right? It's not stiff.

    28. SB

      Mm-hmm.

    29. DL

      So your muscle's having to work more-... to stiffen your foot-

    30. SB

      Mm-hmm.

  17. 56:38 – 1:01:46

    Is too much muscle bad?

    1. DL

    2. SB

      When you, um, when you look at these tribes, are they... Do you know who Liver King is? Huge, massive muscles, talks about ance- ancestral living. Um, what do our hunter-gatherer ancestors look like in terms of their-

    3. DL

      Not like him. (laughs)

    4. SB

      No? Okay.

    5. DL

      I mean, look, think about it. Muscle is really expensive, right? It's actually a super expensive tissue. Uh, about a third of our body is muscle, and it's using up about, about a th- you know, a fifth or more of the calories that we're expending, right? Uh, just, just sitting there, not even using them, right? They're, they're very costly tissues, right? And so if you have more muscle than you need, you're basically adding to your, your cost of, of living, right? And if you're ve- and if you're a hunter-gatherer or even a subsistence farmer living on the margin of food security, having more muscle than you need is actually deleterious, right? Remember, the only thing that natural selection cares about is how many offspring you have who survive and reproduce. It doesn't care if you're strong or healthy or nice or loved or, you know, fun or whatever. It only cares about whether you have grandchildren. That's it, right? That's the s- cold calculus of selection, so to say.

    6. SB

      My brain is going, "If I have big muscles, I'll have more romantic opportunities-

    7. DL

      (laughs)

    8. SB

      ... and then I'll have grandchildren."

    9. DL

      Well, only up to a certain point, right? They don't... Y- so if more muscles, if, if they attract the opposite sex and, and ma- and make them wanna reproduce with you, yes, that could be a benefit. Um, um, I'm not so sure how much women are attracted to the Liver King, but, um...

    10. SB

      (laughs)

    11. DL

      Um, um, and that's not something I even wanna know the answer to, but, um... And certainly shouldn't ask him, but, um...

    12. SB

      (laughs)

    13. DL

      Um, um, but, but there's a reason we have "Use it or lose it," which you mentioned earlier, right? Because when we need, when we increase our demand, we increase our capacity, right? When you go to the gym and you work out, right, you build muscle, but if you stop using those muscles, you lose it. And that's an adaptation, right? Because you don't wanna spend extra energy on muscles you're not using, right? So you want enough, but not too much. You wanna be economical with muscle mass, right? Um, and so, uh, if you look at the data, um, from hunter-gatherers, and people have done that, they've done grip strength tests, et cetera, and all kinds of other fun things with it, like mini Olympics, and we, we've done this too. Um, people are reasonably strong, but they're not super strong, and they're not, they're not buff and built and bulked and all that sort of stuff. They've got enough muscle to do what they need to do, but no more.

    14. SB

      And the reason why people find muscle attractive anyway is because it's this evolutionary signal, isn't it, of, uh, reproductive value and, uh, resources, maybe, and the ability to go out and... Do you know what I mean? Why, why does, why does a woman, for example, find a man with muscles or in good shape attractive in 2023 when we're not hunting for gazelle?

    15. DL

      Well, I'm not a, I'm not a, (laughs) I'm not a psychologist or a, or... So I'm not sure if I, I'm qualified to answer that. But I could, I could venture to guess that obviously, if you're trying to, if... You know, we pair bond as a species-

    16. SB

      Mm-hmm.

    17. DL

      ... and we have been for, for millions of years, probably. You want to pair bond with somebody who's going to... And because we also have, have cooperation and food sharing, right?

    18. SB

      Mm-hmm.

    19. DL

      You wanna pair bond with somebody who's gonna be able to, you know, bring home the bacon, literally-

    20. SB

      Mm-hmm.

    21. DL

      ... and figuratively, right? But, but bringing home the bacon does not mean b- looking like Arnold Schwarzenegger-

    22. SB

      Yeah.

    23. DL

      ... at least back in the day. Arnold Schwarzenegger back in the day, right? Bing- being, bringing home the bacon back in the day meant being, uh, a persistent hunter, being able to run long distances and being moderately strong. So they looked more like a marathoner or, or a football player than they did a, uh-

    24. SB

      Interesting.

    25. DL

      ... a weightlifter, right?

    26. SB

      So it's conceivable, it's conceivable that someone who is really, really big is actually, um, less attractive, because they wouldn't have been able to hunt and run and hunt as well as someone who's a little bit...

    27. DL

      Yeah, and you also have to, you have to feed more, th- you have to feed them more too.

    28. SB

      Yeah.

    29. DL

      (laughs) And that's a, you know, those are precious calories. So I'm gonna guess that, uh... And look, if you look in, in, in non-Western populations, uh, you don't see physiques like that. This is a, this is a privilege of people who are able to go to gyms and, um, and, you know, eat, you know, you know, whey powder shakes and all that kind of stuff to kind of build their crazy muscle mass. But it's not something that our ancestors were able to do on a regular basis. That's for sure.

    30. SB

      A quick word on Huel. As you know, they're a sponsor of this podcast and I'm an investor in the company. One of the things I've never really explained is how I came to have a relationship with Huel. One day in the office many years ago, a guy walked past called Michael, and he was wearing a Huel T-shirt, and I was really compelled by the logo. I just thought from a, a design aesthetic point of view, it was really interesting. And I asked him what that word meant and why he was wearing that T-shirt, and he said, "It's this brand called Huel, and they make food that is nutritionally complete and very, very convenient and has the planet in mind." And he, the next day, dropped off a little bottle of Huel on my desk. And from that day onwards, I completely got it, because I'm someone that cares tremendously about having a n- nutritionally complete diet, but sometimes, because of the way my life is, that falls by the wayside. So if there was a really convenient, reliable, trustworthy way for me to be nutritionally complete in an affordable way, I was all ears, especially if it's a way that is conscious of the planet. Give it a chance. Give it a shot. Let me know what you think. (page turns)

  18. 1:01:46 – 1:06:58

    Running myths

    1. SB

      There's another myth that, uh, you bust, which I thought was really interesting, 'cause I think I know a lot of people that have used this as a, as a reason not to run. They say it's really bad for your knees.

    2. DL

      Oh, man. That gets me so mad, right? I mean, I hear this from doctors all the time, right? "Oh, yeah. Running is bad for your knees." Now, it is true that knee injuries are the most common running injuries. Um, um, but arthritis, which is really what they're usually talking about, um, it's absolutely definitively not true that running increases rates of knee, uh, cartilage damage in arthritis. So arthritis is caused by cartilage wearing away in a joint, right? And it's, it's a, it's a myth that, that c- running actually increases car- cartilage damage. If you have arthritis, running is excruciating and problematic. But if you don't have it, running actually, uh, if anything, may be slightly preventive, um, because cartilage joints, like everything else, benefits from being used, right? And so physical activity actually helps promote strong and healthy joints. We used to think that it just caused them to wear away, but actually, you know, like cars, you know, wearing away at their tires, but now we know that actually physical activity promotes, um, repair mechanisms in cartilage just as it does in other tissues in the body. And, um, um, and, and of course, the other thing about running is that I think a lot of people run incorrectly today. So, uh, so that's why we started studying barefoot running millions, you know, a long t- uh, a few, a bunch of, few decades ago is because if humans have been running for millions of years, most of that time, we were running barefoot. So we're kind of curious, how did people run before shoes? And what we learned was that today, shoes have these cushioned heels that enable you to essentially run the way you walk, right? You land on your heel. And everybody who's barefoot sometimes lands on their heel, but people who are barefoot often, more often than not, land on the ball of their foot and then they let their heel down. It's called a forefoot strike or a mid-foot strike. And when you do that, we worked out the biomechanics of that and published a paper on the cover of Nature, showing that when you do that, you actually prevent your foot from crashing into the ground, causing, uh, what's called an impact peak, a c- a collisional force. You run lightly and gently. So if you were to take your shoes off and run up Lexington Avenue here, I guarantee you, you would not be landing on your heels. Bef- within a few steps, you'd start landing on the ball of your foot because it hurts less. And so that's how we evolved to run. You, we evolved to run in a cush- in a, in a way that, that doesn't involve, you know, slamming into the ground with every step. And the, and that c- that causes less force around your knee. Um, the trade-off though, 'cause nothing comes for free, everything has trade-offs, is that it's harder on your ankles. Your calf muscles and your Achilles have to do now a lot more work to let your heel down. And so people who switch from heel striking to forefoot striking often have Achilles tendon problems. They get calf muscle problems. If they don't do it properly, they'll get... if their foot muscles aren't strong enough, they'll get all kinds of foot problems, right? So you can't just suddenly become a barefoot runner and start forefoot striking. If you're gonna switch, you have to switch gradually and slowly and build up strength and learn to do it properly. Another thing people do is they tend to run like a ballerina, high up on their toes. That's really hard on your ankles and your calves. So you got to do it properly, but if you... but it can have enormous benefits. And so, and we know, again, if you run that way, there's p- puts much less force on your knees. And again, knees are where people get injured the most. So I think a lot of knee injuries come from, um, um, from the way in which we run.

    3. SB

      So would you recommend, (laughs) if you can, to run more barefoot, especially if you have sh- those kind of shoes we just sh- discussed?

    4. DL

      Well, I think what matters is how you run, not what's on your feet, right?

    5. SB

      Okay.

    6. DL

      So I would say a barefoot style.

    7. SB

      How do I learn to run in a new way though?

    8. DL

      Well, I mean, there's some tricks.

    9. SB

      Right.

    10. DL

      So one of them is, um... first of all, I don't know how you run, so, so-

    11. SB

      Probably badly.

    12. DL

      ... so maybe, maybe you already run just fine. Um, but, um, a barefoot style tends to be, um, a high stride rate or high stride frequency, so, um, 90 strides per minute or 180 steps per minute, roughly. You know, um, s- 170 to 180 steps per minute is about right. Um, relatively short strides, so you're not throwing your leg out. And to me, the most important thing is not what we call overstriding. You ask any coach on the planet, they'll say overstriding is bad. Overstride is when you throw your leg out way in front of you when you land, and that leg is a stiff leg. So that, a stiff leg means more force, right? Um, and, uh, and, um, um, and it's harder on your knees. Um, and so if you... and so a good runner lands, uh, with their, with their shank, with their tibia vertical. So their ankle is below their knee. When you do that, pretty much everything will work out properly, right? Um, it, it'll mean that you won't land hard on your heel. It'll mean that your, your leg will be acting like an excellent spring. You won't produce a lot of breaking force. Um, it's a, it's a, it's, uh, to me, I think the most important skill in running is not to overstride. Um, and, um, so I actually tell... so, so don't worry about how you're gonna hit the ground.... just worry about your overstride. If you solve your overstride, you're more likely to run well.

  19. 1:06:58 – 1:09:21

    The best cardio workout

    1. DL

    2. SB

      What do you think some ... What's the best kind of, sort of cardiovascular exercise for the promotion of good health? W- uh, 'cause I've been doing some CrossFit stuff, I've been doing some HIT workouts. Um, I've been trying not to run, because I've had a few injuries, I'm trying not to run as much, 'cause it seems to be a little bit more impact than if I'm bullshitting myself there, but, um, so I've been doing some, like, HIT workouts ev- for 30 minutes a day when I leave here. And-

    3. DL

      Oh, you do HIT ev- you do HIT- HIT- HIT works every single day?

    4. SB

      Pretty much every day at the moment.

    5. DL

      (laughs)

    6. SB

      We track it with a f- group of friends we have. There's 10 of us in a WhatsApp group. Whoever's last, whoever does the least workouts every month-

    7. DL

      (laughs)

    8. SB

      ... is evicted. And there's a raffle, so there was a raffle yesterday on the first. Was it the first yesterday? Yeah. For a new member and we do that every month, and we've done it for f- three and a half years.

    9. DL

      That's great.

    10. SB

      I've been in there ... I was the first ever member, so I've been in there for three and a half years.

    11. DL

      Well, I think, you know, I mean, the most ... the best exercise is the one you like doing. You know?

    12. SB

      But is there one that's, like, better, you know, like, the-

    13. DL

      You know, I think you gotta mix it up. There is no one perfect exercise, right? I mean, I think what you do sounds, actually, pretty good, right? You got a mixture of, of, of, you know, low, slow intensity, h- y- some, some high intensity. You wanna have some strength training. You wanna have some cardio. I mean, we never evolved to do one thing, and our bodies are too complex to benefit from just one thing. Uh, mixing it up is, is the obvious way to go, right? Um, I think the bedrock for any kind of physical ac- I mean, you ask anybody, right? Cardio is the bedrock of, of, of, of, of, of exercise, right? It, it promotes the most health benefits, right? You know, it's good for your, good ... you know, you're burning energy, it's good for your cardiovascular system, it's good for controlling inflammation. But, but, but there are different kinds of cardio in high intensity versus low intensity, and there's also strength training, right? Uh, which is also, you know, important. So, you know, there's no ... Y- look, we've tried to medicalize exercise, right? It's like a-

    14. SB

      Yeah, we have.

    15. DL

      ... like there's a proper dose, right? You'll take this pill, th- this many milligrams this many times per week, right? Exercise, it doesn't work that way. There is no, there is no optimal dose. Everybody's different. It depends on are you more worried about heart disease, or Alzheimer's, or diabetes, or depression, or, you know, are you previously injured? Are you fit? Are you unfit? There is ... It's impossible to prescribe exercise in this kind of medicalized way. It doesn't work.

  20. 1:09:21 – 1:15:59

    The best exercise for weight loss

    1. DL

    2. SB

      A lot of people exercise because they believe it will help them to lose fat.

    3. DL

      Ah.

    4. SB

      Belly fat.

    5. DL

      One of the biggest debates on the planet.

    6. SB

      It, it has been a huge debate. Even on this podcast, I've had multiple people come and say a whole range of things about weight loss and cardio. And I'm, kind of, I don't know what to believe anymore.

    7. DL

      (laughs) Well, anybody who isn't confused doesn't understand what's going on, right? You know, it's, um, uh, it's sad that it's such a debate, um, but, um, but that's how science works, right? So, um, uh, as you know, I wrote about that in this book. Um, part of the f- explanation for the debate is that, again, what dose are you analyzing, in what population, uh, in what kind of context, right? So the ... Pretty much every major health organization in the world recommends that you get 150 minutes per week of physical activity. That's, kind of, like the benchmark. That's what the, you know, the WJ- WHO, the World Health Organization, considers the, the division between being sedentary versus active. So, and, uh, and a lot of people are unfit and overweight and struggling to be physically active, have struggled to get 150 minutes a week, right? So a lot of studies prescribe 150 minutes a week of exercise, walking, for example, or moderate intensity ex- physical activity, and then look at the effects on weight loss. And guess what? When you, when you walk a 150 minutes a week, which is, what, 20 minutes a day of walking, which is about a mile, a mile a day, you're not gonna lose much weight. You're basically burning about fif- 50 calories a day doing that, right? That's a piddling about of calories compared to drinking a glass of orange juice, right? So, so surprise, surprise, those kinds of studies show that those doses of physical activity are not very effective for weight loss. However, plenty of w- rigorous controlled studies that look at higher doses of physical activity, 300 minutes a week or more, find that they are effective at losing ... for helping people lose weight, but not fast and not large quantities. So you're never gonna lose a lot of weight really fast by exercising. It's just not gonna happen. Because, you know, a cheeseburger has what, you know, 800, 900 calories. You have to run, you know, 15 kilometers to lose that, to, to burn the same number of calories. And you're gonna be hungry afterwards, too, so you're gonna make some of that back. You have compensation. So, so physical activity is a w- is actually ... There's just no way around it. You have to be a flat earther not to argue this way. But there, you know, there, there ... Physical activity can help you lose weight, but it's not gonna help you lose a lot of weight fast, and not at the low doses that often are prescribed. But the one thing that we do agree on, and I think this is, would not be controversial, is that physical activity is really important for helping people prevent themselves from gaining weight, or after a diet, from regaining weight. And there are many, many studies which show this. One of my favorite was a study that was done in, in Boston on policemen.

    8. SB

      Mm-hmm.

    9. DL

      You know, policemen are, kind of have a reputation for, you know, having too many donuts and being overweight, right? And Boston is no exception. So they did this great study at, at, at the- Boston University, right across the str- acr- across the river, where they got a bunch of policemen on a diet, a really severe diet. The policemen all lost weight, but some of the policemen were, were had to diet and exercise, some just dieted alone. And as you might imagine, the ones who dieted plus exercised lost a little bit more weight, not a lot, just a little. But ... And then they tracked them for months afterwards, because most people after a diet, their weight comes just crashing back, right? The policemen who's kept exercising even after the diet was over and they went back to eating whatever the hell they wanted, donuts, whatever, they're the ones who kept the weight off.... but the ones who didn't exercise, whoosh, the weight came crashing back. Another good example would be the, uh, have you ever seen the TV show The Biggest Loser?

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