Even if you're more physically active, you're getting more exercise every day, or getting more physical activity every day, that doesn't necessarily mean that you're burning more calories every day than someone who's more sedentary than you. I think that we need to be honest with people. I think that that's the best public health message that's going to be accurate to the science. And I think the science says that exercise by itself is not a very good weight lustful.
Hi, my name is Rongan Chastier. Welcome to Feel Better Live More. Hello, how are you doing? Thank you for joining me on my podcast.
Today's guest is a researcher who I've been following for a number of years. In fact, he's a researcher who I referenced quite a bit in my last book, Feel Great Lose Weight, which was all about taking a sustainable and compassionate approach to health. You see, we've been told for many years that the more we move, the more calories we will burn. But this week's guest is here to explain why this way of thinking is simply not true.
Dr Herman Ponce is an evolutionary biologist who researches how our deep past shaped the way our bodies were today. And over the past 20 years, Herman has conducted groundbreaking research across a range of settings, including pioneering fieldwork where he lives with the Hadza hunter-gatherers in northern Tanzania. Now, the Hadza tribe are considered one of the last hunter-gatherer tribes in the world and really do provide a unique insight into the way that we used to live. In our conversation today, and in Herman's brand new book, Burn, The Misunderstood Sites of Metabolism, Herman reveals his findings that despite the fact that Hadza men and women get between five and ten times more physical activity every day than most men and women in the USA or Europe, their total energy expenditure, which basically means the amount of calories they burn each day is the same.
You see, his research is showing that we burn calories within a very narrow range, nearly 3,000 calories per day for men and 2,400 calories for women no matter our activity level. You see, on metabolism, the way our body burns energy affects every aspect of our biology from our pace of growth, reproduction, aging, all the way to our weight and our health, and if we burn more energy in one area, for example, we exercise more, our bodies will adjust by spending less energy in another. But this does not mean that we should not exercise far from it. Herman explains why movement really is essential for humans.
It's just not necessarily because of the reasons that we've already been told. This is a wide-ranging conversation about a whole host of different topics. We discussed what Herman learned about real paleo diets when he was living with the Hadza. We talked about how we've all been seduced by society and marketing into expecting every single meal to be mind-blowingly tasty.
And we also discussed Herman's key learnings from spending such a long time living with this wonderful tribe and observing firsthand this ancient way of life. This is an enthralling episode and I really hope you enjoy listening. And now, my conversation with Dr. Herman Ponson.
I thought we'd start by getting straight to the heart of one of the bits of research that you've done. And that is that moving more doesn't necessarily mean that we are going to burn off more. I wonder if you could expand upon that, please. Yeah, that's right.
So even if you're more physically active, getting more exercise every day or getting more physical activity every day, that doesn't necessarily mean that you're burning more calories every day than someone who's more sedentary than you. And it's surprising that that kind of goes against what we're taught and what we're told in both the nutrition classes, if you take them or whatever sort of basic biology you might have had or for that matter, every website that talks about exercise is a way to lose weight or every glossy magazine to sort of self-help idea about exercise and weight loss. And so it was a real surprise to us. And we came to this in a kind of a funny way.
We were doing work with really physically active communities in northern Tanzania and measuring energy expenditures. And even though they're more physically active than us, they don't burn any different energy expected per day is no different than you and me. Yeah, I mean, that's incredible to hear. I remember I think it was two or three years ago when I first came across one of your research papers.
And for me, it really helped me understand what I see a lot in clinical practice. I thought, oh, it's so good to see some research there because you're right. There is this narrative within the public health community, within the scientific community, but it's gone beyond that even within just common everyday conversation with people. It's an assumption that we all have made that moving more will lead to burning off more.
And that was what's so striking about those early research papers. I read it for yours, which is it's literally turning that on its heads. So what you're proposing is pretty game changing for a lot of people. Yeah, I think so.
I mean, it was game changing for us. I can tell you that it was a total sea change in the way that I think about metabolism and in the way that I think a lot of us on the sort of basic research side of things. I'm an evolutionary biologist, an anthropologist. I want to understand human evolution and how our deep past shapes the way our bodies work today.
So I didn't come into this from a clinical kind of public health training. That's not my background. So it's been fun sort of seeing that work be relevant and be in the discussion of public health. But we just want to understand how the body works, right, from a fundamental level.
And to discover that there's this really basic assumption that we're all making that had never really been tested very well. And then to go and test it, this relationship between activity and expenditure to go on, finally do that work and go, wait a second. This is not actually what we all assume coming in, what we're trained in coming in. That was really exciting.
So I think it is a game changer. I think you're right. Yeah. I think many people will have heard that and what does he mean that, you know, if I move more, you know, I know I can I can eat a Mars bar.
I can see the calorie content. And therefore you have it in gyms that are there for I can go and, you know, run for 45 minutes now or whatever the metric may be. So why don't you start at the, you know, right at the very beginning, you know, what is metabolism? How would you explain it to people?
What are calories? And then from there, can you then take that next step and show us why moving more doesn't always lead to burning off more? Yeah. Yeah, that's a great place to start.
So, so metabolism is just the sort of umbrella term for all the work that your cells do all day, right? So you've got 37 trillion cells and they all are doing work all day to sort of bring nutrients and break them down, make other other other molecules get waste out. You know, so this sort of housekeeping work that all of our cells are doing all day, all about work requires energy, right? And so you could measure all the products that your cells make and some people do that.
They study metabolomics is called the proteins and enzymes that your cells are making. So you can measure the output or you can do what a lot of us do, which is measure the energy expended for all that work. And it's basically two different ways of measuring the same process, which is all the work that those 37 trillion cells are doing. Now, you know, most of that work we're only dimly aware of or maybe even not aware of it all.
So it's things like your liver digesting your food and you know, doing all the work that your liver does. Your brain, your brain burns 300 kilocalories a day, right? We're dimly aware of that if we're aware of that at all. You know, your immune system, reproductive system, all these things that your body's doing all day.
Most of it that you're not even conscious of, that's metabolism. Now, the parts of it that we're aware of are the exercise parts, right? When we get moving, we get sweaty, we get our heart rate up, we're aware of that part. And so we tend to sort of equate energy expenditure per day with the activity part that we can see or we can feel.
But in fact, even for somebody who exercises regularly, then activity portion of your expenditure is only, it's well less than half of how many calories you're spending every day is spent on physical activity. Most of it spent on all the other stuff that you don't even know. Okay, so that's metabolism. And as somebody who's interested in human evolution and evolution generally, we want to know how all those calories are spent and where the activity parts cool, but we want to know about the energy spent on reproduction.
And on immune function and maintenance, all the tasks that the body's doing, that's why I get excited about metabolism, because you're sort of doing the forensic accounting of how the body is prioritizing the energy and energy out. So, as somebody who's interested in human evolution, you know, the genus homo, we're all homo sapiens, right? The genus homo has been hunting and gathering since its inception, since it evolves two and a half million years ago. And so homo sapiens, our species is just the latest sort of twig off this large bow of the primary family tree, which is our bow that the genus homo.
So to understand what humans are all about, and ecologically and evolutionarily, you need to understand what the body looks like and acts like it works like and metabolizes like hunting and gathering population that you need. That's that's the ecologically real sort of relevant lifestyle for us. But nobody had done it, right? So nobody had measured energy expenditures, total energy expenditures, and hunting and gathering population before.
And so in 2009 and 10, Brian Wood and David Reichlin, two of my good friends and collaborators, we went to work with one of the last hunting and gathering populations on the planet, which is this community called the their name as a HODSA. They're a community in Northern Tanzania. They get, they eat all their foods are all wild foods, you know, plants and berries and tubers and wild game and honey and they live in grasshouses in Northern, you know, in the Savannahs in Northern Tanzania. So they're a great intact, wonderful, gracious, lovely folks living in Northern Tanzania.
And, you know, so we went there and we measured energy expenditures and the reason we did it, the reason we did all the work to go and get the funding and take time out of our lives to go and live with these folks for a long time, a long process, was to finally understand how many calories they spend every day. So, you know, what humans spend every day when you're hunting and gathering. Okay, so HODSA men and women get about between five and 10 times more physical activity every day than men and women in the US or Europe, so they're incredibly physically active. If you're a step counter, right, the HODSA get about 13,000 to 19,000 steps a day.
Okay, right, plus they're digging up tubers and they're chopping into trees to get honey out of the, you know, because bees there put the builder hides in the trees and, you know, they're carrying babies on the back and it's a lot of work. We were sure going into we were certain that they would be spending tons more calories every day. Then we do in the West that was a whole that was the premise of the work right was going to go try to document that that deficit that we seem to have in the West. And instead what we found was that their total energy expenditures total calories that per day is the same indistinguishable from folks in the US and Europe and so, you know, to get back to this what is what is metabolism.
The answer is it's all those things it's the activity is the immune system it's, but what was happening is rather than just sort of adding them up in a kind of simple way. Obviously our bodies are able to kind of manage right and make the sort of economic decisions about how to spend those calories so that as someone who lives in a population like a HODSA actually don't have a top line number of calories per day that's any different than you and me, even though they're obviously spending those calories very differently lots on activity and less on other stuff. Yeah, I mean, you call this the constrained energy expansion model, I think. Yeah.
And we have this idea that how we utilize energy is additive, don't we? If I run for one hour, therefore, I have, you know, whatever, I don't even know how many calories that would in theory, you would burn off by doing that. But we sort of feel we can then go and eat an equivalent amount because we've just earned it, but it sort of works the other way as well, doesn't it in terms of if we have over eaten, we then think that, well, I can just go and I can go for a double run tomorrow or an extra long walk tomorrow to make up for it. But your research has shown that that just simply is not the case, at least for most of us.
No, that's right. That's right. That's the idea that you can run and earn your donuts, you know. And it's a dangerous way to think, actually, because when you don't understand how clever the body is about sort of manipulating the metabolism and you have a sort of simple view of how it works, then, yeah, then you can make sort of silly decisions like that.
Like a lot, you know, I can have the box of donuts because tomorrow I'm going to go on a longer run. And actually the body doesn't really work that way. The body is, it's a long term kind of time from the body's working under sort of a couple weeks or maybe a couple months, and it's paying attention to how physically active you are. And if you change that, if you start your exercise program and you're exercising more, you might lose a little bit of weight early on.
But as your body adjusts to that new level of activity, your total energy expenditure will sort of moderate and end up not a whole lot different than before you started. And now you think that you're earning all these donuts, right, because you've been really good and you're doing all your exercises. But in fact, those donuts are going to pile on because your exercise expenditure isn't doing what you think it does. It's not totally raising the total expenditure per day in the way that you think you would expect it to.
So how much does a typical Western man, a typical Western woman burn off each day compared to the population? Yeah, so the biggest predictor of how many calories you're going to burn every day is how big you are, right? Because I say we have 37 trillion cells, but obviously if we're bigger, we have more and for smaller, we have fewer. And so typical, you know, US or European or UK man burns about 3000 kilocalories a day.
And so it's about 11 megajoules if you prefer to do megajoules. And that has mostly to do with how big you are, how much you weigh, and particularly how much fat free mass you have fat fat burns some calories. It's actually it's an active tissue. It makes hormones and that kind of stuff, but not as much as nearly as active as all your other tissues.
So we kind of fat is relatively quiet. So it's mostly your fat free mass that determines how much you burn women in the US, UK, other parts of the industrialized world burn about 2400 kilocalories a day. And the difference is that in the amount of energy burned is because women are a bit smaller and tend to be a bit smaller. And also women tend to carry a bit more body fat.
So for a given, you know, if you're a man or woman step on the scale and they have the exact same total body weight, the woman probably will have actually a little bit less fat free mass because women tend to carry a bit more fat. And therefore, her expenditures will be expected to be a bit lower, not because men and women are fundamentally different physical and they are fundamentally different physiologically, but not because the expenditures are fundamentally different just because the body compositions and sizes are a bit different on average. And then a husband and women, they tend to be a short stature group of folks. And so, you know, they're a bit shorter than on average than the typical US or UK men or women.
So they actually burned fewer calories, women burned like 1800 calories a day, men are like 24 25. They're all shifted down because they're smaller bodied. But once you have, of course, we account for body size and competition whenever we do these analysis. Yeah.
I say one of the central points of your work to come through to people because I think it has, there's so many people who are struggling to lose weight. They are trying their torturing themselves, depriving themselves, punishing themselves all the time. And they're possibly doing it with the wrong equation in mind, right? So it's, it's, it's doubly tragic.
It's, it's, it's not working. And B, it's like, it's not working because actually you're putting in all this hard work and effort. And actually that's potentially not the right equation to be using. So we just sort of break it down again.
So we have, you know, let's say I'm a, you know, the typical Western man on average will burn off 3000 calories per day. Right. So 3000 calories is what they're going to use up. And you're saying a brain may use up 300 calories a day just to exist and do all the functions that we require off our brain.
Right. So there's 2,700 calories left on that sort of, on that very simple equation. So you're making the case, I think that our immune system, our reproductive system, breathing, lungs, liver spleen, basically all the organs in our body just to do their job. They are chipping away at that.
And so there's a huge amount of calories that are being burnt. Nothing's new with exercise just to be alive and engage with life on a daily basis. So then what happens? So for someone who then does go on a one hour run.
And that is all they think is going to be utilizing more calories. What happens in their body to keep that at 3000? You know, on one hand, you're taking from here, but you're sort of pulling back somewhere else. Is that the idea?
Yeah, that's right. That's right. A couple things to be clear about. First of all, day to day, you might still fluctuate in your expenditures.
Right. So if you always run 10 miles on Tuesdays and you sit on the couch all the other days, then yeah, on Tuesdays, you'll burn more calories. Because your body can adjust 24 hours. It doesn't adjust that quickly.
It's more sort of a lifestyle than your body gets used to a lifestyle. So if you're the kind of person that's running, you know, 20 miles a week versus the kind of person that's not the person who's running 20 miles a week. And your body's adjusted to that is spending, well, 20 miles. So it's about 200 calories a mile, right?
That's a good rule of thumb. So 20 times 100 to 2000 calories a week. So 2000 calories a week is being spent on exercise for you. And that means that person is spending 2000 calories less on all the other stuff.
And so that's what's exciting for me as an evolutionary biologist is figuring out what does the body prioritize, right? And so we know that some of the things that the body's reducing expenditures on, right, the things it's taking away from, are some of the really good things that exercise does for you. So if you look at that person who's running 20 miles a week, they're going to have lower inflammation levels. But what is inflammation inflammation is actually energetically costly immune function that your body doesn't need to do.
Right. It's your innate immune function, always on high alert when it doesn't need to be. And it's actually bad for you to have high background levels of inflammation. Stress.
If we look at people who are exercising versus those who don't, the people who exercise have a lower and shorter surge of things like epinephrine and cortisol in response to stress, right? And that's so there's spending fewer calories on that, on that stress response. And if you are over the course of day, you're constantly being on high alert because, right, that's not good for you either. So actually the suppression of that stress response is probably really good for you.
People who exercise a lot will have healthy, I want to stress this healthy, but lower testosterone estrogen and progesterone levels on average, a bit lower. That's going to help you save energy, too. So your body's basic. That's probably not the only thing that your body's doing.
You might be making other sort of subtle adjustments about how you, you know, do you sit rather than stand, that kind of thing. So your body's kind of making all these adjustments. And that's how that's, that's how you make the numbers work, that the people don't spend the 20-mileer a week and the sedentary person don't have different expenditures overall, because the 20-mileer a week is spending less on these other things. Yeah, I love it.
It just shows just how clever and highly tuned our body. So it's really humbling actually to think we, you know, we're smart on our bodies. Well, you know, we'll eat a bit more here, run a bit more. Wait, wait, we're far cleverer than that.
And I really, I love the fact that it seems or so we can prioritize different functions, depending on what's going on. So, you know, in, in, in burn, you write about, not just the answer, you write about another, another population. Because with tea, I don't know how you pronounce it. Yeah.
How'd you pronounce it? Chimani. The Chimani. Yeah.
And I found it fascinating that, that they 70% of them have an active parasite infection in their guts. Yeah. And therefore, I think you're saying that actually because there's that background level of infection and inflammation, that the body is potentially devoting more energy towards the immune system and the less to other parts of the body. Today's episode is sponsored by AG1, a daily health drink that has been in my own life for over seven years.
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For first time subscribers, see all details at drinkagone.com forward slash Live More. And they have a high pathogen burden too. As you can imagine, if you live without any sort of modern medicines, barefoot, mostly in really remote rainforest environments, you get a lot of parasites, you get a lot of bacteria, so your immune system is always active. And those kids, they have elevated basal metabolic rates just like we see with the chimani.
But what's cool is with the schwar population, we've got them, we've got children, so we can actually measure their growth while they're, because they're their kids, and Sam's able to show very nicely. If you look at the amount of immune activation, short term immune function, something we call we measure with CRPC or active protein, which is your body's first like flush of immune response to a really, you know, an acute stress. Kids who have that, they grow less in the subsequent couple of weeks. Kids who have these sort of long term, you know, markers, there's different immune function markers that we can use to say that's a long term infection.
That's a short term response. The long term responses are correlated nicely with kids long term growth. So the kids are constantly getting the most immune hit, right, are backing off of their, they're backing off their, their growth. And, and sure enough, when you measure expenditures, right, total energy expenditures, total energy expenditures are the same as kids in the US or Europe.
Right. So these kids are playing with, in other words, these kids are all playing with the same energy budget. You all get the same number of calories and you can spend it however you like, and if you spend it on immune function, you've got less to spend on growth. Right.
And sure enough, that's what we see. So that's prioritization is just super interesting to watch happen. Yeah, it's, it's truly fascinating. And, I mean, a little while ago, you mentioned that the HADSA tends to be shorter stature than, than I'd say, the typical Western population.
It's some of this playing in there as well, because of their lifestyle as you feel that maybe, you know, maybe we have, I don't know, you know, how would you sort of, yeah, how would you put that together? Well, yeah, absolutely. I mean, you know, we don't know, so height is a great example of a trait that has both a really strong genetic component, right, tall parents and have tall kids, and a really strong environmental component. Right.
So there's, and it's not nature or nurture or nature versus nurture, it's those things acting together. And so a population like a HADSA who tend to be short stature, they probably have a lot of gene variants that would, you know, even if they grew up here in the West, they probably would end up a bit shorter on average. So it's not just the environment, but I bet it's plain into it. And, you know, probably the best example of this is something called the immigrant effect, which was documented pretty well in the, you know, in the mid 1900s, which is that when you see, you know, people who grow up, the parents grow up in a developing country.
And without, you know, without access to great medicines and without maybe access to great food, and with maybe a lot of physical stress in their lives, their parents grow up and they're relatively short. They move to a country that has better medicine, better nutrition, less work stress for the kids. And the kids are all, you know, a few centimeters taller than the parents on average, the immigrant effect. And so that's been well documented in people from lots of different parts of the world.
You come from an energy stress environment, you move into an energy rich environment and your kids get taller, right, because your kids have less energy than you were as a kid on all these other tasks. I don't have a budget. I think it's brilliant. We've all got the same budget.
So it's just, where is your body going to allocate the resources? It's like, you know, if you have a certain amount of income, do you want to spend that on a small house and a fancy car, or do you want it on a, you know, you want it on a big house and a nice car or whatever, you know, it's a beautiful way of thinking about the body, I think. Yeah, that's exactly right. And we're talking about energy budgets all the time.
That's kind of how we think about it, right? And it's been fun too, because for some reason, in evolutionary biology, people got really comfortable talking about energy budgets in terms of like reproduction versus growth or maintenance, like immune function versus growth and talking about trade offs like that. And then somehow, even in evolutionary biology, activity was sort of this extra thing that could always get added on top and you could always just fund that somehow separately. And I don't know how that thinking never really took hold.
But basically, my work is saying, no, activity is just another activity. It's just another activity that your body has to do that is just part of the mix. It's just part of the budget, you know, and you kind of expand or contract the budget much as hard. You know, you might push a little bit.
You might get a little, but not as much as you think you're getting because your body wants to kind of maintain the same budget, no matter what. Yeah. I think it's important that we're super clear. You're saying that exercising more certainly in the long term does not lead to us burning off more calories, but you're not saying we shouldn't exercise.
In fact, you're saying quite the contrary that it's incredibly important. And I let this bit in the book, which I'm just going to read if you don't mind. Those ancient adaptations have consequences for us today. Our bodies are built to move in our modern industrialized worlds free of the daily demands of foraging for our foods.
We need to exercise for our bodies to function properly. It's a legacy of our hunter-gatherer past. Why is it so important that we move our bodies? Yeah, so this is another, I think, benefit of taking an evolutionary perspective.
And that is to understand that our bodies and our behaviors co-evolve. Okay, so really that's the example of this. It is in fish. You ever heard the example that people talk about sharks, if sharks don't keep swimming, right, they drown.
A shark can drown. Why? Well, because ancient fish, all ancestral fish, when they evolved gills, they evolved the ability to pump, they have muscles on their side of their gills that allow them to pump the water past their gills. So they can pump most fish and just hang out still and just slowly pump the water past their gills.
And they're fine, because they can keep on getting fresh water, oxygenated water through their gills. Sharks and tuna and a couple of other sort of really active species like that, really physically active species. They're swimming so much that evolution actually favored reducing and then eventually kind of eliminating, because why spend on energy if you don't need to, on that musculature, because they're moving all the time anyway, they can just kind of open their mouths and the water just kind of streams past their gills. And so now, now if you take that same fish and you don't let it move, it does, right?
So it's the behavior, the swimming all the time, and the anatomy, which is this color pumping mechanism, or a gill pumping mechanism, co-evolving. And that's a nice example that we can kind of all get a hold of, but it happens all over the place. This is how evolution always works is behaviors and anatomies co-evolve. In humans, right?
Again, we've been hunting and gathering for two and a half million years. And what does that do? Well, if you start hunting, and if you start gathering in Savannah landscape for the food is scarce, you need to walk and just move a lot more to get your food. You have to, right?
Food is farther apart to find animals will run free from you. You know, they want to get caught. And so hunting and gathering just requires a ton of physical activity. And so, you know, if you're born into the world with a body that expects to move, just like those, you know, a shark is born in the world with a, with a gills that expects to be pushed through the water.
And if we don't do that, if we rob ourselves of that constant activity that we normally get, yeah, bad things happen, right? Our physiology kind of expects that. And just like the shark that stops women, bad things happen when we stop exercising, because every aspect is actually hard to find out which challenge anybody to find a piece of your body that doesn't, that doesn't kind of isn't contingent on that activity signal for normal function. It kind of gets everywhere.
Yeah. And I guess that then speaks to how do we, you know, how do we talk about physical activity to the population? You know, how do I, as a medical doctor, talk about it with my patients? Because a lot of the time it's done around fat loss, weight loss.
And I think there's two sides of that going a little bit. I've seen a few of your Twitter debates over the last few months on this. And, you know, it's quite a controversial topic as to, first of all, is exercise needed for weight loss. And therefore, depending on what your view is on that, how do we then articulate that message.
So what sort of current, how many days in this for a few months and maybe several years, what is your current view on that? Yeah. I think that we need to be honest with people. I think that that's the best public health messages when it's going to be accurate to the science.
And I think the science says that exercise by itself is not a very good weight loss tool. And even exercise along with diet changes, exercise doesn't add a whole lot to the weight loss piece of it. It's not a long term, but because you're saying for a week or two or three weeks, you will get about it. You mean beyond that?
Yeah, long term. So, I mean, there's a great data on this that comes from all sorts of labs that aren't mine. So this isn't me speaking necessarily. If you look at the long term effects of exercise interventions, exercise alone, the long term expectation of weight loss is about two kilograms, right?
So that's great. If you're looking to lose two kilograms, that's perfect. But most people who are overweight or obese are looking to lose much more. And if you look at how much they're working, they sort of should lose much more, right?
The tons of calories are burning, but it doesn't work that way because the body adjusts. Okay, so I think sometimes my work gets sort of, I think, mischaracterized as saying that exercise isn't important. I think that's not what I've ever said. Exercise is super important.
Now, do we exercise for weight loss? I would say this. We don't exercise for weight loss, but you might exercise during weight loss for all the other benefits you get. But I think that if we want to move the number on the bathroom scale, and if we want to get fat loss to happen, then that has to be a diet approach, right?
And, you know, when you go to any, I'm not a clinician, so I would defer to people wearing clinical practice like yourself. But somebody comes in and has a serious weight problem, and we think that we look at their blood profiles, we look at their blood pressure, we look at the direction things are going and we say, look, this person needs to lose weight to get to a better place in terms of their health. There are a bunch of things you could prescribe, but wouldn't you make sure that you emphasize the thing that has the biggest effect, which should be that's diet, right? And so what I think is wrong, and that you see this in public health messaging all the time, is this equivalence of exercise and diet.
That's what bothers me, because that is not what the science says. So you say, well, you have that diet exercise. And so if we say it like that, it sounds like maybe I'll just do one or the other, and I could pick. Or it sounds like maybe exercise and diet have the same effect, because one's energy and one's energy out and I could just decide to focus on one or the other.
And that really isn't what the science says. The science says the diet is going to do all the heavy lifting and exercise to add on to that is fantastic and can do all kinds of good things, but it's the diet piece that's actually going to change the number on the scale. Yeah, I really appreciate your perspective on that. The last book I wrote was actually about sustainable responsible weight loss, and I quoted heavily your research in the exercise section.
And I think I said at one point, do you need to move more to lose weight? No, would I recommend it? Absolutely not. And I tell you why.
And I think this is, I guess, where my clinician lens comes in, more than a scientific lens, I guess, or maybe slightly more biased towards what I see with people, which is there's a lot of stress eating, there's a lot of comfort eating, there's a lot of eating when people are bored. You know, they know what they should ideally avoid eating too much often, what they should consume more of. Yet despite the knowledge, they're still doing it. What I found with exercise, particularly short bursts, like, you know, like 10 bicep curls every time you put a hot drink on in the kitchen.
What I found is that there's no quicker way to boost people's self esteem and their self worth than getting their body swing. So I find although it's not necessarily there to help them burn off more calories, which it isn't, I find, especially if I make it manageable for that person in the context of their life, like I find it helps them engage and stay on track with kind of all the other things I'd like them to do. That's wonderful to hear. That makes a lot of sense to me.
I would say too, just potentially, the advantage there is you haven't made exercise the reason that you're losing the weight, right? So if you dis if you dis if you disentangle those things, then you also disentangle the feeling of failure that I think is a real danger of exercise only weight loss approaches, which is if you're not losing weight, then you're doing the exercise wrong, or you're not trying hard enough, or somehow back on you that you didn't do the right thing. And I think that, you know, when we know that exercise alone is probably going to end up in pretty modest if any weight loss at all, and all of it's going to come early and you're probably not going to see much after that, then you're kind of setting somebody up for the realization in half a year or year later of this exercise program that, oh, this isn't really work anymore. And what is it?
Am I doing something wrong? Or is this even worse dealing, right? And so when exercise gets tied to weight loss like that, I think that's, I just service to everybody. Yeah, and that's incredibly damaging for people self esteem, because if they have diligently gone to the gym four times a week, pushed themselves, been on that treadmill for an hour four times a week.
And they're not seeing the results. They do feel like favors. And what does that lead to? More comfort eating, which actually compounds the problem.
And I think your research has so many implications for so many different aspects of health. You know, for me personally, one of the, one of the most funnest kind of conceptual points in the book was this idea that, you know, we've spoken about on the podcast before how chronic unresolved inflammation is at the root cause of, you know, many of these modern degenerative diseases, heart attacks, strokes, Alzheimer's, you know, rheumatoid arthritis, whatever it is. And I love this idea that because we have a fixed energy budget, if you were exercising more, then your body hasn't got as much budget left to give to inflammation. So it's actually going to drop down that kind of unnecessary chronic damaging inflammation.
I think, well, that's a very powerful reason to move our bodies more because we're going to reduce inflammation. So I want to thank you for that because that was a brilliant perspective that absolutely loved. Well, thanks. Yeah, I mean, when you stop thinking about exercise as just, you know, again, how many donuts have I earned, and you start thinking about all the things that it's doing internally to regulate that budget.
That's a lot more interesting, actually, right? Now you're thinking about, well, that's what exercise is doing to reproduction, what's it doing to immune function, what's it doing to stress reaction and you can begin to sort of follow the calories to the forensic accounting of it like I was saying. That's why it's so fun, you know, from just a pure biology point of view, but also, I think, powerful in terms of the clinical potential there. I guess just saying a weight loss for one for one more point.
And you did cover this in the book, actually, this idea that when we move our bodies, that can have indirect effects on weight loss in the sense that it can regulate our hunger signals and our hunger keys a lot better, right? Yeah, and so this is an interesting thing, too. A couple of sort of other, you're right, a couple of things added to the weight loss story. Exercise does seem to be really good for people to keep weight off.
So when people have managed to lose weight, usually by diet, exercise has been shown to be a nice helpful tool for keeping the weight off. And so I think it says, again, that kind of regulatory aspect is helping you either be solving your sort of self actualization about how much you eat or it's helping your mood or just helping your body, sort of the signaling in your body work better to match your intake at that new weight. There's also this piece of it where, and this is kind of not well understood because I don't think we focused on this enough. If you look at people who are really, really inactive, it's a great example of this is an old study in the 1950s done at a jute factory is the enormous jute factory, and you know thousands of workers.
And so there's sort of epidemiological studies to try to carefully look at activity and wait. And so what they did is they looked at people's jobs, of course, in the thousands of people, the factory, lots of different jobs, and some of them were clerks sort of pencil paper pushers, some of them were carrying bales of jute around something like had enormously physically demanding jobs like cutting the bales and, you know, so he had this whole spectrum of how hard your job was, and at the very, very low end, were the stall workers and these folks, as I understand their job was to just sit, just sit in the stall, you don't even you're not even walking on the floor, you know, taking boxes on your paper on your clipboard, you're just sitting. And then they looked at weight, a body weight, and really everybody's body was kind of the same from the pencil pushers, not the stall workers but the typical clerks up through the hardest working, you know, laborers. Everybody's weight's more or less the same except the people who really just were plug in a box and just sat all day.
They had weight problems, and they were overweight or obese depending on where they would fall in the classification. And that says to me that if you completely take the exercise signal away, completely, then you might have this dysregulation issue where you're, you know, that's going to lead to overeating. So in terms of exercise and weight loss. Yeah, the very, very low end of exercise at the zero end of activity, there seems to be a real regulation issue there that leads to overeating and who knows what else is going on in those folks lives but, but yeah, I think this is something again to sort of explore, not getting away from exercise as calories and getting towards exercise as regulation.
So I want to talk to you about your experience in Tanzania because, you know, I've read a lot of previous recent studies on the hats that they seem to be studied a lot. Yeah, that's true. There's a lot of microbiome studies on which I've written about before. There's a lot of, you know, what is their fiber intake compared to, you know, typical Western industrialized populations.
And I've always wanted to go and actually see that, to see what it's like and you've obviously done that several times. So, you know, paint a picture for us, you know, you grew up in America, you want to play in, you know, you know, what is it like? I mean, are you in an urban setting, then something that just sort of stops and has some atmosphere, you know, to walk us through that a little bit. Yeah, yeah, it is absolutely incredible.
So, you know, you go and you, you, you fly into Kilimanjaro airport, right, and you drive to a little city called Arusha, which is all in northern Tanzania and the landscape is very, you know, I grew up as a kid in Western Pennsylvania here in, you know, sort of green forested rolling hills. And I was always, you know, sort of taken by the nature shows and natural geographic that had the Savannah, you know, that kind of yellow grass, the case of flat topic, case of trees, elephants and zebra and the whole thing. So, you know, I think a lot of kids feel the same way, which just seems so amazing and cool. And so you land in Kilimanjaro and you drive out to Arusha and you're driving, you know, you begin to drive into this Savannah landscape and it's just like, wow, you know, you really feel like you've landed in someplace really different, at least from where I grew up.
And then, you know, Arusha is a little city, so you can get all your supplies, because everything that you're going to do with, you know, during your work with the house, it has to, it's a big camping trip, right, it has to all fit in the back of a land Rover. And it has to be camping food and you have to get water to bring with you because it's really dry out there and you have to get all your stuff, not to mention all your permits and everything. And so there's lots of regulations for, for doing the science and even just for going out there and so that's important too. So we get all of our paperwork and we get all of our, you know, supplies, and then you drive to another little town called Karatsu and it's smaller is half the size of Arusha and it's a half day away.
And then from there you kind of do your last pit stops and then you're out to a little town called Mangola right and so, and there are some hot camps around Mangola, if you want it if you want to go and visit the house sometimes that's where they go. And then you're, if you're doing, you know, work with the folks who are really hunting and gathering up remotely or even further past that more, you know, in the sort of space there's no villages or anything like that you're sort of driving through a case of trees on a little track or something like that. And you just roll up in a hot camp and so when I say you just roll up in a hot camp, you need to go with somebody who's been there, you can't just parachute in. And for us, you know, I've been there a few times now but I still, whenever I go with my colleague Brian Wood, who's probably spent more time in a hot camp than he's spent in his own bed in the past.
In the hot camp and in his own bed the last 20 years. And, you know, you sort of, yeah, you kind of show up and you know there's you can't call ahead. Right, there's no cell phone service somehow it's actually somehow the folks are getting cell phones now. Yeah, because they're trying to, Tanzania is trying very hard to put that part of the country on a cell network so it's pretty limited but some do have a cell phone that sometimes works, but you can sort of still can't call ahead because it's not even can't depend on it.
And, yeah, and so the camps are these, you know, maybe it's five, maybe it's 10 grass houses kind of around a nice flat area they always pick nice places. And permanent grass houses these kind of semi permanent structures. Yeah, I mean they don't so they're rooted to the ground that's a ground floor. The sticks are about you know is from, you know, kind of as big as your thumb to a bit bigger and they bring them up and bring them to the middle and if they snatch grass through them.
And, yeah, I don't know how they last a while and then I don't know what the type with the sort of shelf life is on a hard to house, maybe a year or something like this. I'm just trying to put myself in your shoes and just wanted what is that experience like for an American to rock up to this completely different tribe who's still living lives relatively untouched by modernity. You know, it's their fear and does that feeling get put at rest you know they skeptical one of these Westerners doing here trying to study us and our energy expenditure and our micro bias you know what I mean. Yeah, absolutely.
So remember kind of you know the door closing behind you and Land Rover, you know, when you're walking out and thinking what was going to happen. And what's funny is they, you know, the hots are just going to be more generous and more gracious and wonderful and they just kind of come up there smiling Hey, how's it going? You know what I mean they say from time on I got it. There's a greeting and Haza, which you learned very quickly because they make sure you know it, you know, everybody's super friendly and I'm sure it has a lot to do with showing up with Brian because they love Brian.
And it's not a big community it's only a few hundred people so Brian is probably met most of them and they all know Brian and they love them so you know if you show with Brian it's like showing up with, you know, with a pope or something I don't like showing up with a rock star. Anyway, yeah there's that moment of hesitation and then they're just so friendly and nice that you just kind of melts away and then you're just amazed. You know the guys are still walking around carrying bone arrow, you know, women have just shown up with with a digging stick you know that they were using just a 10 minutes before to dig tubers out of the ground. I mean it is it's very it's it's so different than anything that I'm used to and the environment's different now I grew up a lot in the woods so I like that part of it that's fine with me the sort of remoteness of it doesn't that doesn't affect me too much in terms of sort of being a shock because I've done a lot of sort of, you know, that country can't be in that kind of stuff.
But culturally it's just so so different, you know. Yeah, you know, one of the things that I've enjoyed the most about your book which I've got to say is one of the best science books I've read it's it's so engaging you know you've got science and it's you've got hard quality science and it's you've got stories in it you've got the evolutionary lens but it's these stories which, you know, they really they they lodge into my brain and they don't sort of they don't sort of leave them. You know, one of them was and I think I read this a few months ago when I got an early copy of the book from your publisher and I think you were there with Brian. I can't remember the chance name but I think he'd be an unwell with dysentery and some problems and an office you have a zebra so can you tell us a little bit about that story but also what can we learn from that because I thought it was really incredible.
Yeah, this seems like every day there's there's a moment like this if it's, you know, a cobra in camp or for somebody offers you one cook zebra you know anything can happen so that that story is fun so that was. Forget the year I think it was 2015 and we had gotten there to have the camp and it doesn't happen what first or second day that we got there the guys shot zebra and so you know you're in an intact ecosystem out there so that's that's a possibility that people might shoot a zebra and so they did. And you know zebra are big and so we've got brought back the camp, you know, you know, over people's shoulders and everything else and and then they slice it up into pieces lead all the organs pretty much immediately, and then the meat which is just a lot of meat on a zebra they slice into sort of thin strips and the hanger from the trees to let it dry. So the whole camp smells like a butcher shop for a couple days you know you know it was sort of three or four maybe more long probably more like a week in people were still eating zebra and we were going around.
One of the things we do is we hand out a little GPS units either where sometimes a clip on a belt, because we want to know how to use a landscape that that's one of Brian's big focuses is how they understand and use the landscape and that kind of traditional knowledge and trying to understand that because it's they just they know so much and I see it in such a different way that we do, but it's really just fascinating to see how they look at the landscape. How they use it so we give out GPS units where for the day, and that's that's fine and and we go and find this one guy I'm a nasi, and he had been just that ill you know he had like you know dysentery or something who knows if some kind of diarrheal disease acute infection for a couple of days. And they're like hey how's it going he feel okay he's like, you know, not really my stomach still is gross and you know last night was bad and any like any other hot guy has his little camp area he didn't have a family's by himself so he just has his little sort of cleared area of ground he put some acacia thorns around the sides and no animal walks up on him at night sits on the ground. He's got a little fire smoldering and he's kind of picking up pushing it around with his fingers and he pulls out a little chunk of zebra meat and realize he'd been cooking it kind of for breakfast.
And after talking you know he's like yeah man I've been so sick and just gross and he starts tearing pieces apart I think no he's gonna eat some breakfast and he just starts without even stopping this offers you know here's your zebra. And the zebra I didn't mind but having to hand it to you by a guy who just described you in some graphic detail about how bad is the eye tracks been you know and not a bottle of Purell in sight. And so you take it and you know I look at Brian and Brian looks at me like well you don't want to be rude so you pop in your mouth and it's like it's like I think if you if you pulled a piece of chewing gum off the bottom of a table in an elementary school you know and worked your way through that I think that's about the texture and the taste of it. But that's how the cuisine and that's what you can learn from it.
Well, first of all, yeah you learn how thankful we can all be for modern medicine and antibiotics and vaccines and all that kind of stuff because my god it's a hard life out there. Infectious diseases is you know is the number one killer you know little kids dial too often out there. It's really that's not funny at all it's a sad piece of it but even adults are sort of dealing with stuff you know day to day that we deal with a lot less because we have clean food and we have medicine. But the other piece of it is you know when people think about what paleo diets look like.
Yeah right paleo diet doesn't look like age grass finished you know Angus sticks that you've nicely seasoned and are pairing with your beautiful like asparagus no paleo diets are kind of most of us wouldn't want to eat a real paleo diet right a real hunter gatherer diet because it's it's pretty just you know it's just functional yeah really just it's just the energy and protein and and it's not like delicious. Yeah there's a couple of things in that story which really make me think the first is as you say what is a true hunter gatherer diet. And this idea that yeah they got the zebra so for a week that's what they're eating it's not like this idea well please correct me if I'm wrong here but this is something I really do feel is that we are seduced these days to thinking that every single meal we eat has to be phenomenally beautiful and tingle our taste buds and I feel that unintentionally social media and all these gorgeous cookery books actually make this problem worse because you see you know breakfast looking absolutely gorgeous but you don't realize that it actually took five hours to style that it's probably not even real it's probably dried it just and the lights have to make it look so great. And so you you kind of feel we sort of feel a lot that each meal has to be like that it's something you know even in my own family I'm very happy having the same thing for breakfast lunch and dinner if it's around whereas my wife will be hey babe we have that we have that for lunch we have that last time in that today.
It's really interesting because that's that is something I'm guessing is not what goes down in real hunter gatherer land it's like you don't really have that choice to you know whatever you can gather whatever you can hunt is what you eat right. Is that how we go? Absolutely. There's there are like breakfast foods and lunch foods and dinner foods in a hot camp.
It's just food you know and breakfast is whatever was left over from last night. I'm happy it's hot to get I think I ever saw the biggest smile on a face was it could walk in through camp with a skull of a dick dick a little antelope that his mom I think had given him and it was all boiled out except the eyeball. There's one boiled eyeball in there and he had his dad's knife which is like this huge. He's like why is your camp like prime eyeball out and you know he was so happy.
He was like you know smile everybody like me you know I got the eyeball and I think that was the treat that's your treat you know that's it isn't sort of the sugary breakfast snack and isn't the lollipop at the end you know it isn't the cookies. You know you get the eyeball good for you. And you know that's I think the seduction is exactly the right word that we have you know we've built these exotic diets for ourselves and a lot of them are full of really processed foods that we know push us to overeat. But even the well intentioned foods I think can do that because you know if your brain is evolved to eat a diet that's like the hods are eating.
And now you take that brain and you put it in a world where you get all the delicious food you want all the time. We shouldn't be surprised that our brains push us to overeat a little bit and over time that little bit adds up as a lot of obesity. And of course it's very hard to overeat these kind of real unprocessed foods right your your brain sort of will tell you when when you're following did you see overeating of any sort that you could that you could tell did you observe different sort of bodies. And you might see.
Yeah. I've never so we've seen a couple of I think, you know, one of the things we do when we go to a hot table is we measure ways types and weights that's kind of a baseline data point that we get everybody in camp. And so I've measured heights and weights for. I think probably a thousand hods at this point has a men and women and kids and and I can remember seeing two women over the course of my 10 10 years of working there on and off that would be classified I think is overweight or maybe class one obese.
So two and a thousand. And you know that who knows what their stories were necessarily. They do occasionally like spend some time in the village and then come back so I don't know how that obesity or over witnessed developed. I can tell you I've never seen how the women or men sort of doing what I would consider to be overeating.
You know what looks to my eyes to be overeating. I'll say this they're not you know they're not like scrawny you know they're they're healthy vital folks it isn't like they're starving and they're always always more food if they want to go get it. They never have the look or this they never talk about being you know starving for food. I mean they're often if you're if they come by your camp so we set up our research camp kind of outside of theirs to kind of stay out of their hair as much as we can.
And if they swing through and we're eating something then we always share yeah to share so they're always happy to have a bite of whatever and you know so they're they'll always eat. But they're not starving they're you know they're healthy weight and but yeah it's really rare to see any other way. What sort of food did you have your own food or would you consume hats of food because what's really fascinating is when they do rock by your camp and you offer them something what are you offering them and does it tingle their taste was in a way that it's like hey you know that's pretty cool I want a bit more of that. Yeah that's a good question.
They we offer whatever we have and so we always bring we have to bring your own food and so unless you've grown up in that environment. You will die if you just try to eat whatever's there you know I can't hunt as Zebra I'm not going to do that so you can't eat there so I mean if you show up in your another group of at least four each time because there's me and Brian and a couple of research assistance we all have been in school and and and want to help out as research assistance we hire HADA community members to help us with the research which is really fun. And so you know there's four of us at least in our camp and we can't impose on them and say you know feed us. They could do it actually but it would be hard you know we just don't do that so we it's like a camping trip for us we bring all of our food in you know in cans or packets or whatever.
Which means that when they come by you know it's it's maybe it's spaghetti and meat sauce or something like that or be rice and beans and I mean it's camping food it isn't like it's. Not necessarily but they leave whatever and they're always like yeah thanks nice check it later I mean it doesn't blow their mind I wouldn't say but they like it. Yeah yeah it's fascinating the the other thing I learned from that or I took from that story about the Zebra is that he shared it with you. Yeah and you've said that a couple times in this conversation you always share.
Yeah and so you know go beyond the central thesis I think there's a lot we can learn about human nature from your work and I'm interested you know with so much division in the world so much fighting but the message I get whenever I read about Hans Gather is whenever I you know through reading your work that there is a sort of equality and there's kind of there's that sharing is part of who they are and I guess does that make you think that's kind of who we are as well but we've sort of lost it somewhere. Absolutely you know in the discussion about ancestral diets and paleo diets and all this stuff. There's all this focus on the hunting or the gathering right is are we supposed to eat all animals we're supposed to eat all plants and what gets completely lost is that it's not hunting or gathering is hunting and gathering right. Well the and part means you're sharing because the and part means that some of us are going to hunt some of us are going to gather or we're going to agree to come back at the end of the day and share.
And we're the only primate that shares like this and we've been doing it for two and a half million years as long as we've been hunting and gathering. So the and it's the reason that we're so phenomenally successful as a species right because when we share we make more energy available for everybody because nobody goes hungry. We widen the portfolio broad and the portfolio of foods we can eat. So and we also knit our communities together more tightly because we have to depend on this sharing.
And you know the fact that look now that we're sort of slowly emerging from all the covid lockdown stuff what's the first thing that people want to do right. They you know they want to go to a pub and they want to share some chips and their beer right and they want to have a barbecue and they want to have people over and share. I don't know how wide all this is right away but this is what people are getting to do right this is what people have missed is to get together and share food this is what humans do. We're built to do this.
And the danger of course is that we're built to share within our group. Right we don't share indiscriminately across groups we share within our group. And so what people have manipulated and politicians are very good at this is deciding who is not your group. And you say those people are those people are not our group and they're the ones who are causing trouble.
We're going to be a family. We're a family who are really in the US is talking about the real Americans. Well who the hell is everybody up for all Americans right if you're here in the US. But it gets talked about the kind of divisive ways and you take this beautiful thing that's really phenomenally important and unique about our species and kind of beautiful this sharing and community that we don't have another species.
And you weaponize it because you say you know that's only within our group and not across and then we decide who the other groups are and you can weaponize that really effectively. That's that's the sad piece of it. How was spending time with that had to change to you individually yes there's the science game changing science which I think will have major implications all over the world. But on a personal level you know you go back to America with all this experience having witnessed something that many of us only read about and imagine that you've been there in society.
But you've been there and seen it. You know is there anything that you put into your life on the back of that. Yeah I think seeing how it's it's it's the similarities and the common humanity across these cultures that I think is really really the most powerful thing to bring home. You go there and we talked about how you know you get out of the land Rover it's so exactly different.
But the reason I love to go there now is the fact that when I see how the kids running around camp I see my own kids right when I see. How's a couple talking about what they're going to do that day or bickering or laughing I see my friends you know talking about my couple's friends talking about their families and what they're going to do. And I see that same commonality that same humanity throughout all of it. And I think to see the same shape of a life.
But in such different terms. You kind of gives you an outside view that you see the whole thing in a kind of an outsider's view and then you think oh wait what if I did that to myself what if I could look at my own life. And I can decide what I liked about it when I wanted to change. You know and I really it gives you some perspective.
You know do you really want to work seven days a week or do you want to make sure that you have time for your family you know do you want to get three hours of sleep every night or do you want to sleep better and exercise more and be healthier in your old age. Do you want to you know what's important and what's important for the haza are for those personal connections that they nurture throughout life because that's who they're with in that social mix every day. There's no you know Billy's going to go for the brass ring and check out and work you know work himself to death. No people do that like why would you.
And so I think that that perspective has been helping for me to kind of slow down calm down nurture the personal connections that's been useful for me. Yeah I love that such profound wisdom and what you said that something I think we can all learn from. Just as we draw this conversation to a close one thing I really wanted to briefly touch on relating to your work on energy. And we're really scratching the surface here that the book has got so much stuff in it that I think frankly anyone would enjoy reading it really is that that compelling a read from start to finish.
But there was a spit there where two things relating to that which is doesn't matter how far you walk or run or how fast you do it you're going to burn up the same amount of calories if you run one mile in let's say 15 minutes or you run it in eight minutes. You're still going to burn off the same amount of calories which I found if I've got that right I found that fascinating and the other thing was when you compared the different movements and how walking we revolt to walk it's so efficient to walk we hardly burn off anything. Running as well but you said swimming and how costly that can be so I just wanted you to sort of touch on those points just to finish off. Yeah so this is this is funny because my earliest graduate student work was on the biomechanics of locomotion so you know the walking running climbing we still do some work like that in my lab.
And it's just a really fun game to kind of reverse engineer the body and think about yourself as as a machine moving through space. And like any machine we might be interested in how many calories how much energy it burns to go a mile and you're actually absolutely right so so running. The mechanics of running you're like a pogo stick you're bouncing along and the just the mechanics of that mean that you're going to end up running about 100 calories a mile depends on how much you wait because if you're heavier that each side of the pogo stick is is more more weight more energy but so most of us about 100 calories a mile walking when you walk you do this amazing thing which is that you turn your body into a roller coaster track. And so you're going up the hills and down the hills and up the hills and down the hills right so in a roller coaster right because you got that first big kill.
And then it lets you go and then you use the energy from the top of that first sale you use the energy to go all the way through the whole thing into the end right and that you need to use the same trick when you walk so as you walk. You kind of don't notice it but as you your heel hits the ground and you kind of vault up over your leg and that's the top of the hill and then you see the middle you know any step you're doing this roller coaster thing and it's so remarkably efficient. That you burn about it's really only like half the calories of running it's incredible how much energy you say and we're the only animal that walks with that particular kind of a gate there are other two legged animals of course but we're really we're we're special in how remarkably efficient we are. And so that's really fun but you still move up and down right which is why I'm sitting here drinking my coffee sitting down so I don't have a top but if you go to your local you know t shop or coffee shop and you walk out the door you gotta put the lid on first.
You don't even know right but you're on his roller coaster the whole time. Yeah. And then swimming well swimming we're not evolved to be very good swimmers and so there's no special bit there. You're just in but instead of you know just sort of pushing yourself off of solid ground now you're dragging yourself through the water.
Well that's that's hard and so you know I don't know off top of how the numbers compare but it's a lot more calories to swim a mile than it is to walk or run it. I'm climbing as well is that right climbing was more than running a walking as well. Yeah so that's really fun so climbing we just published a paper on this oh sorry we just had it's impressed it's not even out yet. It doesn't matter if you're built like a monkey because people have measured this monkeys or if you're built like us or anything to climb to get your body to climb let's say 10 meters up a tree.
It's the same amount of energy per kilogram of body weight no matter how you're built. So you're if you're if you've had a mechanic you're at the high school students listening to this will be familiar with this which is that if you want to calculate how much work was done how much potential energy was gained when you go from the ground up to the top of the tree. It really is like a textbook physics problem which is kind of fun. You take the mass of the thing which is your body weight you multiply by gravity and you multiply it by the vertical number of meters climbed and that's how much potential energy in jewels that you climbed.
And it turns out that all muscle is kind of equally efficient at doing that work. And so kind of doesn't matter how you're built and how you do it. It's the same calories to go up the top of that tree again whether you're built like me or whether you're built like a monkey or whether you're built like. Yeah for sure are there so much interesting stuff that you talk about right about and we barely scratched the surface and I really appreciate you making time to come on a podcast today I've really enjoyed speaking to you.
The podcast is called feel better live more when we feel better in ourselves. We get more out of life and I wonder if you have on that theme any sort of closing notes closing thoughts perhaps your research really is profound it's game changing you know have you got any sort of final words of wisdom you can put it all together so people can start to improve the quality of their lives. That's a hard question because I think it's so personalized right what you need to do for you is going to be unique to your own situation but here's what I would suggest start by getting outside I think it's hard to go wrong. Get outside if you get outside what are you doing you're away from your refrigerator for one thing you're probably moving that's another good thing.
If you're getting outside with friends that's even better right fresh air vitamin D is hard to go wrong people in the industrialized world spend about 90% of their life inside either inside a house or inside a car, and we aren't evolved to do that. You know we talk about the details of a diet or details of exercise program but a good place to start is just get outside more. Evan thanks for joining on the show and I hope we get a chance to do it again at some point in the future. Thanks so much for the conversation it was really fun.
Really hope you enjoyed that conversation as always please do have a think about one thing or one idea that you can take away from this conversation and start applying into your own life. And of course do check out Herman's brand new book burn the misunderstood sites and metabolism it is a really really good read. Before we finish I want to let you know about Friday five it's my weekly newsletter that contains five short doses of positivity to get you ready for the weekends. I usually include a practical tip for your health sometimes I write about a book that I've been reading or an article or video that I found inspiring sometimes I share a recipe that I'm making or a quote that has caused me to stop and reflect basically anything that I feel would be helpful to share.
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Making life's not changes always worth it because when you feel better you live more.