Why Walking Is The Superpower You Didn’t Know You Had with Professor Shane O’Mara | FBLM Podcast

Dr. Rangan Chatterjee 0:00 [upbeat music]

Dr. Rangan Chatterjee 0:04 So Shane, welcome to the Feel Better, Live More podcast.

Shane O’Mara 0:07 Uh, thank you. I'm delighted to be here.

Dr. Rangan Chatterjee 0:10 Now, Shane, ever since a friend of mine sent me The Guardian article about your book, I have been really looking forward to trying to get ahold of you and actually locking you down for a podcast. And I'm really intrigued as why does a neuroscientist feel that it's important to write an entire book on the subject of walking.

Shane O’Mara 0:29 So, uh, walking is this astonishing capacity that all humans have. Uh, it's kind of like the superpower that we have that we've overlooked. And, uh, the science o- of walking has come together in a really beautiful way over the past 10 or 15 years. And, uh, when my agent said to me I should write a book on walking, I felt like I'd been slapped in the face because, of course, I should have written a book on walking. I knew the literature, and, uh, uh, it's something I'm passionate about, and I wanted to tell the story of it.

Dr. Rangan Chatterjee 0:54 Yeah.

Shane O’Mara 0:54 It's that simple.

Dr. Rangan Chatterjee 0:55 Amazing. I guess a lot of the best books are the ones with the simplest ideas, right?

Shane O’Mara 1:01 Yeah.

Dr. Rangan Chatterjee 1:01 And they often come from a passion as well. And so you're hinting there that you've always loved to walk. Is walking something you've always done? If you look back in your life, can you, can you think back to, you know, as an adolescent, as a kid? Has there always been something about walking that's appealed to you?

Shane O’Mara 1:18 Uh, funny enough, yes, and, uh, but the realization I should write about it [laughs] never did. So it's funny that when something is that close to you that-

Dr. Rangan Chatterjee 1:27 Yeah

Shane O’Mara 1:27 ... sometimes it takes somebody else to, to, to point it out to you. I remember, you know, when I was very young, we lived in the countryside, and I used to love, uh, tramping across the fields and disappearing for hours at a time and scaring my poor mother and then eventually returning.

Dr. Rangan Chatterjee 1:43 Yeah.

Shane O’Mara 1:43 Um, so even then, I, I used to love walking.

Dr. Rangan Chatterjee 1:46 And this morning, before you got here today, we're, we're recording this around lunchtime. It's just gone 12:00. Have you been walking this morning? Is this something you do to prepare for interviews or anything like that?

Shane O’Mara 1:55 I- I've done about 7,000 steps this morning, uh-

Dr. Rangan Chatterjee 1:58 Wow

Shane O’Mara 1:58 ... already. And, uh, on a day that I'm happy with my walking, I typically have done 15,000 to 17,000, uh, steps, and I don't think that's extraordinary. I think this is something we should all be doing.

Dr. Rangan Chatterjee 2:09 Wow. I mean, that's incredible because I think a lot of people listening to this will be familiar with the, the adage about walking 10,000 steps a day. And I've, I've written about this before saying I'm not entirely sure that there's, you know, brilliant research saying that it should be 10,000 steps a day, but I think for many, it's a pretty good barometer. Um, so w- I think we should go into that in terms of, you know, are human beings walking enough in the 21st century? I guess we're recording this in London, so I'm particularly talking about us urbanites who I guess are always trying to become and get more physical activity into our lives.

Dr. Rangan Chatterjee 2:48 Are we walking enough?

Shane O’Mara 2:50 Yeah. So I don't think we are. I think evolution has constructed us to walk lots from very early in life, from, you know, 16 or 17 months of age, uh, all the way through to really late in life, so 80s, 90s. And we can do that very, very well for long distances, long periods of time. But we've built an environment that acts against us. So w- humans have two major things we must do. We must source energy. Uh, so and we've solved that problem in the modern world. We can get food very, very easily from all sorts of places. But the other side of that, the, the exercise, the movement that we've engaged in to get food, we don't need to do anymore. Uh, so we've designed a world, like look at the world we're sitting in here-

Dr. Rangan Chatterjee 3:28 Yeah

Shane O’Mara 3:28 ... uh, where w- we should be upstanding, mooching about, and we don't do that. Um, now the 10,000 steps is, is a really... I think is a good guideline. It's not well-founded in terms of good bodies of data, but it, it's worth thinking about what we know about what people actually do. So, uh, we know from smartphone data that the, uh, country that walks the most on average per day is the Japanese. They w- typically walk about 5,000 steps a day each. Uh, the country that walks the least is Saudi Arabia. They walk around about 3,000 steps a day. The UK is, and the US are in there at about 4,000 steps a day on average. Um, we're capable of very, very much more. So a child or an infant learning to, uh, to walk, uh, does enormous amounts of walking. Uh, when you actually measure what they do, the average kid walks about 2,003 steps, 2,300 steps per hour and falls on average back on their butt about 17 times per hour.

Dr. Rangan Chatterjee 4:23 Wow.

Shane O’Mara 4:23 Um, so kids are made for this. We adults are made for it. But we've engineered a society that, uh, uh, militates against it.

Dr. Rangan Chatterjee 4:32 Yeah. I mean, I guess that's, that's very similar to the problems we've got with our foods, um, you know, our food supply, our food environments. We very much, you know, as humans, we, you know, we've always had to go out and find our food. You know, it's always been pretty scarce, and so we've got to use activity to go and get that food. What food was available to us would be dictated by geography and climate. Whereas now we're living in a world where actually the food environment is pretty similar, like 12 months a year, whether it's summer or it's winter. Uh, we have readily available hyper and, uh, ultra-processed foods which are having a consequent impact on our health, not just obesity. So I guess there's a very similar theme, isn't there? The environment in which we are living is working against us.

Shane O’Mara 5:18 Yeah. And I, I think you see the, the problem is the default is easy. We can blame the individual. Uh, and it's, it's very easy not to see the system around you. So where does your food come from? How is it sourced? How is it treated? But actually, we treat this as a, as a, as a, a problem of, of calories and money. We don't, we don't treat it in, in a much greater and wider sense. And, and movement is the same issue. In my own building, for example, I always use this example. To get to the stairs, I have to go through three fire doors, whereas to use the lift, the lift is just in front of me.

Dr. Rangan Chatterjee 5:49 Yeah.

Shane O’Mara 5:49 So the default that we provide ourselves is one of ease, uh, when actually we can engineer things so that we get a bit more movement in. And if we can do that during the course of the day every day, it'll be, pay us, uh, benefits in all sorts of ways that we aren't conscious of, but we will be glad of.

Dr. Rangan Chatterjee 6:05 Yeah. You know, on the way here, I got the Tube from Euston to Pimlico. And when I was coming out at Pimlico, uh, Underground Station, there were two sets of stairs on both sides, and there was ... Sorry, there was two escalators on both sides, and in the middle was a set of stairs. And I was coming out, so I was having to go up. And I have made it a rule, where possible, to never outsource my physical activity to a device or a machine or to an electronic, uh, appliance wherever I can. I'm not perfect, but I did think ... As I was going there, I thought, "Okay, you know what? It is quite far, but I'm gonna take the stairs." What was interesting is that I observed myself on the stairs, I observed who was around me, and at the top I had a look back, and I was the only person certainly in the time that I was there who took the stairs. Now, I'm not saying that in terms of putting blame on anybody else who was not doing it. I appreciate many people struggle to walk up that much. Maybe the air's not fantastic in the Underground. People are tired, they're carrying bags. I totally get that, but I guess that is very much reflective of what you're saying, isn't it? It's, it's easier for us to take those escalators than it is for us to take the stairs.

Shane O’Mara 7:12 Yeah. Uh, and the defaults are the easy things 'cause y- 'cause humans, you know, we are lazy. And, and, and I don't mean that in a pejorative sense. We, we h- are, are designed to conserve the energy that we've, uh, harvested, uh, because, you know, we're waiting for the lean times that will come, and we've engineered our world so that those lean times don't happen anymore. Um, but, you know, y- the problem of designing the environment is a, is a difficult one. Like, should there ... Instead of stairs, should you have ramps, uh, for example? Uh, should these be actually, uh, placed, uh, in a kind of a parallel fashion rather than a, a, a straight vertical fashion? Will people use them more if, if, uh, th- there were other designs available? If, if, uh, there were lifts present, I guarantee you people would use the lifts. Um-

Dr. Rangan Chatterjee 7:56 Yeah

Shane O’Mara 7:56 ... so th- this is ... Like, and, and this is the tendency that we cannot blame people for-

Dr. Rangan Chatterjee 8:00 Right

Shane O’Mara 8:00 ... because we've all inherited it. And it, you know, asking the individual to do something about it is not the place to look. What, w- what we have to do is to look at the issue of how the environment itself is designed. Is it one that facilitates movement? And generally, no is the, the sad answer. You know, the pedestrians are thought of as the ... Uh, we're the last path or the last-

Dr. Rangan Chatterjee 8:20 Yeah

Shane O’Mara 8:20 ... piece in, in the design chain, but actually we should have our design centered around what we need to do.

Dr. Rangan Chatterjee 8:25 Yeah. It, it's almost seen as impolite as well, isn't it, to, to point someone towards the stairs. And what I mean by that is if you check into a hotel, for example, um, you know, as you get your card or your key, they will say, um, "You know, and so, you know, it's just over here. Just walk down here and the lift is there. Lift is, you know, first door on your left," something like that. Uh, nobody really tells you, but also the stairs are just a bit further down through that dark door in that sort of murky passageway.

Shane O’Mara 8:50 [laughs]

Dr. Rangan Chatterjee 8:51 You know, it's everything's set up, and, and I, I kind of understand that. You know, I think people are trying to be polite. They think, "Hey, you know, someone's checked into my hotel. Let me point them to the easiest way that it is for them to get up to the third floor." Um, but we're seeing around us, aren't we, the consequences of this. And I guess one of the things that really struck me when I was reading your book, which I've got to say is fantastic, and I would highly recommend people read it-

Shane O’Mara 9:13 Thank you

Dr. Rangan Chatterjee 9:13 ... really. If you're wondering if you should be walking more, um, or why you should be walking more, I think that book will certainly convince you. But there was an interesting point where you talked about how many times, and you've touched on it already in this conversation, a child tries and falls on their bum when they're trying to walk. And for me, I'm thinking why, on an evolutionary level, a child is pretty stable, aren't they, on, on their all fours. They can crawl around. They're, they're not gonna fall and do themselves any damage.

Dr. Rangan Chatterjee 9:43 Why do we as human beings put so much effort into getting off our fours and getting up onto two feet?

Shane O’Mara 9:51 Yeah. So th- this is kind of like the great, uh, one of the great questions is to try and understand how this evolved. So, uh, primates generally, uh, adopt a kind of inter- an intermediate form of walking. So they're, they're not pure quadrupeds. They don't walk around on four limbs. Uh, chimps, if they want to go quickly somewhere, they engage in what's called knuckle walking. They lean forward, and they power themselves with their limbs, but they also push their knuckles into the ground. Um, the consequence of the, the way that we interact, uh, or the ... Sorry. The way we move is that the range that we can in- uh, extend over is much greater calorie for calorie than a, a chimpanzee, our nearest living relative, can do. Uh, and our, in terms of the calorific demands of walking, our form of walking is extremely efficient. It's about as efficient as it's, uh, as it's possible to be. So our food ranging, our food finding, food foraging capability is much greater simply because we can walk. Um, and because we can walk, we can use weapons. Uh, we can carry weapons. We can kill things. We can dismember them, and we can do something which no other species can do. We can jointly carry, uh, the prey that we have killed together on a spear and bring it back and cook it. Um, so walking allows us ... So the fact that we've evolved this kind of slightly odd posture brings with it all sorts of advantages that are denied other species, and it's an ecological niche that other species don't occupy, you know? So other, other animals that are bipedal, like birds, do not occupy the same ecological niche as we do. Their head is in a very different position to ours, and they don't have, uh, hands that they can move and, uh, interact with the world with.

Dr. Rangan Chatterjee 11:28 So in many ways, are you saying that our ability to walk is what fundamentally makes us human?

Shane O’Mara 11:36 Yeah. And, and not alone that, but our ability to walk is what allowed us to conquer the planet, uh, because we are able to walk, let's say, 18, 20 miles a day every day from early in life until late in life. So if you think of that long walk out of Africa we did 120,000 years ago, um, it doesn't take long to cover a couple of thousand miles if you don't have a fixed place of shelter. All you need to do is just walk to the next safe place. Uh, and we can do that, and we can do it in small migratory groups, and have done it in small groups. And we know this because of the, the trace fossils- Of human migration that exists in Africa and, uh, in other places. Uh, humans are very, very good at being attuned to others when they're walking. We sense when somebody else senses danger when we haven't. Uh, if, if people turn their heads to something suddenly, we reflexively turn our head in the same direction, even though we haven't detected anything. We're taking our cue from the other person. Um, we can carry infants, and we can also do something which to my... I, I haven't been able to find any other species that can do it. We can carry food and swallow while walking-

Dr. Rangan Chatterjee 12:44 Yeah

Shane O’Mara 12:44 ... um, because of the peculiar position of our gullet relative to our stomach. Birds, for example, you'll see them, they might walk a little while they're swallowing a fish, but they have to throw their heads back, uh, in order to let the food drop directly into the gullet. But we can walk and talk, hence people walking with burgers and- [laughs]

Dr. Rangan Chatterjee 13:02 Yeah

Shane O’Mara 13:02 ... chips and all the rest of it.

Dr. Rangan Chatterjee 13:03 It, it is incredible, Shane, to think about this, that there are all these kind of, um, adaptations, these evolutionary adaptations that we've undergone to facilitate these things. You know, why, so why should we be able to walk and eat at the same time or, um, you know, walk and carry our prey back, or walk our way out of Africa to, to basically go across the whole world in a way that I don't think many other species have done, right?

Shane O’Mara 13:30 No. The, the mosquito probably, and the rat. But, uh-

Dr. Rangan Chatterjee 13:32 [laughs]

Shane O’Mara 13:33 ... they followed us. Uh, and horses and, and cattle followed us as well. Um, so they're, they're tracking our, uh, humans, or they're coming along with humans because we've bred them for our own purposes. Uh, but it, it just so happens that when you, you go back and look at the, the, the, the various, uh, kind of evolutions of, or, or evolutionary pathways of primates as they evolved in Africa, some are more upright than others. Um, and that will have given them at that time certain advantages that, uh, it would've been denied others. So f- range is, is a very, very clear one. We can walk very long distances, particularly in the noonday sun when, uh, predators like, uh, tigers are lying down asleep. Um, and we cast a small shadow, and we can sweat. Uh, and we can carry our own water, you know?

Dr. Rangan Chatterjee 14:22 Yeah.

Shane O’Mara 14:22 So we can, we can do a lot of things that other species can't.

Dr. Rangan Chatterjee 14:25 Yeah, absolutely.

Dr. Rangan Chatterjee 14:27 A lot of people make a similar case about running. They say our ability to run is fundamentally what makes us human, and actually allows us to, uh, do a lot of things that our predators can't do, and al- allows us to, you know, track, um, our prey for long periods of time. And I guess, you know, have you thought about it in terms of running as well, and is there a fundamental difference between-

Shane O’Mara 14:48 Yeah. So-

Dr. Rangan Chatterjee 14:48 ... walking and running or are, are they almost like-

Shane O’Mara 14:50 I, I-

Dr. Rangan Chatterjee 14:50 ... sort of brothers and sisters together?

Shane O’Mara 14:52 Yeah. I, I, I, I don't buy the, the story on running, uh, uh, as, as, as much as some people might push it because children don't run to hunt prey. Um, th- they, uh, will only start to do that when they, they get into their teenage years when they're strong enough to do it. Now, humans have one remarkable ability where running is concerned, and it's called persistence hunting. Uh, we can run, uh, uh, herbivores to ground, uh, because we can sweat to cool. They can't. They have to stop and gulp air in order to cool down. S- uh, but we're not fast runners. We're not like antelopes. We're not like gazelles. We're not like tigers or cheetahs. Uh, so we, uh, can wa- run at moderate speeds for reasonable periods of time, but we can walk at high speeds for very, very long periods of time. Um, and I don't think we should think of the two as being, uh, kind of contraposed to each other. You, you will have in any group of humans some who are exceptionally good at running, uh, and they'll be the persistence hunters. You'll have others that will follow them-

Dr. Rangan Chatterjee 15:52 Mm

Shane O’Mara 15:52 ... um, and they'll be the, uh, persistence walkers. [laughs]

Dr. Rangan Chatterjee 15:55 Yeah. No, that's a good way of looking at it, and I'm, I'm mindful that we're, we're recording this literally 24 hours after Eliud Kipchoge broke the-

Shane O’Mara 16:02 Broke the two hour

Dr. Rangan Chatterjee 16:03 ... two hour-

Shane O’Mara 16:03 Yeah

Dr. Rangan Chatterjee 16:04 ... record for-

Shane O’Mara 16:05 My gosh. Yeah

Dr. Rangan Chatterjee 16:05 ... well, not, not the record, I guess. He's the first human to have run a marathon in under two hours, from what we can tell certainly. Um, which is incredible. I, I saw a film, uh, recently called 3100. I actually interviewed the, um, the, the, the director of the film recently and, you know, he, he filmed a variety of different running experiences around the world. One of them was, uh, a tribe in the, um, the Kalahari Desert. And he talks about, um... Well, he doesn't talk about it. He shows us that these guys, running is a way of life for them. But, uh, but I think what you're trying to say, I think, is that actually not all of us have to be runners, and I guess all of us can be walkers.

Shane O’Mara 16:49 Yeah.

Dr. Rangan Chatterjee 16:49 I think that's the key, isn't it? All of us have the ability to walk.

Shane O’Mara 16:52 Ability to walk. Yeah. Um, but remember as well, uh, your ability to run in certain environments is really restricted. You can't run in a forest very easily. It's dangerous. Um, your risk of injury rises, uh, as your speed rises, uh, especially if the forest is very dense. Uh, it's very difficult to run on a rocky, uh, in rocky terrain. You're better off walking rather than running because, uh, a- again, of the, the, the risk posed by, by, uh, uh, the terrain you're on. Um, muddy riverbanks, things like this, again, you have to be very, very careful i, i- in terms of, of, uh, your strategy for getting around. Um, and the data are very clear on this. People who run a lot run the risk of injury. Um, and the, the rate of injury rises, uh, per million steps run. It does not rise per million steps walked. It's approximately flat.

Dr. Rangan Chatterjee 17:43 Wow. Well, that's incredible, especially when many of us are, I guess, we're trying to be more physically active, and many people join the gym or they, they join a new exercise class and within a couple of weeks they get injured and then they can no longer engage in the activity that they wanted to do, and that leads them to being sedentary.

Shane O’Mara 18:02 Yeah.

Dr. Rangan Chatterjee 18:02 So you're making the case, I guess, that walking is probably one of the lowest risks It's one of the lowest risk but also highest benefit activities that exist

Shane O’Mara 18:14 Yes. And I'm also making the case that our society doesn't facilitate it [laughs] .

Dr. Rangan Chatterjee 18:18 Yeah.

Shane O’Mara 18:18 And that's the problem that we have to counter. Um, uh, you know, uh, on the walk to here today, for example, I had to... Or we had to stop multiple times, uh, uh, to allow cars to go past. There are... You know, you don't get those long, easy stretches of walking in, in a city that, uh, we could and should because, uh, engineers typically have worried about engineering car flow and regulating pedestrians for the benefit of cars rather than the, the other way around. And cars have only been with us 100 years, but we've been walking-

Dr. Rangan Chatterjee 18:49 Yeah

Shane O’Mara 18:49 ... for tens of millennia.

Dr. Rangan Chatterjee 18:51 Yeah,

Dr. Rangan Chatterjee 18:51 so it's madness, isn't it, that we've, we've revolved everything around the motor vehicle?

Shane O’Mara 18:54 Yeah.

Dr. Rangan Chatterjee 18:54 I, I think it's worse in America. I've just come back from, uh, 10 days in California, and it's incredible. I was staying with a friend in Santa Monica, and, you know, these guys take Ubers everywhere. And I, I had a meeting to go to, and I looked at Google Maps, and I thought, "That's only one and a half miles away. I think I'm gonna walk." You know, I don't need to take an Uber for that. It's, it's a nice day, as, as often is the case in California. What was interesting is I had a little look in my, in my head. I tried to figure out roughly which way I needed to go. I, I try my best not to use Google Maps too much when I'm walking if I can help it. Obviously, sometimes I need to. And in America with this, with the kind of block system, it's often a lot easier to kind of facilitate in your head y- and, and understand where you are going. And I started walking, and then I, I knew I was on the right track, but then I came up to, like, an intersection that I simply couldn't cross, and I had to almost back up a few streets and go around it. And I've noticed that in a few American cities that it is literally set up around the motor vehicle. And if you're trying to walk places, you know, you cannot walk every single route. There are only specific ways, and you can get around. And yes, America's got a huge obesity problem. Yes, there are many, many different factors, um, when it comes to obesity a- a- and, you know, chronic lifestyle-related illness. But I can't help but thinking something culturally in America is, is, is causing a big problem. It's, it's set up around the motor vehicle, and it's not set up, it's not set up around the human being who wants to walk on their two feet.

Shane O’Mara 20:29 Yeah, and you see this when you, y- again, you look at the, the kind of what are the walkable cities, and you look at the indices of, of what are walkable or what, what makes a city walkable. So i- if you look at cities like New York, uh, Boston, and San Francisco, people walk a hell of a lot in those cities. They're, they're very densely packed cities with lots happening in the cities, and there isn't a lot of room, relatively speaking, for cars. There are cars there, obviously. Go to places like Atlanta. Outside of the city center, there are no footpaths. You cannot walk. Um, you know, and, uh, the, i- in, uh, California, y- you look at the contrast between, uh, somewhere like San Jose and, uh, San Francisco, very similar climate. Um, one is very car-bound. The other is limited in the number of cars because the bay is in the way, um, and they've got a very good public... Well, a reasonably good public transport system.

Dr. Rangan Chatterjee 21:20 Mm.

Shane O’Mara 21:21 Um, so y- you can see even within the cities that are in the US, some are much more walkable than others. And interestingly, the more walkable cities are the ones that are more expensive, and people like living in them more. Uh, they don't have the same experience of anomie and other things that, uh, people in car-bound cities, uh, have. Uh, so the US has a, a particularly, uh, major problem in, in allowing people to walk. And again, if you look at the, the index of walkability, um, cities in which people, uh, have to drive a lot tend to be fatter cities, um, that people-

Dr. Rangan Chatterjee 21:54 Yeah

Shane O’Mara 21:54 ... tend to have a, a problem. But it's unsurprising. Uh, you, you have to get into your car to go to the shops, to go to work, to do anything.

Dr. Rangan Chatterjee 22:01 Yeah. You've got a lovely mnemonic in your book that you hope that, uh, town planners and city planners start adopting. I wonder if you could share what that is. And then also share since the book has been out, has anyone been in contact with you, um, i- in, you know, with interest of sort of using your expertise to help them redesign their city centers or their town centers?

Shane O’Mara 22:24 So, um, well, I finish up, uh, the book, uh, on the theme of social walking, and I, I think this is kind of one of the things that's been very much overlooked when you look at the evolutionary literature on how we walk. Uh, our walking is social. We're really good at synchronizing our behavior together. We're... When we're walking, uh, we start to walk at the same pace naturally. We look upon it as, as something aggressive when we're with somebody who persistently walks ahead of you, um, at too high a speed. Um, and what I argue for in, in, in that chapter is we must have a, a charter for mobility that's based around the needs of humans, around pedestrians in, in our towns and cities. And that needs to be baked into the public policy process at the start. Um, and to do that, what I've, I suggest is we have a, a very simple way of, of, of, uh, remembering this, and the word I use is ease. Um, so our cities should be easy, uh, should be easy for everybody to get around and easy to walk in. Uh, they should be accessible to everybody. And I mean that for not just walkers but also for people who are mobility impaired, who've got problems with vision. You know, we need to design our footpaths so that they've got the little bubbles for people to step on so that they know they're, they're at the, the edge of the footpath. Uh, we, we need to, to lower the edges of footpaths so that people in wheelchairs can get around much more easily. Um, uh, our cities and towns should be safe for all walkers, and the walkers should take primacy, uh, where, uh, walking... Or sorry, where movement is concerned.

Dr. Rangan Chatterjee 23:52 Yeah.

Shane O’Mara 23:52 We shouldn't mix cars. Uh, we, we should, uh, really try and just engineer cars out of things. Uh, and then our cities and towns should be enjoyable, so, which is the, the last letter of ease, and it should be enjoyable for all. And the implication there is that we should stop thinking of, of streets as thoroughfares. Uh, we should be thinking of our streets as destinations Places that people want to hang out-

Dr. Rangan Chatterjee 24:16 Mm-hmm

Shane O’Mara 24:16 ... uh, places that people can enjoy. Um, and the reality is, you know, if you wanna be strictly utilitarian about it, streets that are thoroughfares are not economically active streets. Streets that are destinations are really economically rich because people hang around and spend their money there, they meet their friends there. Uh, they become almost like outdoor shared living spaces or living rooms-

Dr. Rangan Chatterjee 24:40 Yeah

Shane O’Mara 24:40 ... that, uh, we can all, uh, be in together.

Dr. Rangan Chatterjee 24:43 And I, I think that economic point is super interesting because unfortunately a lot of the things that needs to happen in society to make change are when there's an economic driver there. You know, the moral driver, the health driver often doesn't appear to be enough, which is incredibly frustrating, but you're sort of saying that there is an economic case as well-

Shane O’Mara 25:00 Yeah

Dr. Rangan Chatterjee 25:00 ... when we, when we do this. And I guess there are so many examples these days, even the town in which I grew up, uh, and which I now live in, um, I remember as a kid, the main, the main kind of shopping high street, you know, cars would go down it and people would park on it. And, you know, maybe, might even be 20 years ago now, it became pedestrianized, and there was a huge, you know, kickoff at the time. People were unhappy with it, but everyone's accepted it. Everyone's happy. It's a really nice, vibrant place to sort of walk around now because there are no cars there.

Shane O’Mara 25:32 Yeah.

Dr. Rangan Chatterjee 25:32 So people feel safe. The kids can run. They're, they're not constantly having their parents telling them, "Stop, stop. Don't do this, don't do that," because they can run freely and walk freely. And is this a pattern that we see that there is-

Shane O’Mara 25:43 We see this everywhere you go.

Dr. Rangan Chatterjee 25:44 Really? Resistance at first-

Shane O’Mara 25:45 Resistance at first

Dr. Rangan Chatterjee 25:45 ... and then acceptance.

Shane O’Mara 25:46 So, so Galway, where I'm from on the west coast of Ireland, uh, it... the, the main street is a street ironically enough known as or called Shop Street.

Dr. Rangan Chatterjee 25:53 Okay. [laughs]

Shane O’Mara 25:54 [laughs] Um, because when it was an old medieval town, this was the first street-

Dr. Rangan Chatterjee 25:58 Yeah

Shane O’Mara 25:58 ... that, uh, shops were built on, and the resistance there to pedestrianization was astonishing. But actually now it's this amazing street that runs from the center of the city all the way down to the, to the river, and, uh, it's a really vibrant cultural quarter, and nobody would go back. Um, and if you look in London, for example, uh, where we're doing the rec- the recording here, when you look at something like TripAdvisor or one of these things to, to find out what tourists rate as the best attractions in London, it's Covent Garden. There are no cars in Covent Garden.

Dr. Rangan Chatterjee 26:29 Yeah.

Shane O’Mara 26:29 It's Buckingham Palace. There are no cars outside Buckingham Palace.

Dr. Rangan Chatterjee 26:33 Yeah.

Shane O’Mara 26:33 Um, uh, it's the, the, the galleries. It's all of these places that humans can assemble freely together. It's not the gyratory at the Elephant and Castle. Uh, it's certainly not the A40 West. Um-

Dr. Rangan Chatterjee 26:44 Yeah

Shane O’Mara 26:44 ... you know, people might drive in that and think, "Whoa, I'm glad I don't live here." But people do not come to London in order to enjoy the, uh, the, the motorway system.

Dr. Rangan Chatterjee 26:53 Yeah.

Shane O’Mara 26:53 They come to places that other humans can congregate. And this, you know, again, another theme that comes out of the book is that we underestimate how important sociability and social life is to humans. Um, and the creation of kind of social spaces that we can freely walk around in, uh, is one of the, you know, when architecture does it well, it's one of the great achievements and that makes a city an attractive place to be, like the old Italian cities, for example.

Dr. Rangan Chatterjee 27:20 Yeah.

Shane O’Mara 27:20 Bologna, wonderful place to, to walk around. Uh, Florence, if you, if you look at Piazza della Repubblica or those kinds of places-

Dr. Rangan Chatterjee 27:28 Yeah

Shane O’Mara 27:28 ... wonderful places for social living.

Dr. Rangan Chatterjee 27:31 Yeah. And I think back now to European cities I visited on, on holiday, and there is something, you know, particularly these Italian little town centers, they're so... It's so, you know, there's not much room for cars.

Shane O’Mara 27:42 That's the joy-

Dr. Rangan Chatterjee 27:42 There's not much room, right?

Shane O’Mara 27:43 Yes, that's the joy of those cities, um, that there is no room for cars. And, uh, what you have is a kind of a stable and wonderful lifestyle that has been there for hundreds of years, long before the car evolved-

Dr. Rangan Chatterjee 27:54 Yeah

Shane O’Mara 27:55 ... and will be there long after we've decided that actually car-bound living is a mistake.

Dr. Rangan Chatterjee 28:00 Yeah.

Shane O’Mara 28:00 And Italians love their cars, you know?

Dr. Rangan Chatterjee 28:02 Yeah, absolutely.

Shane O’Mara 28:03 But they haven't tried to squeeze them into, uh, these little old towns, and they're lovely for the- for their absence.

Dr. Rangan Chatterjee 28:09 You mentioned social walking, and I find that incredibly interesting, this idea that as we're walking, people around you probably start to synchronize their cadence and their speed and, and, you know, and many other things that allow us to walk in large groups. And I'm... But I think about, you know, there's a lot of protests going on at the moment about, you know, climate and all kinds of things, and often it's done with peaceful marches. So is there something about a group of humans walking together in a march that is... I mean, what is that doing? Is something going on with our brains? Why do we feel that walking together is a great way of actually demonstrating it and expressing the strength of feeling that we have, uh, for a particular issue?

Shane O’Mara 28:51 Yeah. So this is something else that sets us apart from all other, other species. Other species herd, uh, but they do it, you know, for reasons of protection, uh, or they do it for reasons of migration. We do it for something which is in our minds, uh, which is, you know, to protest against legal structures. You know, they're not something you can touch in the world or political structures. You can't touch them, but, but they're, it, it's a ki- uh, something that w- we all share together. Um, and, uh, humans, uh, when, uh, uh, we gather, many of us, not all of us, but many of us f- uh, have this feeling of effervescence as it's referred to, uh, which is the kind of the joy of the merging of yourself with others who are bound together in, in, uh, a similar kind of, of mission. And, uh, the, the, again, as I said, it's a, uh, an absolutely uniquely human, uh, propensity. The problem is, though, uh, kind of twofold. On the one hand, uh, autocratic states don't want people gathering together in shows of, of force... or, sorry, shows of, uh, showing their dissent against the, the, uh, the regime. Um, and the other is the walkers themselves. It's all very well to go out for a protest march against X, whatever X happens to be, but that's not gonna change the world, uh, unless you do something afterwards. And that afterwards involves engaging with- in a democracy, in the political system. It involves voting for members of parliament to do things. It involves writing policy documents. It involves organization. It involves a whole lot of other things. So sending the signal that you're unhappy is one thing, but-

Dr. Rangan Chatterjee 30:27 Yeah

Shane O’Mara 30:27 ... uh, taking the action After you've sent the signal is something else entirely

Dr. Rangan Chatterjee 30:32 Yeah, for sure. And I get that in terms of actually making change. I f- just find it fascinating that so many things are done over walks, you know? And it... And you know, you, you dedicate a whole chapter in your book to social walking, which is incredibly fascinating.

Dr. Rangan Chatterjee 30:46 But you're a neuroscientist, and I know from doing some research on you that you have studied a lot of things about stress and depression and its impacts on particular parts of the brain, including the hippocampus. And that's an area that, that can get affected quite powerfully by walking. I wonder if you could expand.

Shane O’Mara 31:03 Yeah. So, uh, w- you know, I think one of the great discoveries of the, of, or rediscoveries of the last kind of couple of decades in neuroscience is the realization that the brain is a muscle, or functions like a muscle. Uh, it's plastic. If you work it, uh, y- it changes dynamically in response to, to what you do to it. If you leave it, it, it, it tends to atrophy. So, uh, the parts of the brain that are concerned with learning and memory, uh, is a part of the brain called the, the, the hippocampal formation. It's also the same part of the brain that's involved in the processing of information about stress. Uh, and it's also very badly affected by depression. And here's, I think, one of the amazing discoveries. Uh, we now know with absolute certainty, uh, y- as certain as we know anything in science, that lots of aerobic exercise, getting out and moving, walking lots materially affects the volume of the hippocampal formation. It gets bigger as the result of, of, uh, exercise, and the functions it supports get better as the result of, uh, exercise. And you can demonstrate this in all sorts of ways. We've done studies, for example, with, um, uh, sedentary, uh, college students, and we've made them do forced exercise regimes on bicycles on, on, on exercise bikes, and shown that, uh, molecules that are expressed in the brain, uh, wh- which float into the blood, uh, including brain-derived neurotrophic factor, go up. And memory in these students goes up. But even more dramatically, um, this capacity is retained right throughout life, so it's never too late. So, uh, y- I'll, I'll just pick on, on one very important study. Art Kramer's group in Chicago have taken, uh, a group of, uh, about 120 people in their early 70s, divided them into two groups, one who were just left to live their life as... randomly into two groups. They live their life as they always live it. And, uh, the other group are brought out for a walk three times a week, that's all, for about a mile and a half with a physiotherapist in small groups, groups of, of two. And, uh, they're followed for a year or so. And what you see is in the walking group, improvements in memory, improvements in attention, an increase in the volume of the hippocampal formation, uh, an increase in the amount of this amazing substance, BDNF, in the blood. And, uh, the 72-year-olds start to perform on psychological tests at the same level as 68-year-olds do. So y- in, in a very important sense, you've reversed the functional ageing of the brain. Whereas the other group who just continue their sedentary, tele-watching lifestyle, they continue on a pathway of decline.

Dr. Rangan Chatterjee 33:44 Yeah. I mean, that is incredible. And I, and I like the, the point you're making that it's never too late.

Shane O’Mara 33:49 That's the important thing. Uh, and I, I like to suggest, uh, that, uh, you only get old when you stop walking. You don't stop walking because you're old.

Dr. Rangan Chatterjee 33:59 Yeah. And I guess walking, and I, I'm thinking about, um, you know, people in my family now. Walking is something... I, I think this is actually part of the problem as well, and one of the reasons why I think you had to write this book is it's such a simple thing. Or is it... You know, we can, we can discuss whether it's simple or not.

Shane O’Mara 34:18 [laughs]

Dr. Rangan Chatterjee 34:19 Um, but it is s- it's something that many of us don't think about. We just put one foot in front of another [laughs] and we're walking. So we don't give it maybe the credence that it deserves, and we don't, we don't probably recognize its importance-

Shane O’Mara 34:32 Yeah, but I think what-

Dr. Rangan Chatterjee 34:32 ... until we lose it

Shane O’Mara 34:33 ... what you've said though is the key point, that we don't think about it. We just put one foot in front of the other. And that's the point I think that has gone wrong in how we've engineered our modern world. We've made it easier for the default to be to get into your car. What we should do is at all of the points of the day, whenever you're moving around, we should make it easy for you to just put one foot in front of the other without thinking about it.

Dr. Rangan Chatterjee 34:58 Yeah.

Shane O’Mara 34:59 That's what we need to do.

Dr. Rangan Chatterjee 35:00 Yeah. It, it, it's, it's mind-blowing. And, um, [laughs] as you, as you're, as you're describing all these benefits, I'm, I'm thinking about too, the f- I, I've, I went to Nairobi in 2011 for the first time. I'd never been to Africa before, never been to Kenya. And my wife's, uh, father, so my father-in-law, has a lot of his family living out there, and they are Jaines. And it's really interesting that, you know, the environment in Nairobi is certainly not set up for walking. There's a lot of... It's a busy city-

Shane O’Mara 35:25 Yeah

Dr. Rangan Chatterjee 35:25 ... with lots of cars. But this Jaine community, they have a center. And every evening at sort of dusk time, everyone in the community seems to congregate there. And for about an hour they've got this track. They all walk together for an hour together, just in, I wouldn't say in meditative silence, but it's a very quiet, it's a very reflective time. And, and because it's done in a community, because there's other people there, I think it attracts people, so they come each day. And I guess there's social connection, there's seeing your, your friends, your family, but there's something about that daily walking together, uh, which is, which is extremely powerful I think. If y-

Shane O’Mara 36:03 And, and you see this in Italy. Uh, in Italian towns they have, uh, uh, the wonderful phenomenon of the passeggiata.

Dr. Rangan Chatterjee 36:10 Right.

Shane O’Mara 36:10 Uh, at 7:00 or 8:00 in the evening in these car-free centers, people come out for a walk around together. It's an amble. They talk to each other. They see each other. Uh, if you go to, uh, some of the, the, uh, uh, squares in Rome you'll see it happening. But you particularly see it in, in the smaller towns. Uh, it's, it, it happens in Sicily. And, like, it's, uh- I think, you know, you're, you're hitting on something really important there that this time that we can gather and chat and talk, uh, free from the clamor of the day, and we can have also this wonderful thing, companionable silence.

Dr. Rangan Chatterjee 36:48 Yeah.

Shane O’Mara 36:49 Um, it really gives you a great opportunity just, you know, sort things out in your head.

Dr. Rangan Chatterjee 36:53 Yeah. And I guess in many ways it's never been more important than in the busy distraction-filled 21st century in which we now live, where, you know, many of us, uh, you know, any time we have a bit of downtime, we pick up our phones. We're, we're consuming, we're reacting. We are, um, you know, we're not alone with our own thoughts, and I think there is something powerful about walking. I know you certainly talk about this. I've written about this in the past as well, about creativity and what happens. When I was writing my books, and I'm, I'm... I, I don't want to put words in your mouth, but I would guess it was the same. If you're coming across writer's block, what do I do? Put everything down, go outside for a walk. You come back and before you know it, problem solved, right?

Shane O’Mara 37:32 Yeah, you're recharged. Uh-

Dr. Rangan Chatterjee 37:33 Yeah

Shane O’Mara 37:33 ... and, and in fact, I, I wrote a lot of this book by making notes on a page of my, on pages at my kitchen table, numbering those pages, and then going out and walking with a dictaphone and, uh, dictating it. And-

Dr. Rangan Chatterjee 37:45 Wow

Shane O’Mara 37:45 ... what, what you often find, uh, apart from getting the weird looks, uh, [laughs] as you're, you're going along, um, is that you talk, uh, far past the notes that you've made, and thoughts come to you that wouldn't have come to you had you been sitting at your keyboard, and then you end up with this big slab of text which is, has too many pauses in it, and-

Dr. Rangan Chatterjee 38:05 Yeah

Shane O’Mara 38:05 ... all the rest of it needs to be edited. But, uh, um, this is something that the m- many of the great writers of the ages, uh, have done. Um, you know, ph- philosophers like Immanuel Kant, for example, enormously productive. He would go, and you could set the clock by him, apparently, in Regensburg. Um, 3:00 PM every day he went for a two-hour walk, and then he came home and he wrote. Uh, Bertrand Russell, um, the, uh, the great philosopher, uh, would, uh, went for long walking holidays and enjoyed the feeling of, of, of, uh, not being in pain from 30-mile walks. But, uh, for his regular writing, he would get up, uh, make a few points on a page, go for an hour's walk, and then come back and compose. Stephen King, the novelist, um, in his book on writing, describes how, uh, he goes for very long country walks before he starts writing every day. It really, really does help.

Dr. Rangan Chatterjee 39:01 Yeah. Do we know the mechanisms by which we become, you know, more creative and we can solve problems when we go out? We take a break, and we go out for a walk. Do we know exactly what is going on there?

Shane O’Mara 39:14 So I think, uh, there are probably two or three different things going on here. So I think we have a misperception about how we problem solve, uh, and we think problem solving is active. It's time on the task. It's banging your head against the problem. And actually, uh, when we look at how the brain, uh, operates, d- we have what's known as a, a, a kind of a, a default mode, sometimes called the default mode network, where we're actually zooming back out. We're looking at kind of the bigger picture, and to do that, we're not engaged with the environment. And then we have what's called a task positive network, where we're focused on the thing. Um, and creative problem solving happens best when you're able to flicker between these two states, where you're, you're looking at the forest, then you're looking at the trees, and then you come back out, so you're searching for the pattern. And I have the suspicion, um, although I, I, I can't prove this, but I, I, I would hope, uh, that we would be able to soon, that one of the things that happens when you're walking is that you're able to engage in kind of an, uh, an active idle mode of thought, where you can flicker in on the problem, focus back out from it, hone in on it again, and come back in and out, and walking facilitates this kind of rhythmic, um, uh, focusing, defocusing on, um, on a problem. And I, I also think there's another thing going on. Um, when we're sitting as we're doing now, our brain doesn't have to work very hard. Uh, it doesn't have to work to maintain posture. Uh, when we stand up, one of the first things you have to do, uh, or one of the first things you see is our blood pressure changes, our heart rate changes, our, our breathing changes, and the brain has the particular job of keeping you stable. Um, so there's a lot more activity going on. So I, I think what's also happening when you're up and about, uh, more of the brain is active, and ideas that would be kind of just below the level of consciousness previously are now just being brought above and into consciousness because the brain is a bit more active.

Dr. Rangan Chatterjee 41:18 Yeah.

Dr. Rangan Chatterjee 41:18 And you mention at one point in your book that actually when we walk, other senses are heightened.

Shane O’Mara 41:24 Yeah. Yeah.

Dr. Rangan Chatterjee 41:25 Which I found... You know, it, it kind of makes sense. Um, I think what, what... a lot of it intuitively makes sense, but it was-

Shane O’Mara 41:32 But only when you say it [laughs] .

Dr. Rangan Chatterjee 41:33 Only when you say it, exactly. You don't think about it.

Shane O’Mara 41:35 Yeah.

Dr. Rangan Chatterjee 41:35 So what, what happens to all these other senses?

Shane O’Mara 41:37 Yeah. So a- again, you know, I think we've had this kind of view of how the brain works, which is, which is manifestly when you think... A- again, when you say it out loud, it's wrong. Uh, we think about the brain as, as something that passively takes in information from the outside, does something to it, and then we engage in a motor movement. But actually, the world is too complex for us to do that. Uh, and instead, a better way of looking at the brain is that it's, it's kind of information hungry. It, it's, uh, predicting things continually that are about to happen, and it's searching for information about the world to allow us to predict what we're going to do next. Uh, and it, it's engaged in the generation of, of possibilities, and it does this all the time, uh, when we're moving around. And if you, if you imagine, for example, you're a cat, uh, imagine you're a mouse, uh, and I use this example in, in, uh, uh, in the book. As a mouse, you don't want to get eaten. As a cat, you want to eat the mouse. Uh, so you're walking around, and your job as the mouse is to detect the presence of the cat. Um, and what you find in the mouse's brain when it's moving like that, uh, activity in its visual areas are heightened. Activity in its, um, areas that are concerned with, with hearing and all of those parts of the brain are, are heightened when it's in movement. They're not when it's not moving, and the same is true of the cat. Uh, because when you're moving, that's how you're gonna capture your prey. Uh, you, you don't capture your prey passively if you're a cat.

Dr. Rangan Chatterjee 43:04 Yeah.

Shane O’Mara 43:04 You're, you're a predator. You hunt. Uh, so it makes sense that, uh... And you know, again, think about humans on- out on the, the African plains, uh, 100,000 years ago carrying a, a, a fairly small spear. Is that yellow thing moving over there an antelope? In which case, I can go after it quickly. Or is it a tiger, and should I run away? [laughs]

Dr. Rangan Chatterjee 43:25 Yeah.

Shane O’Mara 43:25 Or can I run away? You need to make these decisions really, really quickly. They have to be really, really fast. So a k- a selection effect in favor of a brain that anticipates, uh, what's about to happen makes a lot more sense.

Dr. Rangan Chatterjee 43:38 I mean, that, that is incredibly, um, deep on one level because in, in many ways what you've just articulated is saying that maybe if we're sat down all day or we're certainly not walking, maybe our brain is only in first gear, and maybe to get into second, third, fourth, and fifth gear, maybe we need movement. We need walking. So if we're living sedentary lives, if we're sat down in our car to get to work, if we're sat at a desk all day and we sit down to eat our lunch at our desk, and we come back and we sit on the sofa in the evening, that for many of us maybe our brains have not got out of first gear.

Shane O’Mara 44:15 No, no. And, uh, the weird thing, of course, is that, uh, sitting around all day is tiring. [laughs]

Dr. Rangan Chatterjee 44:20 Yeah.

Shane O’Mara 44:21 Uh, and then you come home after not having done, uh, a day digging ditches, uh, you're s- sitting-

Dr. Rangan Chatterjee 44:27 Yeah

Shane O’Mara 44:27 ... at your computer, and you're exhausted. And the reason you're exhausted is because, uh, our bodies and brains need movement, uh, and, and that m- movement generates all sorts of wonderful molecules, um, that feed back on our sense of wellbeing that, that facilitate, uh, good things in terms of our musculature, in terms of our heart rate, and in terms of what's going on in the brain. So actually, somehow we need to break this. Uh, I don't, I don't have a solution for it except to say that we right at the outset need to bake into design principles for work, for buildings, for e- all the things that we do-

Dr. Rangan Chatterjee 45:04 For schools

Shane O’Mara 45:05 ... for schools. Absolutely. Um, no question about it, the facilitating movement, um, and, uh, making sure that much more movement happens. The other thing, of course, we, we have to do is, is, uh, honor sleep. You know? The, the-

Dr. Rangan Chatterjee 45:18 Yeah

Shane O’Mara 45:18 ... two things that, uh, will do the best for your mental health and for your physical health is to get lots of walking in, get lots of proper quality sleep.

Dr. Rangan Chatterjee 45:27 Yeah.

Shane O’Mara 45:28 I, I don't deal with that in this book, but there are many excellent books-

Dr. Rangan Chatterjee 45:31 I've dealt with that, I might add too [laughs]

Shane O’Mara 45:32 ... and you've written. Yeah.

Dr. Rangan Chatterjee 45:33 But, but it's a great point.

Shane O’Mara 45:34 Yeah.

Dr. Rangan Chatterjee 45:34 It's such a good point, and again, you know, my wife and I this summer, we reflected on a lot of things in our, our, our children have moved school recently, and it's a bit further away. So the natural tendency would be or would have been to drive there, and we've made a little bit of a vow in the family that we are literally gonna be trying our very best every day to walk the kids to school even though it's probably 25 minutes. I know that, that, that is not long. You talk to a lot of people, and they'll be like, "You know, people all around the world walk way more than that to school every day." But it's guess- I guess it's how used we are to convenience and, and quick-

Shane O’Mara 46:10 Yeah

Dr. Rangan Chatterjee 46:10 ... short car journeys. But we made a big difference, and I think you have shared some research that suggests actually if we walk prior to doing some sort of intellectual task, we perform it better if we have walked just before it.

Shane O’Mara 46:25 Yeah. And we perform it more creatively, uh, which is the other thing. We generate more ideas. So a very simple way of demonstrating that is, you know, to take a common household object like a, a pen, for example, and I, I ask you to come up with as many uses for that as you can in the next three minutes. And you might come up with seven or eight uses. You might come up with 25 uses. Uh, people vary and reliably vary in, in, uh, in, uh, this capacity, but it's a very good measure of creativity. Uh, knowledge workers, creative artists, uh, high-performing scientists will typically come up with many more uses for a common o- object than, than, uh, somebody who's not, uh, working in those, those kind of domains. But here's the rub. Um, for 100 years or more, uh, psychology has explored creativity in people who come to a lab and sit down and do a creative task. Um, what psychology has not done is asked what would happen if we got people to move prior to getting them to do a creative task. And what you find is that if you have people do a short period of movement, walk for 5 or 10 minutes prior to them generating these cre- new creative ideas, they generate on average twice as many, uh, after having walked, uh, compared to those who are seated. And, uh, uh, the studies on this are very beautiful. They're very carefully controlled. There's one where they've, uh, had people sit on a treadmill [laughs] on a chair, and they've had them walk on the self-same treadmill, and again, you find the same thing coming through that walking either on the treadmill or walking around an environment, uh, you will on average generate about twice as many new ideas.

Dr. Rangan Chatterjee 48:05 Yeah.

Shane O’Mara 48:05 Now, here's the important thing. It's often suggested that creativity diminishes with age, um, and that doesn't appear to be entirely true. Uh, but, uh, what is certainly correct is that if you get elderly people or people who are older, in their 70s, to walk prior to a, a creative idea generation, they will generate twice as many ideas as sedentary 20-year-olds Who haven't walked. So it, I've already said it's never too late in terms of, of changing what happens in, in, uh, inside your head as, as a result of walking. Uh, neither is it too late where creativity is concerned.

Dr. Rangan Chatterjee 48:50 It's mind-blowing, isn't it? You ... We're, we're seeing benefits for our physical health, for our mental health, for our creativity. Um, how accessible is that? You know, walking before you do a task, you know, whether it's walking your kids to school, whether it's before we get in the office, whether it's simply a case of, you know, having a break at lunchtime where you go for a 10 or 15-minute walk. It is, it's not only that it's gonna make you feel better, it's gonna make you more creative, and so many of us are trying to actually become more creative, solve problems that we have in our lives, relationship problems, all kinds of things. It's always better after a walk.

Shane O’Mara 49:25 Yeah. So the trick, uh, at least the trick I use, uh, is write down the few bullet points of what it is that you're trying to do. Um, and that organizes your thoughts into a kind of a schema, and then just put it down and go for a walk and come back to it.

Dr. Rangan Chatterjee 49:41 Yeah.

Shane O’Mara 49:41 That's the way. Uh-

Dr. Rangan Chatterjee 49:42 So you kind of almost signpost it to your brain-

Shane O’Mara 49:45 Brain

Dr. Rangan Chatterjee 49:45 ... these are the four or five things-

Shane O’Mara 49:46 Things that I need to, to worry about

Dr. Rangan Chatterjee 49:48 ... or work on.

Shane O’Mara 49:48 Yeah.

Dr. Rangan Chatterjee 49:48 And then you forget about it-

Shane O’Mara 49:49 And do just for- go for a walk. And-

Dr. Rangan Chatterjee 49:51 And let your deeply-

Shane O’Mara 49:52 Do drink

Dr. Rangan Chatterjee 49:52 ... clever brain do the work for you

Shane O’Mara 49:54 ... do the work for you. Yeah.

Dr. Rangan Chatterjee 49:54 Yeah. Incredible.

Shane O’Mara 49:55 And, uh, if, if it hasn't worked as a result of the walk, sleep on it. Um-

Dr. Rangan Chatterjee 50:00 Yeah

Shane O’Mara 50:00 ... and, uh, y- you know, there's John Dos Passos, the novelist, uh, used to say whenever he had trouble with writing, he would let the committee of sleep solve the problem for him. Um, and, uh, it, it is clearly the case as well that for difficult problem solving, you know, uh, having a good night's sleep can often, not always, but can often facilitate the, the problem solving. And having had a, a good day of movement before sleep helps you sleep.

Dr. Rangan Chatterjee 50:28 Yeah. I, I think the, the powerful message for me in, in what you're talking about at the moment is that our brain is always trying to solve these problems for us if we allow it to.

Shane O’Mara 50:37 Yes.

Dr. Rangan Chatterjee 50:38 And it's very powerful what you said, the, the two most important things we can do for our mental health is sleep well and walk lots.

Shane O’Mara 50:48 Yes.

Dr. Rangan Chatterjee 50:49 And they're things that actually really are available to so many of us. I know many people struggle, uh, with their sleep, and I think that the human being's default state is to be able to sleep, and generally speaking, I would say in, in my, uh, many years of clinical experience, I would say that the majority of people who are struggling with their sleep are usually doing something in their lifestyle that they do not realize is affecting their ability to sleep at night.

Shane O’Mara 51:14 Yeah.

Dr. Rangan Chatterjee 51:14 It's very ... You know, you do get primary sleep disorders, but by and large, I think it's, it's rare c- compared to the people who are, who are struggling because, you know, they're not moving enough, or they're not switching off in the evening, or their stress levels are too high.

Shane O’Mara 51:27 Yeah.

Dr. Rangan Chatterjee 51:27 Whatever it might be. But walking and sleeping are two things that are available to us.

Dr. Rangan Chatterjee 51:31 You mentioned mental health, and I think that will be a, a perfect sort of place to go in this conversation, is how important is walking for our mood, for our happiness, and for our overall mental health?

Shane O’Mara 51:43 Yeah. So the, there, there are two different ways of looking at this. So, uh, l- let's look at it as a kind of on the positive side first. Um, if you ask people to rate before they go for a walk how, how they're feeling now, uh, on a scale of one to five. They might say, "I'm feeling at around about a two." And if you ask them to rate how they'll feel after they've gone for a walk, they'll say, "Meh, probably about a two." Then you bring them out for a walk for 20 minutes, and you ask them to rate how they feel. They'll now say a four. Um, so we persistently underestimate how good a walk will make us feel. Um, and that's true even for people who dread walking, who dislike walking. Um, they, uh, underestimate just how much, uh, uh, the positive effect of a walking, uh, in kind of raising your, your mood, uh, at the moment. Now, a, for a, a much more difficult, uh, population or, uh, uh, or a more, a more difficult problem, uh, which is really a blight in, in modern life, major depressive disorder. Um, the, the, the lifetime risk for, uh, males and females combined is about 10%, uh, which is astonishingly high. Way, way, way too high. Um, and a recent remarkable study in Australia, uh, following I think about 35,000 adults, uh, l- looked at the risk of succumbing to major depressive disorder, uh, as a function of the amount of walking that the adults were doing. And for every level of walking above the most sedentary in the population, the risk of fall- or succumbing, uh, to depression falls. So the, the lesson there is that you're less likely if you do not have a, have major depressive disorder, you're much less likely to succumb to it if you are walking more. It's a simple prescription that kind of acts to in- inoculate you against the, the, the likelihood of, of succumbing to depression. Uh, what we don't know is whether or not walking, uh, is a good and a, a effective treatment for people who are already depressed. Um, there are no good studies that I've been able to find in, in the literature where this is concerned. Um, I have a, a sense though that, uh, when you look at the effect of very long-term walking, now I mean weeks, uh, in nature, what you see from the, the kind of deep case studies that have been done, uh, people's, um, the, uh, whole series of inf- inflammatory factors in the blood, the interleukins, and a bunch of other things, they all fall and fall really dramatically. Um, and it-

Dr. Rangan Chatterjee 54:21 After walking

Shane O’Mara 54:22 ... after walking substantial periods, you know, so for four or five or six weeks.

Dr. Rangan Chatterjee 54:27 I mean, uh, I think on that point, I think just to really amplify it We've, we've spoken many times on this podcast before how chronic unresolved inflammation is at the heart, is at the root cause of so many of the chronic problems that we see today-

Shane O’Mara 54:42 Exactly, yeah

Dr. Rangan Chatterjee 54:42 ... whether it's, uh, many cases of depression, whether it's type 2 diabetes, high blood pressure. Um, obesity is an, uh, is an inflammatory disease on, on so many levels.

Shane O’Mara 54:51 Yeah.

Dr. Rangan Chatterjee 54:51 And what you've just said is that prolonged periods of walking can have an anti-inflammatory effect-

Shane O’Mara 54:58 Effect

Dr. Rangan Chatterjee 54:58 ... on the body.

Shane O’Mara 54:59 Absolutely. Yeah, yeah. There's no question about this. Uh, the, the problem is, uh, few people have the capacity or, or, uh, the means to, to undertake a six-week walk, uh, in the wilderness.

Dr. Rangan Chatterjee 55:12 Yeah.

Shane O’Mara 55:12 Uh, and the, the, there's an ethical issue of course, if you've got somebody who's, who's succumbed to major depressive disorder, they need treatment and they need treatment now. Um, organizing a nature walk for them and, uh-

Dr. Rangan Chatterjee 55:24 Yeah

Shane O’Mara 55:24 ... doing this over a six-week period is, is, uh, would be a, a very, very difficult thing indeed to do. But, um, I think that the kind of, the more causal issue, uh, still i- is there, we, we see in those people who do these very long periods of walking, all these inflammatory factors fall in their blood. Uh, and Ed Bullmore and others, um, have, uh, posited the kind of theory that, uh, one of the key drivers of depression is inflammation in the brain.

Dr. Rangan Chatterjee 55:55 Yeah.

Shane O’Mara 55:55 And his recent book, The Inflamed Brain-

Dr. Rangan Chatterjee 55:57 Yeah

Shane O’Mara 55:58 ... actually argues that this is the case. And, and you see, and, uh, we've been doing studies on this in humans, uh, and others, uh, uh, uh, or sorry, humans who are treated with, uh, drugs like interferon alpha for, uh, uh, cancer and other things become ver- or in hepatitis C, they, they become, are often become very, uh, acutely depressed as the result of the treatment with inter- interferon alpha, which is a, a pro-inflammatory, uh-

Dr. Rangan Chatterjee 56:25 Yeah

Shane O’Mara 56:25 ... cytokine. So there may well be, uh, you know, w- at least one sub-class of major depressive disorder, which is inflammatory, uh, or inflammation related.

Dr. Rangan Chatterjee 56:35 Yeah. I, I interviewed Ed, um, I don't know, six, nine months ago or so on this podcast. We had a great conversation. People really responded very warmly to, to our chat. And, um, I think mechanistically we can now start to put these things together and understand, yes, we want more data, of course. We always want more and more robust research. But I think mechanistically there's enough there to, to be suggesting that, you know, well, walking potentially could be used as-

Shane O’Mara 56:58 Yeah

Dr. Rangan Chatterjee 56:58 ... you know, an adjunct at least.

Shane O’Mara 57:00 Yeah.

Dr. Rangan Chatterjee 57:01 You have spoken about two hunter-gatherer groups in the book, which I find super fascinating because I always think when we can go back into our evolutionary history, observe how humans have lived, how they've evolved, how we've evolved, how we've thrived in a, in a variety of different environments, it helps to put into perspective many of the problems we're having today. I have written about the Hadza tribe, um, but more specifically in relation to their diet and in terms of the amount of fiber they're getting and the impact it's having on their gut microbiome. But you shared some insights on the Hadza tribe and another tribe as well actually, that I found very surprising. I wonder if you could elaborate on them.

Shane O’Mara 57:38 Yeah. So the, the other tribe are the Tsimane in, uh, South America. Um, and the average 80-year-old Tsimane has, uh, the coronary artery health of a 50-year-old American, uh, because, uh, they spend so much time, uh, out and about and moving. Um, and, uh, what's, what's remarkable is, uh, you know, when you look at the, the kind of diets that they have, they certainly have meat in their diet, there's no question about that, but they have almost no processed food, or basically have zero processed food. They have a very high fiber diet. Um, they forage for nuts and berries. Uh, and uh, the, the sweeteners they use are typically either crushed fruits or, uh, uh, honey. Um, and, uh, their calorie intake is typically lower than, uh, the calorie intake of a, of a Westerner. Um, it, it's not that they're burning more energy. In fact actually when you look at the, the amount of energy burned by, uh, a Hadza or a Tsimane, it's, it's, uh, more or less the same as a, a Westerner. And w- we have-

Dr. Rangan Chatterjee 58:41 That's, that's, that's really interesting, that. Just say that again because I think that will surprise people.

Shane O’Mara 58:44 Yeah. And I was just gonna elaborate on it. So the, the amount of energy they burn is approximately the same as a, as a, as a Westerner. And the reason for this is that we overestimate the effects physical exercise have on energy burn, uh, and our, on our metabolism during the, the course of the day. So here's an easy way to think about it. Uh, the, the, the kind of recommendation for males is that they consume 2,500 calories per day. So let's call that 2,400 for the sake of, of, uh-

Dr. Rangan Chatterjee 59:13 Easy maths

Shane O’Mara 59:14 ... easy maths. Uh, so that's 100 calories, uh, in a, per hour for a 24-hour cycle. That 100 calories has to, uh, take care of your breathing, uh, your heart is beating 60, 70 times, uh, a minute or whatever it happens to be. Um, your brain burns an astonishing amount of energy. 20% of the, the cardiac output of the heart goes to the brain. Uh, and the brain needs energy being pushed into it all the time. The liver burns an enormous amount of energy. Um, and the energy that we use for running and all of these other functions turns out to be a very limited amount of the energy that we burn during the course of the day because housekeeping in our body, uh, absorbs so much of it. So what happens in, in these, uh, other groups is they just eat less. Uh, and the calories that they eat t- or the, the, the, the sources of calories come from foods where the available calories require extra work by the body. So if you're eating calories that are bound up in fiber, uh, your body has to work to extract those calories. Whereas, you know, you get a cheesecake, you get the hit from the cheesecake within- [laughs]

Dr. Rangan Chatterjee 1:00:25 Yeah

Shane O’Mara 1:00:25 ... a couple of minutes. Uh, so the highly processed foods that we're consuming really are a, a, a major problem. Um, what we really need to do is, is to try and shift away from the, the, the very highly processed foods, uh, in favor of foods that are, are, uh, where the calories are a little bit less accessible, where we have to work a little bit harder. Um, and I, I, I describe it in the book the, ironically, there's a diet that's used in lab animals, uh, and its nickname is the Western diet. [laughs] Uh, and the Western diet is amazing. Um, it's a, a, a diet that consists of a, a fat and sugar kind of, uh- Uh, mixture

Dr. Rangan Chatterjee 1:01:03 Cumber, yeah

Shane O’Mara 1:01:04 ... cum, uh, and rats go nuts for it. Um, they will eat it until they are bloated. Um, and humans love this stuff as well. We call it ice cream.

Dr. Rangan Chatterjee 1:01:14 [laughs]

Shane O’Mara 1:01:14 Uh, we call it, uh, cheesecake. Uh-

Dr. Rangan Chatterjee 1:01:17 Pastries

Shane O’Mara 1:01:17 ... we call it chocolate. Uh, um, if you have... We don't eat spoons of sugar. Uh, it'd be quite disgusting thing to do. Uh, we don't eat spoons of fat. But if you mix fat and sugar together in the right proportions and you emulsify them just right, they become highly palatable sources-

Dr. Rangan Chatterjee 1:01:36 Yeah

Shane O’Mara 1:01:36 ... of direct energy that we can eat really, really easily. Uh, and this is actually the problem. So a sugar tax to my mind, you know, might modify behavior a bit. It might take down the, the, the amount of sugar in a, in a fizzy drink. But actually the issue is, is to do with something much more subtle to do with the, the fat-sugar ratios that we're, we're consuming.

Dr. Rangan Chatterjee 1:01:58 Yeah. And as I said many times before, the, the, the thing that is consistent with many populations around the world who seems to have really good health outcomes when we look at their diets, is that they're having minimally processed foods.

Shane O’Mara 1:02:11 Yeah.

Dr. Rangan Chatterjee 1:02:12 That seems to be more consistent than whether we're looking at the fat content or the carb content or, you know, other, any other sort of reductionist type approach we might take. Generally speaking, they're minimally processed, and I guess that already fits in with what you're saying, is that there's a bit of effort that we have to use in our bodies to actually extract the energy from them-

Shane O’Mara 1:02:30 Yeah

Dr. Rangan Chatterjee 1:02:30 ... in which we're trying to do.

Shane O’Mara 1:02:31 So think, think about the smoothie. Don't eat the smoothie or drink the smoothie. Eat the fruit-

Dr. Rangan Chatterjee 1:02:36 Yeah

Shane O’Mara 1:02:37 ... [laughs] that goes into the smoothie. It's better for you, and, and your body has to work a bit harder to get the calories out of it.

Dr. Rangan Chatterjee 1:02:42 Yeah, for sure. Just going back to energy expenditure in these hunter-gatherer tribes. Um, are you saying that actually when we walk or when we run, we're not burning as many calories as we think we might be?

Shane O’Mara 1:02:57 Absolutely, yeah. Uh-

Dr. Rangan Chatterjee 1:02:59 So, so this whole idea that, oh, you know, I went to the gym after work so I can now chill out on the sofa and actually treat myself with, you know, A, B or C.

Shane O’Mara 1:03:08 It's even worse than that because-

Dr. Rangan Chatterjee 1:03:10 [laughs]

Shane O’Mara 1:03:11 ... uh, uh, you've gone to the gym. Your body thinks, "Hmm, I've persistence hunted. I deserve a reward." [laughs] Uh, so you, you've done your hour of running and you've run down the antelope and there's the meat, [laughs] right? So, uh, actually your body is saying to you after exercise, uh, we're gonna have a period of inactivity now. So, uh, you, you have this phenomenon known as exercise induced inactivity. And during that period of inactivity, especially in the evening, um, we're much more likely to eat and we're also likely to feel hungry because, of course, uh, uh, the hunger hormone, uh, ghrelin is, uh, uh, increased in our, in our blood, uh, in the evening before we go. So this is another reason why we should go to bed on time, is, uh, as we stay up, this hormone is there and it makes us want to eat. Um, but we, we do have this exercise induced inactivity phenomenon.

Dr. Rangan Chatterjee 1:04:05 So to, to expand that even further, in some cases, I need to be careful how I word this, but in some cases, could it be that going for your run after work or going for your intense gym session after work may potentially be counterproductive if it then leads to you, um, feeling that you've expended more energy than you had, it leads to you feeling more hungry and eating more than you otherwise would have done? Could, could in some cases-

Shane O’Mara 1:04:33 That can happen, and-

Dr. Rangan Chatterjee 1:04:34 Yeah

Shane O’Mara 1:04:34 ... y- yeah, you have a psychological license effect. Uh, so what you really have to do is look at the total energy expenditure across the day, you know. So if you're engaging in very little activity, you're sitting down all day, you do this big spike of activity, and then you're back again, um, of course you're gonna, uh, eat more. Whereas if you're engaging in high levels of activity during the course of the day, distributed, excuse me, distributed across the day, that would be better for you 'cause that's what we're designed to do. We're designed to mooch about more or less every hour- [laughs]

Dr. Rangan Chatterjee 1:05:04 Yeah. And, and-

Shane O’Mara 1:05:05 ... during the course of the day

Dr. Rangan Chatterjee 1:05:06 ... that echoes many studies we're seeing now, which are suggesting at least that you really can't outdo the, the nemesis of sitting down all day simply by going to the gym for one hour after work.

Shane O’Mara 1:05:15 Yeah. No, it doesn't work.

Dr. Rangan Chatterjee 1:05:17 Yeah.

Shane O’Mara 1:05:17 It, it just simply doesn't work like this. Yeah.

Dr. Rangan Chatterjee 1:05:18 And again, um, just to be super clear, I'm not telling people, and I don't think you are either, not to go to the gym after work.

Shane O’Mara 1:05:23 No. No.

Dr. Rangan Chatterjee 1:05:23 We're not saying that.

Shane O’Mara 1:05:24 No. We're saying look at the total energy expenditure-

Dr. Rangan Chatterjee 1:05:27 Yeah

Shane O’Mara 1:05:27 ... across your day and the total pattern of activity across your day. Uh, the gym can be a very important part of that, but if you're sitting down all day and then going to the gym for an hour, don't expect it to be a magic cure.

Dr. Rangan Chatterjee 1:05:40 Yeah.

Dr. Rangan Chatterjee 1:05:41 Shane, do we sometimes think that walking is a little bit too easy, it's a little bit too simple? Like we're looking for those, um, you know, we get more excited when we hear about the latest new gym fad that's come out, you know, the, the, I don't know, the boxercise or the-

Shane O’Mara 1:05:57 Cross trainer or the-

Dr. Rangan Chatterjee 1:05:58 ... the cross trainer or whatever.

Shane O’Mara 1:05:59 Yes. Yeah.

Dr. Rangan Chatterjee 1:05:59 And I, and I'm not, I'm not, I'm not absolutely, you know, I'm not trying to say that those things don't have value. I'm just saying have we missed what is sitting right in front of us by looking for more exciting forms of movement and physical activity? Is it, I- is it sitting right there in front of us, and have we... I don't know. Is it, is it reflective of culture and where we're at, that we're always looking for the new gimmick, the new thing that's gonna somehow, you know, reverse our, our, our biological age and get us fitter and healthier, whereas walking probably does all of the above and more?

Shane O’Mara 1:06:32 Yeah. Well, humans are a novelty seekers. There's no doubt about that. And we are status seekers. Of course, you know, people buy cool pieces of gym kit so they can look down on the people who don't have them. Um, but you know, we sh- we sh- we can leverage this in other ways. You know, th- one of the, or some of the best experiences you can ever have of walking are when you're walking with another person. Um, you know, so it is something that's very easy for us to do. It's in front of us. Um, but, you know, have a walking group, have a text group, uh, have a WhatsApp group or whatever it happens to be, and we can get the benefits of it very easily. And, you know, it's something that I think, you know, it should be engineered invisibly into our lives. It's, it's, it's not-

Dr. Rangan Chatterjee 1:07:10 Yeah

Shane O’Mara 1:07:10 ... you know, it should just simply be the default that we have it as something that we don't have to think about.

Dr. Rangan Chatterjee 1:07:16 Yeah.

Shane O’Mara 1:07:16 Um, but it happens naturally ... all the day, or all during the course of the day every day.

Dr. Rangan Chatterjee 1:07:22 Yeah, for sure. I was struck by something I heard you say once, um, and that was that we've been trying to get robots to be able to walk for a long period of time, but, but we just, we just can't, or we find it very, very difficult. And I think that really made me think, you know, is walking, is putting one foot in front of the other as simple as we think it is, or is, or is it actually deceptively complex in, in such a way that actually we can't train robots to do it?

Shane O’Mara 1:07:46 Yeah. It, it is horribly complex. [laughs] Uh, so it's easy to put a robot on wheels, and it can get around very, very well on wheels. Uh, but to get a robot to, to walk with the facility and ease that humans can, that has been a really, really difficult thing, uh, for, uh, roboticists to engineer. And again, we, we all kind of overlook the long period of training that we engaged in when we made that transition from being crawlers to walkers. It took about a year. Uh, we had to do 15,000 or 16,000 steps a day across all sorts of terrain. We fell 50, 70 times a day. Um, and, uh, we had to develop range and movement. We had to learn how to, uh, get balance. We had to learn how to carry the dolly to mommy when, or daddy, or whatever it happened to be when we were moving around. We had to learn that certain areas of the kitchen-

Dr. Rangan Chatterjee 1:08:39 Yeah

Shane O’Mara 1:08:39 ... were dangerous. You know, there were all those kinds of things that, that happen during that, uh, early phase, and robots don't get that training phase, you know? So it, it may well be the case that, uh, in future years, roboticists will just say, "Look, we just... We can defeat the problem if we can have l- robots that learn," and that's fine. Uh, or it's just easier to build things that have wheels or tracks.

Dr. Rangan Chatterjee 1:09:01 Yeah.

Shane O’Mara 1:09:01 Uh, and I suspect, you know, that's the route [laughs]

Dr. Rangan Chatterjee 1:09:04 Yeah

Shane O’Mara 1:09:04 ... that they would probably go down. Uh, 'cause that's r- they're easy to control in a way that, uh, uh, learning to walk isn't.

Dr. Rangan Chatterjee 1:09:13 It seems that at its core what we have here is that walking has got a PR problem. Um, your book clearly, In Praise of Walking, is trying to solve that problem and give it more PR. But I guess if, if we look at it as a PR problem, Shane, and we think about why, how we can make walking more attractive to people, if you were head of a advertising company and you had two minutes-

Shane O’Mara 1:09:41 [laughs]

Dr. Rangan Chatterjee 1:09:42 ... to actually, um, you know, talk about why all of us should walk more than we do, what would you say?

Shane O’Mara 1:09:50 I, oh, I would say you'll feel better, you'll look better, you'll think better. [laughs] All of those things will happen. Um, but unfortunately, I don't think it's a problem for PR. Uh, I, I, I really think it's a problem for the invisible system that's-

Dr. Rangan Chatterjee 1:10:02 Yeah

Shane O’Mara 1:10:02 ... around us. Why are our footpaths so narrow? Why do we give so much space, uh, to cars? Uh, why do we make it so difficult for elderly people to cross the road? Because, uh, we've engineered the, uh, the, the, the, the crossing, uh, time to be slower, uh, or to be faster than they can, they can walk. It's all of those kinds of problems.

Dr. Rangan Chatterjee 1:10:23 Mm.

Shane O’Mara 1:10:23 I, I, I think walking will happen naturally and easily if we facilitate it, and it doesn't when we don't. I, I, I, I, I, I do think we should all be walking more, but I, I think we individually run into a collective action problem-

Dr. Rangan Chatterjee 1:10:39 Yeah

Shane O’Mara 1:10:39 ... which is that we need our society, our urban world to be designed better for us.

Dr. Rangan Chatterjee 1:10:43 And, and this is a common theme that I think keeps coming up in the social commentary around health. It keeps coming up on this podcast. I had Chris Boardman, the Olympic cyclist on this podcast-

Shane O’Mara 1:10:53 Oh, yeah

Dr. Rangan Chatterjee 1:10:53 ... a little while ago, and again, he's very keen to try and raise the profile of cycling, and he's again trying to get these cities to make cycling easy.

Shane O’Mara 1:11:02 Easy. Exactly.

Dr. Rangan Chatterjee 1:11:03 So that people-

Shane O’Mara 1:11:04 Yeah

Dr. Rangan Chatterjee 1:11:04 ... you know, and the whole helmet issue is a separate issue, but Chris almost makes the case, I think, that actually let's make it safe so that people don't feel they have to put on helmets every time they get on a bike. Let's just make it easy. Let's make it, um, not something that's a real pain for people to have to do every time they want to go and cycle to work. Just make it the easy thing. And, you know, you're saying a very similar thing with walking. Let's engineer our environment so that the behavior we want is easy, so the behavior we want is the default option.

Shane O’Mara 1:11:28 Option. Exactly.

Dr. Rangan Chatterjee 1:11:29 That is what, that is what all these healthy societies around the world do.

Shane O’Mara 1:11:31 Yeah.

Dr. Rangan Chatterjee 1:11:31 That's what all the blue zones have. They're not trying to be healthy. The environment is set up in such a way that health is the easy option. Um-

Shane O’Mara 1:11:39 But it, the problem is a kind of a, a public health one, isn't it?

Dr. Rangan Chatterjee 1:11:41 Yeah.

Shane O’Mara 1:11:42 You know, public health isn't sexy, but public health has actually delivered the kind of great health gains of, o- over the, the, the past 100 or 200 years. We don't think about sewerage anymore. Uh, 200 years ago you could not walk the city, we couldn't have walked the city in, in Dublin or whatever because people didn't have a public sewer or, you know-

Dr. Rangan Chatterjee 1:12:02 Yeah

Shane O’Mara 1:12:02 ... they, they had chamber pots and they threw whatever out the window. Um, and there was disease rampant and all of the problems. So we, we've engineered that problem away. Um, and I think the challenge for architects, for town planners, and others is to do exactly the same thing, take the public health issue seriously, um, and engineer the way our cities and towns are designed so that people can actually walk easily around in them.

Dr. Rangan Chatterjee 1:12:29 Yeah, absolutely.

Dr. Rangan Chatterjee 1:12:30 Shane, in terms of your own behavior, I'm really intrigued. You've written this great book on walking. By writing that book, by going into the research, I think you already knew, but no doubt you, you dove a little bit deeper when you were writing the book. Did writing it actually change your behavior in any way? Are you doing anything differently now than before you wrote the book?

Shane O’Mara 1:12:51 Uh, I, I don't think so [laughs] is the honest truth. Um, I've always walked and walked lots. Um, uh, I think what's changed for me most in the recent years where walking is concerned is the presence of a pocket health pedometer in my phone, and I, I'm now very obsessive about checking the number of steps that I take every day. And I, and I'm much more conscious, I think, of how, uh- Good I feel on days when I've had lots of walking, and when occasionally, as it does happen in life, you have a couple of days where just it's raining too much, there's too many things happening, and I've just haven't managed to get my-

Dr. Rangan Chatterjee 1:13:32 Yeah

Shane O’Mara 1:13:32 ... 15,000 steps in, um, how bad, uh, I feel on... Well, not bad, but you know, just how slightly silted up I feel on those days.

Dr. Rangan Chatterjee 1:13:41 Yeah. Well, let's just briefly touch on technology here, 'cause I think you brought up a very good point. So you track your daily steps and, um, you know, whether we should be tracking our daily steps is something that people seem to have quite, um, yeah, quite powerful views about either way. And you made the case in the book that it's a good thing to track your daily steps, and one of the things I can see from hearing that story in terms of what you do is you're helping to almost tap into your own intuition. You're, you're seeing, "Hey, when I've done 15,000 steps, actually I feel better. My mood's better, I'm sleeping better," whatever it might be. And when I don't hit the same amount, actually, I don't feel as good. So I guess that's one thing I think a lot about is can we use modern technology in a way to help tap into our own intuition? It sounds like you're doing that.

Shane O’Mara 1:14:29 Yeah. Use it to support, uh, how you're functioning. You know, the, the reality is if I ask you, how many steps did you walk last Thursday fortnight?

Dr. Rangan Chatterjee 1:14:38 No idea.

Shane O’Mara 1:14:38 You've no idea. How many steps did you walk yesterday?

Dr. Rangan Chatterjee 1:14:40 No idea.

Shane O’Mara 1:14:41 No idea. We are not designed to remember e- either the periods of time that we walk for or the number of steps that we take because our bodies and brains are too busy doing other things. Uh, so we do need to record them, and it's easy to do. I cannot see a meaningful argument in the world, uh, uh, that says that we shouldn't. And what we know is when we look at the self-report data of what people say they do against what we know they've done because we've got the smartphone data, people under and overestimate really terribly-

Dr. Rangan Chatterjee 1:15:15 Yeah

Shane O’Mara 1:15:15 ... how many walking steps they take every day, how, how fast they walk, where they've walked. People are awful at this. Um, and that's fine. Uh, our brains are not designed to remember this kind of stuff, but we've designed little pocket-held robots to do it for us-

Dr. Rangan Chatterjee 1:15:29 Yeah

Shane O’Mara 1:15:29 ... so we should use them.

Dr. Rangan Chatterjee 1:15:30 I think the flip side is, and I guess blood pressure monitors are a great example of this, I think they work beautifully well for half my patients. The other half, they're actually problematic in the sense that if you're the kind of person who uses it once a week to see how you're getting on and it motivates you to make positive lifestyle choices, I think it's great. Some people, on the other hand, will check it three or four times a day. They'll really stress themselves out every time they see, you know, a, a slight increase in the reading. And actually for many of those patients, it starts to become counterproductive.

Shane O’Mara 1:16:00 Yeah.

Dr. Rangan Chatterjee 1:16:00 I don't necessarily think walking, um, tracking your walking steps is, is the same.

Shane O’Mara 1:16:05 I don't either. I think, I think, you know, this is a, a kind of a, just a passive record of-

Dr. Rangan Chatterjee 1:16:11 Yeah

Shane O’Mara 1:16:11 ... uh, what you're doing over the course of the day.

Dr. Rangan Chatterjee 1:16:12 I find it in-

Shane O’Mara 1:16:13 Yeah

Dr. Rangan Chatterjee 1:16:13 ... with my patients, I've found actually it's more positive motivating factor. Actually, it's like if they set a goal, um, of let's say they wanna do 8,000 steps a day, and if at the, uh, if by dinnertime they've only done 6,000 steps, often it- it's a motivator for them to go, "Hey, you know what? After dinner, I'm just gonna go get my-

Shane O’Mara 1:16:29 Just go out for a quick 20-minute walk.

Dr. Rangan Chatterjee 1:16:30 Yeah.

Shane O’Mara 1:16:31 Yeah.

Dr. Rangan Chatterjee 1:16:31 'Cause they wanna-

Shane O’Mara 1:16:31 And that's great

Dr. Rangan Chatterjee 1:16:31 ... they wanna meet that sort of-

Shane O’Mara 1:16:32 Yeah

Dr. Rangan Chatterjee 1:16:33 ... standard that they've set for themselves. The other thing I wanted to just briefly touch on at the end of this interview about, uh, technology is you mentioned all the benefits of going out for long walks, um, in terms of what it does for our brain and our minds. Now, I'm conscious when I ask this question that many people are listening to this conversation right now whilst out walking or out running, but is there something to be said for going out and walking without headphones in your ear, without, you know, losing yourself in music or a podcast?

Shane O’Mara 1:17:02 Yeah. So I, I listen to podcasts when I walk. Sometimes I, uh, when I'm, I'm walking, what I'll do is I listen to a podcast for the first half and I stop listening to it for the second half. Um, so I, I, I simply don't know. Uh, I, I-

Dr. Rangan Chatterjee 1:17:16 Yeah

Shane O’Mara 1:17:16 ... I, I, I think, you know, the, uh, the best experiences I've ever had of walking have been walking with other people. Um-

Dr. Rangan Chatterjee 1:17:23 Yeah

Shane O’Mara 1:17:23 ... you know. So I think if, if listening to the podcast gets you out for an hour that you would otherwise have spent sitting in a chair, go for it. I think it's great. Um, uh, if you're trying to problem solve, uh, if you're trying to think through a difficult problem, I think having the auditory distraction is a bad idea. Um, uh, especially if you want to have a quiet conversation with yourself about something.

Dr. Rangan Chatterjee 1:17:46 Yeah.

Shane O’Mara 1:17:46 You know, you wanna think through, "Why did I say that?" Or, you know, you know you're gonna have a difficult problem to deal with tomorrow. How do you approach it? What are the, the ways you're gonna, uh, approach the person you have to talk to about it? I think in, in those cases, but I think we just need to be a little bit self-conscious about this. Um-

Dr. Rangan Chatterjee 1:18:01 Yeah

Shane O’Mara 1:18:01 ... and we also need to think our ears need to rest from time to time, so maybe, you know-

Dr. Rangan Chatterjee 1:18:06 Yeah

Shane O’Mara 1:18:06 ... keep the, uh, the sound down a bit.

Dr. Rangan Chatterjee 1:18:08 Yeah, I love that. If you're trying to solve a problem, maybe you know what, go out with nothing on. But if you're just gonna sit at home, listen to a podcast, and you have an hour, why not go out and walk whilst you're listening?

Shane O’Mara 1:18:17 Yeah. Absolutely.

Dr. Rangan Chatterjee 1:18:17 Right?

Shane O’Mara 1:18:17 Yeah, yeah.

Dr. Rangan Chatterjee 1:18:17 So I think it's beautiful 'cause it's not like demonizing technology.

Shane O’Mara 1:18:20 Yeah. No, no.

Dr. Rangan Chatterjee 1:18:20 It's just sort of saying, "Hey, just think about what you're trying to achieve or, or what your current state of mind is, and then do the appropriate behavior."

Shane O’Mara 1:18:29 Yeah.

Dr. Rangan Chatterjee 1:18:31 Shane, I've really, really enjoyed chatting to you. Um, I think you've written a brilliant book. This podcast is called Feel Better, Live More. When people feel better in themselves, I think they get more out of life. I think this conversation in many ways is your, is very, very strongly making the case that when we walk more, we live more. Yes, it's the environment. Yes, w- we'd love it if urban settings and cities and workplaces and schools could be set up in a way that makes it much easier for all of us to walk. Having said that, I wonder if on an individual level you can provide some tips, some actionable tips that people listening to this podcast can think about applying into their own life immediately to improve the way that they feel.

Shane O’Mara 1:19:12 Yeah. So, uh, always have a comfortable pair of shoes close. You know, if, if you're wearing high-heeled shoes to work, keep a pair of runners under the desk, uh, so you can go out for a walk at lunchtime. Set your computer, if you're working at a computer, to have the alarm go off every 25 minutes, which I do, and get up and go for a walk around. Uh, if you find that you have to drive, uh, your car to somewhere, park a- as far away as you reasonably can and walk that extra distance. If you're taking the train to work as I do, get out two stops early and walk that last, uh, remaining distance. Um, those kinds of things, just very, very simple changes. If you're going out to get lunch at lunchtime, don't go to the closest shop. You know, use Google to help you. Uh, do the restaurants near me or the shops near me, and try and find somewhere new that's a little bit further away so that you just get in an extra 1,200 steps here, an extra 800 steps there, so that at the end of the day, somehow you've racked up 10 or 12 or 14,000 steps and you haven't thought about it at all.

Dr. Rangan Chatterjee 1:20:15 Shane, I love it. You've written a fantastic book. Thank you for putting all the research together in one place. Uh, keep on doing the incredible work that you are doing, and thank you for joining me today.

Shane O’Mara 1:20:24 Thank you. I've really enjoyed it. [upbeat music]