Instant Genius - Why walking more is the best thing you can do to boost your health

Episode Date: May 14, 2026

Over thousands of years, human beings evolved to walk upright on two legs, efficiently and over long distances. But these days, thanks to changes in our lifestyles, we’re becoming more sedentary than ever, and this is having profound effects on our health and well-being. In this episode, we’re joined by Courtney Conley, a doctor of chiropractic medicine, and Milica McDowell, a doctor of physical therapy and exercise physiologist, to talk about their latest book, Walk – Your Life Depends on it. They tell us why the oft-quoted 10,000 steps rule has no grounding in science, and was in fact originally, dreamt up as a marketing slogan to sell pedometers in the 1960s, explain the many things the way we walk can tell us about that state of our health, and give us some advice on what we should look out for when shopping for shoes that will help us get the most benefit from our daily walks. Learn more about your ad choices. Visit podcastchoices.com/adchoices

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scientists and experts talking about the most fascinating ideas in science and technology today. I'm Jason Goodyear, commissioning editor at BBC Science Focus. Over thousands of years, human beings evolved to walk upright on two legs, efficiently and over long distances. But these days, thanks to changes in our lifestyles, we're becoming more sedentary than ever, and this is having profound effects on our health and well-being. In this episode, we're joined by Courtney Connolly, a doctor of chiropractic medicine, and Melissa McDowell, a doctor of physical therapy and exercise physiologist, to talk about their latest book. Walk, your life depends on it.

They tell us why the off-quoted 10,000 steps rule has no grounding in science, and was in fact originally dreamt up as a marketing slogan to sell pedometers in the 1960s. Explain that many things the way we walk can tell us about the state of our health, and give us some advice on what we should look out for when shopping for shoes that will help us. get the most benefit from our daily walks. So, hello, welcome to the podcast. Thanks so much for joining us. Thank you for having us.

Thanks for having us. Oh, you're welcome. So today we're here to talk about your book, Walk, Your Life Depends on It. So as the title suggests, the book's all about the many benefits to our health that walking provides. And you even go so far as to call it Vitamin W,

which I thought was great. But as you say at the start of the book, you know, humans evolved to walk upright for long distances at a time, but thanks to developments in things like technology and changes in lifestyle the way we work, fewer and fewer are walking that much at all. But let's go right back to the beginning, you know. So what were the evolutionary advantages if walking upright, you know, as opposed to walking on all of our limbs, like I'd say chimpanzees do now? When you think about the evolution and what we have been designed to do. When we became a biped, so walking on two feet, a lot of things occurred because of

that. We were able to start using our hands, for example. We were able to have less sun exposure because we weren't on all fours. We were able to stand upright and see further. So all of these little evolutionary changes enabled us to walk for longer distances and to become more efficient. when you think about what really gets me excited is what has changed from our skeleton. There are a lot of evolutionary adaptations that occurred in our spine, for example, and at our knees and certainly at our feet. So when you think of the alignment of the big toe and the mobility of the ankle, all of these things we have adapted to be able to become very efficient walkers

and to walk for long periods of time. And unfortunately, what has happened, I think, is that we're not taking advantage of those things. We're actually moving less. We're walking less. And from an evolutionary perspective, that's a problem. Yeah, so let's get into the sort of nitty-gritty of that then. So how much should we be walking?

I know that's a bit of a difficult question. But everyone's going to have heard, which you write about, the 10,000 steps rule. Where did that come from? because it seems to have been around for an awful long time. It has been. It's been around since the 1960s. We like to say it's a marketing hangover from the Japanese Tokyo Olympics.

And the pedometer was first invented as a way to keep track of your steps. And the original device only went to 10,000. And so the name for the device was a 10,000 step meter. And that has hung around since 1960. What's exciting about that and one of the myths that we want to bust in this book and in our work with podcasts and other interviews, is that 10,000 has never been science-backed, and it's something that is often unapproachable

and discouraging to individuals. And so I'll let Courtney take it from here, but the numbers that are the ideal step counts are way lower than 10,000 for health benefits and longevity benefits. Yeah, when we were researching the book, when we found the average step count that most people are taking,

it was around 4,700 steps per day, which means that many of us are taking less that. So when you start looking at the numbers for someone who is considered sedentary, which is, you know, less than 2,500 steps a day, improving your step count to 3,800 steps can reduce your risks of getting things like dementia by 25%. That's a high number. And when you think about what that entails, 500 steps is about five minutes. So when I'm working with my patients and we're saying, you know, patients have been in pain or they have this very low step count. I'm like, listen, if you could just give me 10 minutes more a day, we could get you to that

marker of almost 3,800 steps a day. And now you're taking advantage of reducing the risks of dementia, the diabetes risk starts to decrease. So all these kind of really awesome things happen with these lower step counts. And so I think that's really important. And we need to be talking about this things. I always say on these interviews, you know, walking should be on every doctor's prescription pet. Yeah, that's really interesting because, you know, you'd think sort of, well, you know, of course, if we're more active, if we're walking more, that probably will lower our risk of things like cardiovascular disease. But yeah, as you touched on there, there's also risks of things like dementia. And even cancer, that was really surprising. Yeah, when you look at the step counts for

cancer risks, 5,000 to 7,000 steps, you can have a lower risk, 11% lower risk of cancers. When you jump that number to 7 to 9,000, it's a 16% lower risk of certain types of cancers. So I think the interesting conversation there, too, is the stacking of behaviors. Because when we start walking more, we talk about it being this physiological necessity. You're probably sleeping better. You're probably breathing better. So I like to think about walking as this foundation that when we get back to what we have evolved to do, It builds this platform for improving better overall behaviors.

And so I think that's a good conversation to have. Another thing I'd just like to ask you that you talk about in the book is sort of, so as we age, our balance tends to get a little bit worse. And our bone density decreases, you know, naturally. So obviously, this not only increases the risk of us falling, but also the likelihood of serious injury when we do so. And again, walking comes to the rescue. Yeah, I mean, I love this conversation. Walking stimulates every system in our body, our metabolic system, our nervous system, our cardiovascular system, our musculoskeletal system.

So when we walk, we put more loads through our feet, for example. So it's a good opportunity to maintain the bone health that we have. We also talk in the book about weighted walking, which is walking with, you know, with weight. Rucking is what it's sometimes referred to. Those additional weights can add additional loads through the system and help maintain bone health. And I think that's an entry point for people who haven't been strength training, for example. And it's a great opportunity from an education standpoint when we start talking about fall risk. Another part that's really key is the strength of the big toe flexors.

So not only, as Courtney is mentioning, are loading the bones, strengthening the bones, strengthening the muscle around the bones, we're able to have some very specific interventions that we call out in the book and instruct people how to do that can very specifically reduce their fall risk. So not only is the big toe a factor when it comes to falls, we also have a whole section in the book where you can self-assess at home, you can sort of be your own physical therapist or chiropractor, you can go through, some foot awareness drills that can help you identify if you do have any balanced deficits side by side. And then we introduce something called movement snacks, which are tiny little exercises you can do on your own that will help you reduce those deficits. So I like to think of it almost like a cookbook

where you can go to any chapter, find something to work on, play with it for a while, and then see what comes up. Yeah, I mean, I think we forget how important the foot is when we're talking about all of this. I mean, a big focus in the book is paying attention to your feet in realizing that when something bad happens to our feet, because the feet get weaker as we age, we lose strength in our feet as we age. And it is our feet that keeps us upright and balanced and able to walk long distances. And I think that's the one part of our bodies from a rehabilitative perspective and a, you know, strength perspective that most of us have forgotten about, that we're strength training our glutes and we're strength training our legs, but you need to strength train your feet.

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Let's have a look at the way we walk, you know, what's called our gate. So people might have heard of gate analysis before. You know, maybe they've been to a physician or something, a specialist, and they're had them themselves, or somebody in their family is. But, you know, what does that mean? What goes on when we're assessing someone's gate? We want walking gates to be efficient. So when you're watching someone walk, because we have evolved to walk very long distances, when you watch someone walk, it should be smooth. It should be easy. It shouldn't look like it's a struggle.

And so what happens is when our one foot hits the ground, the foot rolls through, we call it in the book kind of rolling the earth away. And then we have one stride and then we go on to the left foot. So a stride length would be the right foot to the right foot. There's a lot of biomechanical things that happen when someone's walking. And we don't think about that because it's subconscious. until something goes wrong. And when something goes wrong, that's the opportunity to really assess.

And that's a fun part of working through this book is we give you some techniques to assess your own walking patterns, whether that's using a phone or having a friend do some video analysis. You can actually really see what you're doing if someone just takes a momentary video of you. The other thing we encourage people to do is listen to their walking gate. And that's most easily achieved on a treadmill because you can actually hear if your walking pattern is even or if it sounds like a horse scalloping or if we're hearing scuffing as one of the feet are coming through. Those are the things that as clinicians we're able to pick out and create interventional programs for. But if you're just a regular

human being who's trying to optimize your gate, as Courtney said, to be more efficient, if you find any of those imbalances while you're doing a self-assessment, it's time to look a little bit further. You could also just listen to your family walking around their house. There's always that one family member where you're like, it sounds like someone is, you know, an elephant is trampling through the house. Those, those heavy gates, that heavy sound, walking should be soft. It should be smooth. And so those are the things that we want to look at. And that's important. In the book, we also give some walking drills to improve efficiency. And some of them might be surprising. One is thinking about walking taller, almost like you're trying to kiss the sky with

the top of your head. As Courtney mentioned, another is walking softer so you don't sound like a baby elephant trampling through the place. Another is increasing your walking speed, which is your walking cadence. And the one that surprises people the most is actually walking backwards, which is a very effective walking drill for improving your efficiency. So one of the things I thought was interesting that you mentioned in the book, you mentioned it there, walking speed. So you say that this is sort of, you even say it should be considered as kind of one of our vital health markers. So, you know, what do you mean by that? How does that work? When you go to the doctor, they take your vital signs. So they take your

temperature, your blood pressure. And there's a reason that they do that. Because if something is wrong there, it's flagged with the potential of, hey, there could be a problem in the future. And what walking speed has been touted as this sixth vital sign is because when we see patients, that have a slower cadence or they're walking at a slower pace. This can be an indicator, for example, of a diagnosis of dementia up to seven years in advance. That is an early intervention. If we can find these things seven years in advance, then we can start to implement proactive treatments for these patients.

A slower walking speed could also be an indicator of poor balance. maybe there's a weakness in the system and which can also indicate fall risk. So that's a very important factor to consider. And when you think about the speed that we're looking for, when you look at the research, you mentioned the cancer research. All of that research was looked at with these people walking at a certain pace. And that pace was 3.5 miles per hour, 3 to 3.5, which is pretty, fast. It's about 120 to about 135 steps per minute. So I'm always telling my patients, go outside,

walk for a minute, count how many steps you're taking in that minute and see where you lie. Because if that number is low, you can start to train it. And we give tips on that in the book, using a metronome and how to increase your pace. People don't realize how fast that is. You know, it can be, if you were to get on a treadmill and put your treadmill at 3.5 miles per hour or 4.0 and try to maintain that pace for 30 minutes, which is what the research will tell you to do, I think people would find that they probably need to start paying more attention to how they're walking and how fast they're walking. So what are some common problems people have in walking, you know, think with their feet? So you write about things like fallen arches and different, you know, bunions even and things like that.

You know, so what are some of the sort of headline things that we should be looking out for? I think when you start taking an assessment of your feet, the first thing you should do is look at them, which we don't often do. The widest part of your foot should be your toes. So if you were to look down at your foot, your toes should be the widest part of the foot. So if you were to see a bunyan, for example, which is a bump on the inside of the foot, or a bunion on the outside of the foot, hammer toes, any type of change in the toes, these are, again, signals for us. We should look at that and say, hey, why is this happening? Because bunions and hammer toes increase our risks of falls by one and a half to two times the risk.

it also alters the strength of the foot. So these are all things that can be worked on. I love how you mentioned it is an early warning sign, Courtney, and I think this anatomy conversation is also one as well. So when you are doing a foot assessment and you're seeing abnormal bony bumps or you're seeing abnormal positions, it's similar to that walking speed as an early warning sign for dementia, that we want to pay attention to it and do something about it sooner than later. And that does start with really acknowledging what kind of shoes are you putting those feet in? When we talked about the widest part of your foot should be your toes,

I would encourage everyone listening to this to go look at your shoes because the majority of footwear that is available to us is tapered at the toe. So it has the pointy toe. So if you were to take your foot, for example, and take a rubber band and wrap it around your toes, that's what your foot looks like in the shoe. And when you think about that from strength, from balance, it doesn't make sense. If we're trying to balance well and have good strong feet, that's going to happen when my feet can

splay and engage the ground. So a lot of the things we discuss are what is the right type of footwear that we should be using? and we don't want to compromise our foot function based on the footwear that we're using. Yeah, so let's go into that in a moment. But one thing that I was very surprised in, on the topic of shoes that you talk about, is huge numbers of us are wearing shoes that are the wrong size even. That's a great data point.

And every time we explain that to someone, people are generally shocked. So feet are measured in length and width by a device called the Brannick device, which is 100 years old this year. It was made in America. It has not changed its design in 100 years. And it is a gold standard for foot measurement unless you've got some sort of fancy like scanning technology. But over 60% of adults were shoes that are the wrong length. And that can lead to a host of problems. Blisters, abrasions. As Courtney was talking about earlier, some of the deformities that will start to see, foot pain, neurological issues, lack of balance. If you're in in the wrong-sized shoe, you're only doing yourself a disservice from your fall risk as well

as your walking capabilities. And that's super easy to solve because most adults would tell you, oh, I've worn a size 10 my whole life. It's been the same since I was a teenager. And what they're missing is just like other parts of your body, your feet are changing. They have increased muscle tone, decreased muscle tone, increased fluid volume, decreased fluid volume. All sorts of things affect the actual structure and anatomical shape of your foot throughout your lifespan. And so we highly recommend adults measure their foot at least once a year and then make sure that you're selecting different sizes of shoes based on the different shoe brands. A 10 in one brand is not a 10 in another.

And so you really need to take a closer look at this. So it's not impacting your foot health and then your overall health. Yeah, I think that the children conversation is also very important because the kids' feet are growing very, very quickly. And they're not going to give you feedback. They're not going to say, hey, mom, my shoes are too tight. So that is something that we definitely want to stay on top of at that younger age is every three months, every six months. You can even take out the factory insert of the shoe, which is the insert in most footwear, and then take it out of the shoe, put your foot on the insert.

And your foot should live within the factory insert. If the toes are expanding over the edge, if it's too short, you know when you put your foot in there, it's going to be too small. So let's have a look at, you talk quite a lot about types of shoes, which I thought was really, really interesting. Because, you know, we know if we go on a night out for several hours and we're wearing high heels, at the end of the night, our feet are going to hurt. But it turns out that a lot of sort of casual footwear, normal footwear,

isn't doing our feet any good either. So what are some of the problems there? Again, when you look at your shoe, it should respect the anatomy of the foot. So we define something called functional footwear. And functional footwear is a wide toe box. So the width of the shoe is the widest at the toes. It has a lower heel to toe drop. So basically, when we're standing barefoot, our heel on our toe are on the same plane. A low heel to toe drop would be a shoe. that has anything from six millimeters or less. And, you know, most of our sneakers and our trainers and our athletic footwear,

those numbers are higher. It's 8 millimeters, 10 millimeters. So we want to be able to identify those things. And then the amount of cushion on the shoe. I think this is a really important conversation because a lot of the footwear we're seeing now has maximal cushion. It's like they want you to like walk on a. pillow and we want to caution people about this because there's always a trade-off here.

When you put a shoe on that has all this cushion on it, you're going to be like, wow, this feels great. It's like I'm walking on a cloud and there's always a trade-off. And that trade-off is that we feel less. So there are thousands of receptors on the bottoms of our feet that are designed to feel the ground. It tells us how to stay upright and balanced when we walk. It tells us when our foot should be adapting to terrain to avoid falls, for example. And when you're standing on a lot of cushion between your foot and the ground, you compromise that sensory information.

So when we're looking and working with patients who have fall risk, who have issues with balance, the last thing we want to do is make it harder on them with a lot more cushion underneath their foot. So we will talk to them about using a more functional shoe with less cushion, working on the strength and skill and mobility of their feet so that we can avoid those types of problems. And we've identified essentially, as Courtney said, these three categories, of shoes. So a traditional shoe would be something that doesn't have any of the features she was just talking about. The functional shoe is the one with the wide toe box, lower heel to toe drop. And then we talk about minimal shoes. And that's a question we get asked about often of should I wear these? How do I get

into them? What does that look like? I've tried them and I had heel pain or I wasn't sure if I was doing it correctly or I bought a pair and I wore them 15 hours a day and now I have a discomfort. And so that third category is really a specialty category that's beyond the traditional footwear, that's beyond the functional footwear. And when we get into a minimal shoe, we're talking about a shoe that has the criteria, wide toe box, zero heel to toe drop. So the heel and the toe are completely flat. And then little to no cushion. If you take a shoe that's considered minimal, you can twist it, almost like you're wringing out a wet towel. And that is one of the features that really allows your foot to go through optimal biomechanics, but you have to earn the right to be in that type of

shoe. It requires a lot of mobility, and it requires significant strength in your internal muscles in your foot, as well as your calf and the muscles that support your lower leg. It's a great environment to improve your strength, not only at your foot, but the rest of your body. And with our patients, and we have a whole chapter in the book on this on how to transition into that footwear. It is very slow. It's five minutes. I was just working with a patient this morning. He's going to wear this shoe for five minutes. I told him, it's kind of like your training shoe. Think of wearing the shoe as like an exercise. You're going to wear this shoe for five minutes a day. And then you're going to assess how you feel that night in the next morning. Doing okay. Then you can

slowly start to increase your time, just like you would if you were strength training any other part of your body. that's how we make that transition and that's how we can really improve people's strength from the ground up without people saying well my heel hurts or my foot hurts there's a way to do it correctly yeah so say someone who's listening thinks well you know you've convinced me i definitely need to start walking more but you know there could be all sorts of reasons that have stopped them you know perhaps they've been sick perhaps i've had an injury perhaps they have just been sedentary for an awful long time. You know, in the book, you share a lot of ways in which we can get into this and a lot of

sort of techniques and ideas and strategies that we can try to get ourselves, you know, back walking again, essentially. So what are some of the top tips you'd like to share? It's such a great question. When we were designing the programs, we were thinking of it along our whole patient spectrum. So there's three different programs in the book. So one program is for patients who have been in pain who have a very low step count.

And so we have eight weeks of saying, this is going to be how you're going to start. We've introduced something called a micro walk, which is a five-minute walk that you can implement several times a day. It's less duration, but it's more frequency. And it's a very safe intervention for people who aren't used to being on their feet for longer periods of time. Then we have a build program, which is that second program, which we think a lot of people will live. That's that 5,000 to 8,000 step count, which is, that's our sweet spot. If we want to tap into the health benefits for longevity, that five to 8,000 steps is where we

want to be. And we've given, you know, movement snacks that we can work on during those eight weeks to improve mobility of the foot, to improve strength of the foot. There's different gait drills in there. But then we also have our patients that are, you know, our ultra athletes. And they're saying, why walk when I can run? There's also a place for them because walking is a necessity. It's not in lieu of. So in the boost program, we talk about incorporating strength training and walking lunges, for example, and how to build power when you're walking. So I really think that no matter where someone sits along their walking journey, that there's a place where they can find to either improve or maintain their health.

Thank you for listening to this episode of Insom Genius, brought to you from the team behind BBC Science Focus. That was Courtney Connolly and Melissa McDowell. To discover more about the topics we've just discussed, check out their latest book, Walk, your life depends on it. If you liked what you just heard, then please do consider subscribing to Instant Genius on your preferred podcast platform. If you'd like to see our guests and hosts in person,

then why not check out our YouTube channel at ScienceFocus. The current issue of BBC ScienceFocus magazine is out now. Pick up a copy wherever you buy your favourite magazines or download us on your app store of choice. You can also find us on Apple News or online at sciencefocus.com. Thank you.