09/23/2016

Myth-Busting Your Fitness Routine

17:04 minutes

Woman walking, via Shutterstock
Woman walking, via Shutterstock

You’ve probably heard fitness experts say that 10,000 steps should be your goal if you want to reap the daily benefits of exercise. But did you ever wonder where that number comes from? It must be backed up by scientific evidence, right?

Actually, the goal of 10,000 steps originated with a type of Japanese pedometer sold in the 1960s. It’s name, “manpo-kei,” translates to “10,000 steps meter.” And over the next several decades, 10,000 steps became the number around which scientists conducted fitness research. But Euan Ashley, an associate professor of cardiovascular medicine and genetics at Stanford University, points out that there isn’t a ton of evidence to suggest that 10,000 steps is the sort of magic number health experts think it is. It’s become more myth than science.

[Alan Alda hits the gym — the empathy gym, that is.]

And that’s not the only popular fitness claim with tenuous footing. Only a handful of studies have looked at the benefits of the standing desk, despite its near-universal acceptance as a healthy workplace habit. Bethany Barone Gibbs, a researcher from the University of Pittsburgh who has conducted some of those studies, joins Ashley to discuss the thin veil of evidence surrounding these fitness credos.

Segment Guests

Euan Ashley

Euan Ashley is an associate professor of Cardiovascular Medicine and Genetics at Stanford University.

Bethany Barone Gibbs

Bethany Barone Gibbs is an assistant professor of Health and Physical Activity at the University of Pittsburgh.

Segment Transcript

IRA FLATOW: This is Science Friday. I’m Ira Flatow. Last week on the program, we talked about apps that gamify your workout, especially those whimsical motivators like Zombies, Run! which will have you literally running for your life. But for those of you who prefer a more leisurely pace, you might be a fan of Fitbit or a smartphone that counts the number of steps you take in a day. Everybody has something like that.

And you’ve probably heard fitness experts say that 10,000 steps should be your goal if you want to reap the daily benefits of exercise. 10,000 steps, that’s about five miles a day. Well, did you ever wonder where that number comes from? Of course, it must be backed up by scientific evidence, right? Well, actually, there isn’t a ton of evidence to suggest that 10,000 steps is the sort of magic number that experts claim it is.

So is it more myth than science? And that’s just not true for walking. All of you people standing, got your stand up desk, you converts out there. You’ve got a stand up desk. Sorry, but the jury is still out on that one too.

So what is the scientific evidence behind these fitness claims? You may not believe the hype, but you can trust my next guests. Euan Ashley is an Associate Professor of Cardiovascular Medicine and Genetics at Stanford University, who worked with Apple on their fitness apps. And Bethany Barone Gibbs is Assistant Professor of Health and Physical Activity at the University of Pittsburgh, who is very interested in researching that standing desk. Welcome, both of you, to Science Friday.

EUAN ASHLEY: Well, thanks for having us.

IRA FLATOW: You’re welcome. You and your lab at Stanford is focusing on genomics in medicine. But you do a lot of fitness research as well. What is the connection there?

EUAN ASHLEY: Well, I think that we think about your predisposition to disease a lot of the time in terms of genomics. But what we mustn’t forget is that the environment is really important too, and you have control of your behavior. Genomics doesn’t pre-determine your fate. You have control over your fate. And the best way to do that is to think about your lifestyle and what you do on a daily basis, what you eat, how you act.

IRA FLATOW: Let’s talk about that lifestyle. Let’s jump right into this 10,000 steps a day. A lot of science behind that?

EUAN ASHLEY: Not really. I think we’re often asked about that. It’s something that comes up a lot when people have Fitbit. You mentioned in the intro. Apple Watches are counting steps. And looking at them, they say, well, where did this come from? And really, it was just made up once.

In fact, it was made up in Japan in the 1960s. There was a pedometer that became very popular there. Its nickname was manpo-kei, which means literally means 10,000 steps. And from there, the Japanese health ministry took it on. And it became almost like a meme. It had a life of its own. And maybe because it’s a round number, something that people can understand, or an achievable goal, it became something that just became very popular.

IRA FLATOW: So is anybody testing it now?

EUAN ASHLEY: Well, there are a few. Certainly thinking about steps and physical activity is something that a number of groups are interested in. Our own group at Stanford we, as you mentioned again in the intro, we have been working with Apple and with others thinking about physical activity. We have an app called MyHeart Counts.

And it’s downed a lot of bullets. There’s actually a research study that anybody, almost anyone the world, certainly in the US, can join in. And if you consent to take part in the study, it will upload the number of steps that the phone thinks that you do into the cloud, allow us to analyze it along with the rest of the population, and we can study exactly what effect of exactly how many steps are on your happiness, on your fitness, and other things.

IRA FLATOW: Bethany, your area of study, as I mentioned, is the standing desk, which a lot of people are using, including a lot of folks at Science Friday. Where did the idea of the standing desk, quote, “being good for us,” unquote, come from?

BETHANY BARONE GIBBS: Yeah. Well, first of all, when we think about sitting, the way we sit today is really a new phenomenon. With computers and video streaming, we sit for hours on end, sometimes without getting up. So we haven’t been doing that for very long. And evidence over the past decade or so has just started to accumulate that that kind of prolonged sitting is bad for us.

So in theory, it makes sense if we replace some of that sitting with standing up, it would be better. But we actually don’t really know that right now. The research is just developing, because these sit stand desks just started coming on the market.

IRA FLATOW: So it’s just normally assumed that if you’re standing up, you’re going to be in better shape?

BETHANY BARONE GIBBS: Sure. Well, we have some evidence now, sort of. If you look at people who sit a lot and people who don’t sit very much, the people who sit a lot have more cardiovascular disease, more type 2 diabetes, they weigh more, they have more pain, they’re more likely to die early. But we don’t have that really good evidence, randomized clinical trials, that show us if we change that sitting into a standard behavior, that that is going to improve our health outcomes.

Now, people are doing that research now. We’re really interested in it. But we don’t have the proof yet. So I’m looking forward to that developing over the next five to 10 years.

IRA FLATOW: Let me ask both of you. Do we do we have any idea whether if you’re standing up that makes you pace a little more, or walk around a little more, get a lot more exercise? I know I’m a big pacer. When I have to think something, I’m up and down the hall in the office. What do you think?

EUAN ASHLEY: Yeah, well certainly, there’s a study I was looking at recently, earlier in the week, that showed that fidgeting can be helpful for reducing the chances of clots in your leg, which would be a potentially important thing. We know from some past health studies that fidgeting can certainly increase your oxygen consumption a little, which can definitely help.

In the study I mentioned earlier that we did, actually, we found that there was an association with the number of transitions that you did. So if you were someone who tended to get up, and sit down, and pace around a lot, the association was with less cardiovascular disease. And as Bethany said, I think, that doesn’t mean that there’s a causal effect. We have to go do the study to test that. But there certainly seems to be an association.

BETHANY BARONE GIBBS: In our research, we’re doing some where we just install sit stand desks. And we just measure what people are doing with the best measures we have out there that can really measure position and movement very well. And we find that people, if you install a sit stand desk with people that are interested in it, they stand up a lot, a hours a day. But the extra movement, although we do see a little bit, it’s not very much.

Some recent data we had showed maybe about 12 extra minutes a day. So not necessarily just installing the sit stand desk is going to make you much more mobile. But certainly, you’re up and standing. And maybe you would be more likely.

IRA FLATOW: Speaking of anecdotal evidence about this, we’ve heard over the years all the time, people who have standing jobs, waiters, waitresses, they’re on assembly lines, doctors– their backs are killing them. They wear special shoes. It could be just the opposite. It may not be good for you, too much standing.

BETHANY BARONE GIBBS: That’s a really good point. There’s actually a lot more research out there that’s looking at too much standing. So I think the recommendation, certainly, is not to stand all day. It’s to alternate positions frequently and move around when you can. So I think that standing all day is not good for you. Sitting all day isn’t good for you. We just need to understand better if alternative between those two things is actually going to improve your health.

EUAN ASHLEY: I think moving is really the key thing. And even from the earliest days in the late 40s, when the first studies were done back in the London buses– I don’t know if you’re familiar with that study.

IRA FLATOW: Oh yeah, Big Red.

EUAN ASHLEY: Yeah, so with Jerry Morris, first of all, decided to study the conductors and compare them with the drivers, because they inhabited the same environment. The difference is that conductors went up and down several hundred stairs every day. So they were moving constantly. He found the cardiovascular disease rate was half in the conductor’s compared to the drivers. So this was the very first indication that exercise really was good for you.

IRA FLATOW: So you should be having a Stairmaster that you’re working on.

EUAN ASHLEY: Potentially.

BETHANY BARONE GIBBS: There’s a few studies now that are trying to tease out just standing. Is that going to give you a real health benefit? And the thing is that although, yes, moving is great in our current American office culture, if you stand at your desk, you can still be working. And that’s valued. And if you have to walk away, you’re not necessarily still working. So there is real interest in understanding whether just standing is of a health benefit.

We did some work looking at, really, how many extra calories does it burn to just stand up. We recently published that. And it’s not a lot. If you alternate 30 minutes up, 30 minutes down, maybe you’re going to burn an extra five or six calories an hour. Over a day, that’s going to be 40 or 50 calories, which is not a ton. But it could build up. And it’s just one small change that you can easily make that could contribute to preventing weight gain.

IRA FLATOW: What about– I’ve seen now, these little, tiny treadmills. I’ve seen some receptionists walking very slowly. You know about that, Euan?

EUAN ASHLEY: Yeah, I think that as we said, the standing desk is the first thing. Stand up. But perhaps, if the idea is to keep moving, then maybe a little treadmill desk that can go under your desk. Because as we were saying, it’s hard to work if you’re walking around. Although you can have walking meetings, we encourage that where we are.

IRA FLATOW: Wait a minute, a walking meeting? How does that work?

EUAN ASHLEY: Well, you just take the person who walked into your office, and say, do you want to go walk outside? It’s a little easier in California than some other parts of the world. But it’s certainly a good way. We have a beautiful campus at Stanford. So walking people around it is good.

IRA FLATOW: That’s how Einstein used to say. I’m going to give a little think. I’m taking a walk while I think about it.

EUAN ASHLEY: Well, it gives you a little break too, gets you into the outdoors, a little bit of air. Plus exercise, maybe you’re saving your life. My favorite fact, actually, about this is that– and it’s driven from a study of 500,000 people, so the data behind it is pretty good. But that if you exercise for one minute, you get five minutes of extra life. And that’s how powerful exercise can be.

IRA FLATOW: Is that something like interval training?

EUAN ASHLEY: Doesn’t have to be. In fact, if you take higher intensity exercise and map it with that same equation, it gives you a few minutes more than five minutes of extra life. So the idea that I don’t have time to exercise, this is when I talk to my patients, I’m always saying– you have time to exercise, because every minute you exercise you get five minutes more of extra life.

IRA FLATOW: Do you have plans to tackle any more fitness myths along the way?

EUAN ASHLEY: Well, certainly I think, again, a very good point made is that we haven’t tested a lot of these. A lot of them come from observational evidence. They’re very rational. They make perfect sense, the idea.

IRA FLATOW: And they get very accepted so widely. How come they’re accepted so widely without the evidence?

EUAN ASHLEY: I think sometimes it’s a round number. 10,000 is a good, round number. It was very reasonable. The current American Heart Association and the American College of Sports Medicine recommendations are to exercise for 30 minutes, five times a week. And if you add that to about 3,000, 4,000 steps to your sedentary steps, it takes you to 8,000 or 9,000. So it’s very reasonable.

It just hasn’t been tested. It’s not that we did 6, 8, 10, 12, 14. And said, OK, 10 is the right number.

IRA FLATOW: Because I feel so defeated when I’m only up to 8,000 instead of 10,000. But no one knows if that’s the real number. So I may be OK.

EUAN ASHLEY: You may be OK. We don’t want you to feel defeated. We want you to do more than you were doing before, because more definitely is better. But we don’t want you to feel depressed and do less because you hit 8,500 rather than 9,000 or 10,000.

IRA FLATOW: And Bethany for you, what are you most looking forward to studying next?

BETHANY BARONE GIBBS: Well, I’m really excited to see the results of the randomized clinical trials going on and being proposed that are going to experimentally alter sedentary behavior in populations that have a lot of prolonged sedentary behavior, so people working in offices, older people that are living in managed care, and kids in schools. There is actually an awesome study that came out of Texas A&M last month.

They installed some stand bias desks, so these are high top desks with a high stool. So they promote standing. They installed it in half the classrooms and followed kids for two years. And kids that were in the stand bias desks actually gained 5% less in BMI percentile points over the two years. So this is definitely a modest effect. But it’s still exciting because when we think about the obesity epidemic and how we need to help kids and all people not gain weight, this is a real strategy that could be implemented on an environmental level.

IRA FLATOW: Of course, none of this really would be possible if we didn’t have all this new technology to share. First, measuring your own activity and sharing.

EUAN ASHLEY: I think that the technology is really helpful. Again, the jury’s out on exactly how we should use it. But that feedback has got to be an important part of it. And I think also, speaking to Bethany’s point, I think the observational data is good and should give us the hypotheses that we should test. But testing them becomes really important, because that’s the only way we really get to causality.

And so we’re excited, for example, about the next phase of our study where we can use the technology to actually do randomization.

IRA FLATOW: I’m Ira Flatow. And this is Science Friday from PRI, Public Radio International, here talking about fitness and some of the mythology about it. In your lab work, as you mentioned, you worked with Apple when it was putting together its fitness apps for the new iPhone. How did that get started? Did they seek you? Did you go to them?

EUAN ASHLEY: It’s actually an interesting story. So every year at Stanford, we run a conference called Big Data in Biomedicine, the idea that now we’re measuring so many more things that we need to think about how we apply them to patient care. And so I just finished a talk there and came off the stage. And I was approached by a couple of people who came up, and in rather hushed voices, said, we can’t tell you who we are or what we do. But we want to work with you.

IRA FLATOW: Mr. Phelps.

EUAN ASHLEY: And so, well, we thought was this the FBI or the CIA? Or what exactly was this? Well, it turned out it was Apple. They are so secretive about what they do, in a good way. They like to surprise their customers with new things. They keep everything quiet until the last minute. And this was the beginning of a very, very interesting year-long relationship where we put together these initial launch apps.

IRA FLATOW: Let me ask both of you in the few minutes we have left. What do you think about the driverless car? How is that going? Bethany, I ask you then Euan. How is that going to affect our fitness?

BETHANY BARONE GIBBS: Well, I hadn’t really thought about it too much with fitness. I’ve thought about it a lot how it could help me get more work done. But I think, we in the world of physical activity promotion, are trying to get people out of cars, and trying to get people to do more active transportation. So we want people to walk to public transportation. It’s also environmentally friendly. So if they become very cost effective and more people get on the road, and there’s less accidents, potentially people will be sitting even more. So I guess we’ll have to design driverless cars that have a bike in them or something so that we can exercise at the same time.

EUAN ASHLEY: Yeah, my team are going to think that I asked you to plant that question, because I’m obsessed with driverless cars.

IRA FLATOW: Oh, you are?

EUAN ASHLEY: Yes, I am.

IRA FLATOW: Well, then weigh in on this.

EUAN ASHLEY: A little sideline of mine– I love technology of all kinds. So I think that, obviously we’re all thinking about if the car could take us from A to B, we can get other things done. And other things, of course, could include work, could include talking to our families more, could include being creative, composing. In time, who knows? It could potentially include exercising as well.

I think we spend so much time in cars right now that if the technology can allow us to be more efficient in any part of our day, then we could spend that spare time doing exercise.

IRA FLATOW: Is there a bit of technology– I can give you a blank check question, a blank check to write and buy some or make some technology for fitness to measure it, to use it. What would you do? What are we missing? Is there an ingredient, a technological ingredient?

EUAN ASHLEY: Well, I would love to be able to measure the actual output from somebody’s heart. We’re very good at measuring the heart rate. And we are increasingly good at trying to measure the heart rhythm. But really, when it comes down to it as a cardiologist, I’m really interested in how much blood can the heart pump or beat?

IRA FLATOW: You guys call it the volume.

EUAN ASHLEY: That’s correct, the stroke volume, with every beat. Because then I can tell you how much work your heart’s doing when you’re walking, when you’re running, when you’re jogging, how much you did all day yesterday. And if your heart starts to fail, as we hope it does not, but if it did, that would give us an online way of monitoring your heart and our treatment of it.

IRA FLATOW: And you can’t do that now?

EUAN ASHLEY: We cannot. It’s very, very hard to do that noninvasively. Give me a catheter to stick inside your heart. I can tell you.

IRA FLATOW: Well, there was those folks who were on before talking about reading the scrolls when they were closed. Maybe they can read the volume. Why can’t you read the volume?

EUAN ASHLEY: I would love to be able to do that. So if you write me a blank check, I promise I’ll get that.

IRA FLATOW: OK, don’t wait too long for that check. I thank both of you. Euan Ashley, Associate Professor of Cardiovascular Medicine and Genetics at Stanford, and Bethany Barone Gibbs, Assistant Professor. I’ve just elevated you, Bethany, of Health and Physical Activity at the University of Pittsburgh. Thank you both for taking time to be with us today.

EUAN ASHLEY: Thank you very much.

BETHANY BARONE GIBBS: Thank you.

IRA FLATOW: You’re welcome.

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