Live Long and Well with Dr. Bobby

Episode 11: Try to sit less and move more

Dr. Bobby Dubois Season 1 Episode 11

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Key Takeaways

  1. Sit Less, Move More: The evidence is clear—reducing sitting time and increasing movement are crucial for health.
  2. Exercise Isn't a Substitute for Moving: While exercise is beneficial, sitting has its own distinct risks that need addressing.
  3. Practical Tips: Even small changes, like standing up regularly, can make a significant difference in your health.

Understanding Movement and Steps

Daily steps vary significantly by age, gender, and location. While the ideal number of steps isn't clear-cut, communities with higher step counts, like the Blue Zones, offer insights.

The Impact of Sitting

Ten years ago, Americans sat for perhaps 8 hours per day and that may be much higher post COVID.  Sitting time varies by country.  You can estimate your sitting time here.

Studies show that those who sit more have much higher mortality (34% higher in those who sit 10 hours/day vs. those sitting < 1 hour/day).  Although exercise has many benefits, it does not fully undue the harmful effects of prolonged sitting. Being sedentary also appears to raise cancer risk. 

Blood vessel changes have been shown after 2 hours of sitting.  We don't know the "safe" amount of sitting--my interpretation of the evidence suggests perhaps 10 hours raises the risk substantially, <3 may be ideal, and perhaps 6 hours/day may be a good target.  

Practical Strategies to Reduce Sitting

Studies have shown promising results with interventions like standing desks, fitness trackers, and gamified challenges to encourage movement. Even small changes in daily routines can lead to measurable health benefits.  And, exercise can reduce existing heart abnormalities.   Try to stand regularly (perhaps every 30'), have walking "meetings", or use a phone/watch app to remind you.




Bobby Dubois:

Hi, I'm Dr Bobby Dub ois and welcome to Live Long and Well a podcast where we will talk about what you can do to live as long as possible and with as much energy and vigor that you wish. Together, we will explore what practical and evidence-supported steps you can take. Come join me on this very important journey and I hope that you feel empowered along the way. I'm a physician, ironman, triathlete and have published several hundred scientific studies. I'm honored to be your guide. Published several hundred scientific studies. I'm honored to be your guide.

Bobby Dubois:

Welcome everyone to episode 11, where we will talk about trying to sit less and move more. Turns out this is a really important topic and one which can affect how long we live and how well we live Before we get going. I wanted to share with you today that it is my birthday Now. I'm sharing this not because I want nice comments although of course, that's always lovely but last episode I said that I would share more about myself and why what we talk about is so important for everyone and also important to me as well. Today I turned 68. Now I feel blessed to have good health and that I can still train for my next Ironman triathlon in October, and I finished a shorter version race over Memorial Day. These events typically range from four to 16 hours, depending upon the distances, and I've done and have been blessed to do four full-distance Ironman events and about a dozen half Ironman races, all in the last 15 years or so. I guess what I want to say is that a large part of my success has been the six pillars we talk about. Not only do scientific studies support our discussions, my personal experiences help me to believe it as well.

Bobby Dubois:

Now, many of you in your 30s and 40s. The point I'd like to suggest is to be active in your 60s. You need to start when you're younger and have the pillars as a lifelong part of what you do. Waiting into your late 50s or beyond is better than nothing, of course, but it's best to start as soon as you can, and I hope you will take this to heart Now. My true hope is that you can all be active and feel as I do when you reach this age. We'll talk about this more in future episodes, but I do believe my success in life, including being a physician and a scientist, having published 180 papers or so peer-reviewed publications has helped from my ability to see how much can be achieved with as little effort as possible. Now I don't know if it's my secret sauce, but I hope to share with you how you can get a lot of benefit from making relatively small changes. It's worked in my life and I hope to help you do the same. Well, enough about me.

Bobby Dubois:

You might wonder where did the topic of sitting come from? Well, for the past few months, I've been running across scientific studies that show how being sedentary or sitting can affect our health. Now, for a while I ignored the studies, since I assumed that, since I exercise almost daily and I work outdoors on our ranch and bed and breakfast, that all is well, that I'm doing enough. Then I got this nagging sense that perhaps I was missing something. So I dug into the studies more carefully and found that, although exercise is wonderful, it doesn't fully protect us from the harms of sitting. Now this led to a dilemma Is sitting just what you do if you're not exercising, or is there something different, unique, about sitting that's worth understanding? Having spent perhaps way too much time reading scientific studies on sitting and being sedentary sitting and being sedentary I wanted to share what I learned from them and provide you with some very tangible and practical steps you might consider. Now, as always, show notes will have links to the studies and if you wish to provide feedback which I love or raise questions, which I especially love, you can do so on my website or Instagram, which is drbobbylivelongandwell.

Bobby Dubois:

Well, as always, we'll begin with some take-home messages, and there are three of them. First, let's all try to sit less and move more. There's ample evidence to motivate us and we'll walk through it and hopefully you'll be as convinced as I am by the end of the podcast. Message two exercise is great, but that doesn't mean sitting is okay. Surprising to me, and this was not what I anticipate they are separate things to consider and both things have to be addressed, both exercise and minimizing sitting. Third, the good news there are practical tips to help you, and even small changes matter. Now, it may be hard to get a full exercise program going or do a daily meditation exercise, but standing up periodically may be really doable for you and that's the exciting part. You can make a large set of changes with real benefit, and it may not be as difficult as you might think.

Bobby Dubois:

Well, let's lay out the plan for the episode First, part one. We're going to define terms or set the stage. There's lots of activities and we want to narrow it onto the ones we care about, but we'll mention all types of movement vigorous exercise, moderate exercise, walking, sitting and then, of course, sleeping. Next part well, what are the health consequences of being sedentary and specifically related to sitting? Part three what has been shown to work in people to reduce those risks. And, fourth part of the episode, I want to translate the results of the studies into practical steps you can take.

Bobby Dubois:

Well, part one, some background to get us started. Well, in episodes one and two we talked about how, ideally from an exercise standpoint, we want to get at least 150 to 300 minutes per week of aerobic exercise, or what's called moderate to vigorous exercise, which means you're exercising and you can talk. You're not so short of breath, you can't talk, but it's not so easy to speak in full sentences. Speak in full sentences. Only 10 to 15% of Americans get 30 minutes of moderate to vigorous exercise per day. It's a difficult bar for people to surmount, but it is one that has real benefits that we've talked about.

Bobby Dubois:

Now here is a nerdy tidbit which maybe only nerds like me will enjoy. If you look at the scientific literature on movement, and this is what I did for the last period of time. You'll find lots of surveys of people or studies, and in the you know 2000, 2005, 2010,. You know 1990,. The way you would do a study like that is you would either ask people how much they walk around or sit, or you'd ask them to wear a pedometer, which is this old fashioned thing you would attach to your belt and it would show you how many steps you did. Now, people didn't normally wear pedometers, but if it was part of a study, you would, and the problem is, since you didn't normally wear a pedometer, once they put one on you, you were probably more aware of how many steps you took, and you might have taken even more than you otherwise would. So you've kind of changed the experiment when you attached a pedometer to somebody.

Bobby Dubois:

Well, let's fast forward a couple of decades. Now. These studies are based upon smartphone or smartwatch data, so you're not being asked to do something different. You're carrying your phone around all day long or you have your watch on all day long and all that's happening in the study is that information is being uploaded to the research center and they're counting steps. So the ones that we do today likely are much more accurate, because people don't really think about the fact that their phone is capturing their steps and they tend to ignore it. All right back to the less nerdy stuff.

Bobby Dubois:

Well, I mentioned about steps, so let's sort of dive in a little bit about steps. Now, steps isn't the same as sitting, but obviously, if you're walking around, you're not sitting, but we're moving in the direction of the data, the evidence, the studies on sitting. So aerobic exercise you're moving enough that you're getting a bit short of breath. So now let's look at steps each day. Well, these studies have been going on for a few decades and, as we'll come to in just a bit, I believe that the studies that were done in 2005, 2010, 2015, and up until COVID numbers may be higher than they are actually today. So, in a study in 2003, looking at 1,100 adults, the average number of steps was about 5,100 steps per day. Interestingly, in that study, women took about 500 fewer steps per day. They didn't really explain why. That's just what they found.

Bobby Dubois:

Now, the number of steps, how much people walk, varies a lot from country to country, and this was based upon some smartphone data in 2017 from about 700,000 people. So it's a lot of people from lots of countries around the world. In the US there was about 4,800 steps per day, in the UK it was about, say, 5,500 steps and in Japan it was 6,000. Also of interest is that the number of steps per day is the most when we're in our 20s. Actually, it's not as high when we're an adolescent, because we're sitting down at a desk at school most of the day. And as we get a bit older the number of steps typically at least in this study fell. So by ages 40 to 50, that number had fallen by 15 or 20 percent. Had fallen by 15 or 20 percent Now.

Bobby Dubois:

As I alluded to, all these studies were done pre-COVID and before there was this massive shift to remote work. I couldn't find a lot of recent survey data on number of steps post-COVID, but I suspect it's fallen. Well, how many steps a day is the right amount? And the short answer is we really don't know. If we look at the blue zones, these are these communities around the globe like Sardinia, loma Linda, california, okinawa the average number of steps per day was about 10,000 or perhaps twice what we get in the US and these blue zones. Not everybody lives to be 100, but a lot more people live to be 100 than in other communities and when they were studied people tried to figure out what do they do differently. So one of the things it appears is they walk a lot more.

Bobby Dubois:

Now one of the blue zone areas is the Amish and the Amish, as you may know, kind of live in a pre-technology era. Kind of late 1800s is kind of the circa, when they sort of stopped adopting new technology. And this study where they asked some Amish adults to wear a pedometer, they got about 18,000 steps in men and about 14,000 in women, so even more than the average blue zone and three times probably what most Americans get. And, as is important, not only does the number of steps vary, but the number of steps is related to mortality, not just heart disease mortality but overall mortality. In a meta-analysis where they combined information from about 12 studies, they used 2,000 steps as the baseline.

Bobby Dubois:

Now, not that a lot of people only get 2,000 steps, but that was kind of their starting point. And then they asked the question well, if you walk 2,500 steps, how much benefit? If you walked 2,700 steps, how much benefit? And what they found is that when you went from 2,000 steps to 2,800 steps, you dropped your mortality by 8% relative to that 2,000 steps. And if you increase it just a bit more to over 2,700, a bit more, then you dropped it by 11%. And they did a lot of kind of calculations to figure out what optimal was and it appeared to be about 8,700 steps and for those people they fully dropped their mortality rate by 40%. So gives us an inkling about maybe how many steps would be a good target. If you want to use the blue zone targets about 10,000. If you want to use this study, it's about 8,700, and probably 4,000, 3,000 or less is not a good number. Well, as we know, today's episode is not really about walking or aerobic exercise, but it's a good place to begin.

Bobby Dubois:

So now let's talk about sitting. And what do we know about sitting? Well, there's many studies in this arena, which surprised me, because when I dug in I had no idea there were as many studies as there were. But let me sort of sitting a day in adolescents, a bit less in adults.

Bobby Dubois:

In another study this was in another country office workers. So while they were at the office during a workday, which is presumably about eight hours, these workers were sitting about 6.3 hours. So most of the time when they were at work they were sitting. Now, obviously these were office workers, probably at computers and the like, but 6.3 isn't the total amount of sitting, because they obviously had to get to their job and home. That could be another hour or more, and then when people get home at the end of the day they're sitting down and eating for their meals. That's more time sitting than people after dinner may watch a couple of hours of TV or read a book, and you could easily be at nine or 10 hours of sitting for a typical person. So that's an interesting number to keep in mind. Well, just like the number of steps, the number of hours sitting varies by country. So in Portugal and Brazil and Colombia, they sit for less than three hours a day on average, whereas in Taiwan, norway, it was about six hours a day.

Bobby Dubois:

Here's an interesting tidbit that people who had higher education had 35% more sitting time than people who didn't have higher education. Now, this probably isn't a surprise, because if you had higher education, you're a lawyer, you're a software person, you're likely to be having a seated job, whereas somebody with less education might be working in a retail store on their feet all day long, or they might be in a factory or work in a grocery store or something like that, or they may be, you know, a plumber or something where they're again not sitting very much. Now, as I mentioned, I believe whatever sitting numbers we've looked at pre-COVID may be worse today. Now I did find a study that was done in 2000 or published in 2024. And this was done in the Netherlands, and they found that the average sitting time was 9.4 hours. Now they also tried to figure out, well, what is the optimal number of hours to be sitting, and probably the real answer is the fewer the better. But when they looked at how much people sat and what their waist circumference was you know what their waistline was and whether they had any evidence of sort of pre-diabetic blood test results, they kind of triang of the tribe, of sort of indigenous individuals called the Hansa, and they live in Africa, in northern Tanzania. What's very interesting is they have almost no heart disease but they're sedentary 10 hours a day. Now, we're going to return to this later, but it may turn out that although they are sedentary, it may be quite different than the way we are sedentary. Okay, so we don't have the exact number of sitting hours. That's optimal. It could be three hours, it could be six hours, it's probably not eight or ten hours, as we're going to talk about very soon.

Bobby Dubois:

Well, where do you fit on this? There is a website called standorg, and they have a calculator that will help you estimate the amount of time sitting. Estimate the amount of time sitting. Now, this isn't based on a smartwatch or a phone or anything scientific from a measurement standpoint, but it'll walk you through various activities you do during the day and it might give you an inkling of how much time you are spending sitting. Just so you're aware. I don't know anything really about the standorg, but they were started by a company called Ergotron, which makes standing desks, and of course, they want you to stand more. So I don't think the calculator is in error, but just so you're aware, from a full transparency standpoint, that when you look at it, it may be a company that's encouraging people to sit less and stand more.

Bobby Dubois:

Well, as you begin to try to quantify how many hours you might be sitting during the day, it is going to vary. I mean, if you drive Uber for a living, you're going to be sitting a lot. If you sell clothes in a retail store and you're on your feet working with customers and showing them apparel. Obviously you're not sitting down very often. Are you a classroom teacher, where you're kind of up and down a lot? Or, like many of us, are you at a computer, a computer-based job, and you know it may be an eight-hour-a-day job but, as we know with sort of remote work, you're often at your desk even more than that. So then of course, if you've got a job that you commute to, then you got to add in that time, and then the seed for meals, and if you watch TV, it could easily amount to 10 or 12 hours of sitting. Obviously it's not 12 hours in a row, but over the course of the day it might turn out to be 12 hours of sitting.

Bobby Dubois:

All right, we've given some background about sitting, but now we got to get to the meat of the issue, which is really the harm associated. Now I'm not going to talk too much about some of the harms of sitting that you may know about already, like if you're on a long airplane ride, you might worry about blood clots, or if you broke a leg and you're stuck in bed, you could also at risk for blood clots, and if you're sitting a lot, you're not exercising and your muscles might not be used, and that could create problems. But I want to focus really on what are the long-term effects on how long we might live and, of course, how well we might live, on how long we might live and, of course, how well we might live. So there was a study of studies, what we call a meta-analysis, and there were six studies analyzed in about 600,000 adults, and what they found is, when they compared people that were sitting for 10 hours a day and again, many of us may be in that zone compared to people who sat very, very little, they had a 34% higher mortality from the sitting. Now, okay, that sounds interesting, maybe even scary, but do we think this is true? Well, there's a few things that suggest this might actually be accurate. The first is and we've talked about this before it's called the dose-response relationship. Well, if a little sitting isn't so bad, but a little more sitting is a little bit worse and a little more sitting beyond that is even worse. That strengthens the observation. And what they found in this study is that for each hour of additional sitting, there was a 2% to 3% higher mortality rate. You know, if it's an extra five hours or seven hours. You can do the math and see where you're at Now.

Bobby Dubois:

The other thing they found and this to me was an eye-opener is that when they took into account not just how many minutes you were sitting a day, but your physical activity when you weren't sitting, it didn't eliminate the problem. So my belief that I was exercising every day, therefore I can go and relax and sit, turned out not to be the case. Now, it wasn't that the exercise didn't help at all. It did, but it didn't eliminate the risk of sitting, and that's why it was my wake-up call that there is something uniquely problematic about a lot of sitting. Before we get to a conclusion, like we know the answer, I want to point out these are observational studies. They didn't randomize Some people.

Bobby Dubois:

You know you're going to sit for seven hours a day and you're going to sit for 10 hours a day and see what happens. You're going to sit for seven hours a day and you're going to sit for 10 hours a day and see what happens. The people who sat more it's possible they had other medical issues that caused them to sit and then also caused them not to do so well, but I kind of think it's real because it's been repeated over and over and over again, analyzed a million different ways. So I do really think there is something about walking and taking a lot of steps and there is also something also about sitting and too much sitting. In a related study they looked at TV watching, because obviously when you're watching TV, you're sitting. For every two-hour increase in TV watching, there was a 13% increase in mortality. Again, it kind of dovetails to what we talked about about for each hour or so of sitting, you might end up with 3% or 5% more increase in mortality.

Bobby Dubois:

Well, there's also been studies that show that sitting, being sedentary, is associated with cancer and that for colon cancer, being very sedentary might increase your risk of colon cancer 30 to 40 percent, breast cancer maybe by 8 to 15 percent and endometrial cancer maybe 30%. So there may be a strong relationship between being sedentary and cancer as well. Well, some public health folks said well, what if we reduced how much our entire population sat? How much benefit might we find? And what they found was that almost 7% of all deaths they projected might be related to being sedentary. And if we could get ourselves to be a bit less sedentary, that was a huge number of people. And again, in this same study, they found, compared to people who sat for less than four hours a day, that if you sat for 11 hours, you had a 40% higher risk of death, and if you sat for maybe oh, four to eight hours a day, it was about a 15% increase in death. So, and again, once again, 15% increase in death. So, and again, once again, this study accounted for physical activity.

Bobby Dubois:

So exercise is good, but sitting a lot is a problem as well. Well, it would be great if we could come up with the perfect number. So what is the right amount of sitting? I don't think we know. It may turn out just like exercise more is better, sitting less is better. A number of studies, some of which I've already alluded to, point to maybe six hours or so, where above that, it gets to be much bigger of a problem. It might turn out it's really three hours of sitting is better. But what we do know is probably, when you're getting in the eight to 10 hour per day amount of sitting, that could be a problem.

Bobby Dubois:

Now I want to point out that sitting has nothing to do with sleeping. Sleeping is a different category and that's not included in the eight to 10 hours a day. Well, the data, as I said, was observational data and it's compelling. But why might this occur? I mean, we need to have kind of a theory here. Well, there was a study that was done that asked people to sit for two hours and they were not allowed to move, just sit for two hours. And what they found is at the end of the two hours and these were healthy people their blood pressure rose by almost three millimeters and the compliance in their arteries, meaning how flexible their arteries were, went down. Now it probably got better once they got up and moving around, but it suggests that there are cardiac changes that happen within a couple of hours of sitting. And then, if this is repeated over and over and over, day in, day out, you can begin to see that it isn't just a theory that sitting can be problematic, that you could actually kind of figure out why and how.

Bobby Dubois:

Well, I didn't give you the punchline about the Hansa tribe from northern Tanzania. Well, they do find that they are sedentary 10 hours a day, but when they are sedentary they're not sitting in a chair, they're squatting or they're sitting on the ground. So they're using core muscles. They're using their muscles as opposed to us. When we're sitting, we're sitting in a chair which is supporting our back, is supporting our legs, and we're really not doing very much. So the 10 hours a day of them being sedentary is really different than the 10 hours we do. Okay, I've made an argument that sitting is an issue to pay attention of and that it can cause problems. So part three of our discussion is how do we minimize the problem?

Bobby Dubois:

Well, there was a randomized trial where they took people and said okay, we're going to work with you to reduce how much you sit. And these were people in their late 60s and a bunch of them had high blood pressure. So what they did is they took half the people and they said okay, we're going to provide some coaching, we're going to set goals for sitting, we're going to give you a standing desk, we're going to give you a fitness tracker that will kind of prompt you to stand up and walk around. And what they found was that it was a success. They found that there was 31% not 30, I'm sorry 31 minutes less sitting time per day, and their blood pressure went down. So that's a good one.

Bobby Dubois:

There was a similar study that was done in office workers and these are folks that basically were sitting down at work and they created a game. So they gave them a Fitbit you know the thing you wear and they gamified it, as it were. So what they did was they would send them text messages throughout the day, they would put them into teams and they created a game of who on your team would take the most steps and you would compete against other teams. So it made it kind of a fun thing to be aware of how many steps you did a day. And they found real improvements 2,000 steps a day more in people who were having the Fitbit with the game. Unfortunately, this type of intervention kind of loses power after a while and after about nine weeks of doing this, half of the benefits had already fallen. Well, there's also been examination of Fitbit in people who are overweight and they randomized them and some of them got the Fitbit, which you know, then talked to your phone and showed you how you're doing. So kind of immediate feedback versus some other people who just got the simple pedometer. That didn't tell them too much but that also worked.

Bobby Dubois:

And here's another study. It's not about sitting per se, but what it tells us is that good movement behavior can improve our heart. So they took 53 people who were sedentary and they were in their 50s and they randomized them. Some of them had an exercise training program for two years and the others didn't. And then they did some extensive studies of their heart and what they found was the heart improved, it was less stiff, more blood was being pumped out, and what that suggests is that, even though these were people in their 50s and had perhaps damage to their heart, it could be improved by moving more. Well, let's now go to part four, which is practical things that we can do Now. This is not based upon any particular study. It's sort of an amalgamation of all these studies and some thinking I've done and what others have said.

Bobby Dubois:

Well, if you're at a desk job and you're sitting a lot, try to get up and walk around a little bit every 30 minutes. Is that a magic number? Well, we know that two hours created problems in the blood vessels in your legs, but we don't know. Is one hour okay? Is it every 30 minutes, every 15 minutes? But I don't know. But regularly getting up and walking about for a little bit is a good idea, but regularly. Getting up and walking about for a little bit is a good idea.

Bobby Dubois:

If you're stuck sitting, move your muscles and stretch a little bit and try to stand for just a moment. That's something you can do. If you have access to a standing desk or a sit and stand desk, you could raise it or lower it. That can really help how much you sit. Think about when you have a meeting or you get coffee with friends. Try to do it walking instead of sitting. If you're in a work situation and you're thinking of sending an email to your colleague down the hall, maybe get up out of the chair and walk down the hall is another way to reduce your sitting. And there are apps. There are apps on your phone, there's apps on your watch that can remind you regularly to stand up and walk around. I'm also told that on Outlook, if that's your kind of way of managing email and such in the task function, you can have it pop up every 15 or 30 minutes to stand up and take a stretch break. You can then turn off that reminder and then, 15 or 30 minutes later, it may pop back up again.

Bobby Dubois:

All right, let's conclude. Sitting is worth thinking about and worth doing something about. Try, if you can, to do a self-assessment and get a sense of how much you sit. Exercise is great. We're going to continue to talk about the benefits of exercise. Walking is wonderful We'll continue to talk about that. But be aware of how much we sit, because that turns out to also be important. Start slow. You don't have to do this to perfection. Try getting up each hour, whatever works for you, to start to make changes in what you do and how you do it. Perhaps add an app to your phone or something on your Outlook on your desktop.

Bobby Dubois:

Now, as everyone knows, I love end-of-one studies where we assess our baseline. We might do something to reduce sitting and then see what happens. The problem is there really isn't something you can measure to say you know, I reduced my sitting by two hours and look what benefit there was. Unfortunately, there's no simple thing to measure. What we have to do is look at the studies and say it's pretty compelling, so I guess I better do it.

Bobby Dubois:

But we can't do our N of 1 study Unless one of you can come up with what you might measure in the short term. That would be easy to measure for everyone and then I would be very happy to share. So that is the end of our episode. So until next time, I hope that you live long and well and I also hope you will continue with me on this journey so long for now. Thanks so much for listening to Live Long and Well with Dr Bobby. If you want to continue this journey or want to receive my newsletter on practical and scientific ways to improve your health and longevity, please visit me at drbobbylivelongandwellcom. That's drbobbyivelongandwellcom.