Audio Transcript:
Hi, I'm doctor Mike Evans and welcome to this visual lecture I'm calling 23 & 1/2 hours.
So I have a big interest in preventive medicine, you know, which can mean a lot of things from cancer screening to eating more fibre, to having a good social network and I mean this in the old sense of the word, weight loss, drinking less, smoking less, controlling your blood pressure, cholesterol and so on and so forth.
All of this things are incredibly important and I wouldn't want you to minimise your efforts in any one category, but I want to know what comes first, what has the biggest impact, what has the biggest return on investment, what makes the biggest difference to your health.
So I did my research and I found an answer to this for me, and it's tricky because all these things are sort of overlapping, but I picked up this intervention because of its breadth and it worked for so many different health problems, and that's what I found so cool about it. Just to walk you through a quick list.
So this intervention in patients with knee arthritis who received one hour of treatment three times a week reduced their rates of pain and disability by 47%. In older patients it reduced progression to dementia and Alzheimer´s by around 50%. For patients in high risk of diabetes when coupled with other lifestyle interventions, it reduced progression to frank diabetes by 58%. Post-menopausal women who had 4 hours a week of the treatment had a 41% reduction on the risk of hip fracture. It reduced anxiety by 48%. In a big meta analysis in patients suffering from depression, 30% were relieved with a low dose and then bumped up to 47% as we increased the dose.
Following over 10,000 Harvard alumni for over 12 years, those who had the intervention had
23% lower risk of death than those who didn't get the treatment.
It's the number one treatment of fatigue, and of course the outcome of choice, my favourite outcome, is quality of life, which is really all of the above, and really about making you life better. And this treatment has been shown again and again to improve quality of life.
So the question is - what's the medicine? And what is 23 & 1/2 hours?
The medicine was exercise.
Mostly walking, so not triathlons, and let me just put it in a different way; I think what I'm asking you to do is if you think about your typical day there's 24 hours. And so you might spend most of your day, you know, this varies, obviously, but, coach surfing, sitting at work, obviously sleeping. And what the evidence I'm about to show you tells me is the best thing you can do for your health is to spend half an hour being active, maybe an hour, and that if you can do that you can realise all the benefits I described in the previous slides.
So let's take a quick walk through some of the literature…
Steven Blair, He´s a professor at the Arnold School of Public Health at the University of South Carolina, and he looked at this in what is called the Aerobic Centre Longitudinal Study, which followed over 50,000 men and women over time and along the left side of this graph is something called attributable fractions, which is kind of a fancy word but it's the estimate of the number of deaths in a population that would have been avoided if that specific risk factor had been erased, for example turning a smoker into a non-smoker, a couch potato into a daily walker and along the bottom are the typical risk factors. You can see that hypertension is incredibly important, and so on and so forth, but the one that kind of implied the most risk was CRF which is Cardio Respiratory Fitness, which is really low fitness.
So low fitness is the strongest predictor of death.
So this is important, because most of the trials we see are funded by Pharma or other companies because they have a drug for high cholesterol or diabetes, but we rarely see fitness thrown into the mix. So it’s nice to see a trial that is not so siloed.
Blair's work is interesting. They also did another trial looking at obesity, and what they found is that obesity and no exercise - that's a very bad combination - and that´s where we saw many of the negative consequences of obesity from a health point of view. But if the obese person was active, even if they didn’t have the weight loss, but were just active and obese that was much, much better, and the exercise ameliorated many of the negative consequences of obesity.
So if exercise is the medicine, what’s the dose?
And when I think of dose, I mean, how long? How often? And how intense?
I´m going to give you a slightly mixed message, but essentially, more activity is better, but I must say that the rate of return seems to decline after 20 to 30 minutes a day. So if you have been active less than 150 minutes a week or more if you´re a kid, an hour a day if you're a kid might fly by, so my personal take on this is that, you know, the literature draws a very broad brush.
And so we see big differences when somebody goes from not doing anything to doing something, and after that the return is more granular. So if we take the nurse´s health study, women who went from 0 activity to just 1 hour a week reduced their heart disease rates by almost half. So you can break it down so its just 10 minutes, 10 minutes, and 10 minutes if you want to do 30 minutes of exercise if you want it broken into 3.
Higher intensity… It looks like higher intensity is equivalent to less time than lower intensity. But I think the clinical pearl is mostly thinking about your style and habits, and your personal cues. So if you’re only going to do it if its pre-booked, with friends, couples who take a half hour walk every morning, or in the evening to organize their life.
A dog is a great walking coach. The data is showing that 67% of dog walkers achieve 158 minutes a week just with the dog walking.
Following of course, your commute, getting off a stop early, taking the stairs, and so on and so forth.
So, thinking about that, I'm just going to walk you through some quick slices of the literature.
And the first one comes from Japan. In the 90's Japan required all employers to conduct health-screens for their employees. And so a large gas company in Japan called Osaka used this to answer a great question. And so people who walked to work, did that reduce their chance of serious health problems? So, in this example: high blood pressure. And what they found is: under 10 minute walk, no difference. 11 minute to 20 minute walk, 12% reduction in rates of high blood pressure or hypertension. And over 21 minute walk, a 29% decrease of rates of high blood pressure.
So the authors calculate that with every 10 minute increase in your walk to work, there's a 12% reduction of likelihood of getting high blood pressure.
The second exhibit is looking at stents. This is something we commonly do in medicine.
You can see in the left the artery is blocked. A vascular surgeon is going in, putting in a balloon, and putting in a stent to keep it open. Which makes great sense. So a German researcher named Rainer Hambrecht looked at this with about 100 cardiac patients. He got the group to exercise, and by that I mean 20 minutes a day in an exercise bicycle, and once a week a 60 minute aerobics class, and the other half got the high tech stent and just did their normal activity. And after one year 88% of the exercise group were event free, compared to 70% of the people who got a stent.
So both worked, but I find it sort of incredible that the low tech made a bigger difference.
And you have to remember that the stent just fixes only one part of the heart.
The next way of thinking about it is the reverse. So what I call Sitting Disease.
We know that being sedentary is bad for your health. A researcher called Leonard Veerman wanted to quantify this and he did so down in Australia in a big study they did there. They found compared to persons who watch no TV, those who spent an average of 6 hours a day watching TV can expect to live about 5 years less. I mean that's incredible!
And I think, who watches 6 hours a day of TV? It turns out the average adult in the USA spends about 5 hours a day watching TV, or screens. I find this fascinating that we never think of the TV as something that's bad for our health but clearly it's as powerful as many other risk factors for chronic disease.
So I'm just gonna leave you with two quotes, so one is Jerry Garcia, the lead singer for the 'Grateful Dead'. He said, “Somebody has to do something, its just incredibly pathetic that it has to be us”. And I think that’s true, that in some ways it has to be us.
Hippocrates said “walking is man's best medicine”, so I'm gonna finish by asking you a question, and this may have some personal challenges for you, you know, if you're very busy with work, or kids, or both, or you may be in pain, or have other priorities.
But my question for you is: Can you limit your sitting and sleeping to just 23 & 1/2 hours a day?
So something to think about. Thank you very much.
Hi, I'm doctor Mike Evans and welcome to this visual lecture I'm calling 23 & 1/2 hours.
So I have a big interest in preventive medicine, you know, which can mean a lot of things from cancer screening to eating more fibre, to having a good social network and I mean this in the old sense of the word, weight loss, drinking less, smoking less, controlling your blood pressure, cholesterol and so on and so forth.
All of this things are incredibly important and I wouldn't want you to minimise your efforts in any one category, but I want to know what comes first, what has the biggest impact, what has the biggest return on investment, what makes the biggest difference to your health.
So I did my research and I found an answer to this for me, and it's tricky because all these things are sort of overlapping, but I picked up this intervention because of its breadth and it worked for so many different health problems, and that's what I found so cool about it. Just to walk you through a quick list.
So this intervention in patients with knee arthritis who received one hour of treatment three times a week reduced their rates of pain and disability by 47%. In older patients it reduced progression to dementia and Alzheimer´s by around 50%. For patients in high risk of diabetes when coupled with other lifestyle interventions, it reduced progression to frank diabetes by 58%. Post-menopausal women who had 4 hours a week of the treatment had a 41% reduction on the risk of hip fracture. It reduced anxiety by 48%. In a big meta analysis in patients suffering from depression, 30% were relieved with a low dose and then bumped up to 47% as we increased the dose.
Following over 10,000 Harvard alumni for over 12 years, those who had the intervention had
23% lower risk of death than those who didn't get the treatment.
It's the number one treatment of fatigue, and of course the outcome of choice, my favourite outcome, is quality of life, which is really all of the above, and really about making you life better. And this treatment has been shown again and again to improve quality of life.
So the question is - what's the medicine? And what is 23 & 1/2 hours?
The medicine was exercise.
Mostly walking, so not triathlons, and let me just put it in a different way; I think what I'm asking you to do is if you think about your typical day there's 24 hours. And so you might spend most of your day, you know, this varies, obviously, but, coach surfing, sitting at work, obviously sleeping. And what the evidence I'm about to show you tells me is the best thing you can do for your health is to spend half an hour being active, maybe an hour, and that if you can do that you can realise all the benefits I described in the previous slides.
So let's take a quick walk through some of the literature…
Steven Blair, He´s a professor at the Arnold School of Public Health at the University of South Carolina, and he looked at this in what is called the Aerobic Centre Longitudinal Study, which followed over 50,000 men and women over time and along the left side of this graph is something called attributable fractions, which is kind of a fancy word but it's the estimate of the number of deaths in a population that would have been avoided if that specific risk factor had been erased, for example turning a smoker into a non-smoker, a couch potato into a daily walker and along the bottom are the typical risk factors. You can see that hypertension is incredibly important, and so on and so forth, but the one that kind of implied the most risk was CRF which is Cardio Respiratory Fitness, which is really low fitness.
So low fitness is the strongest predictor of death.
So this is important, because most of the trials we see are funded by Pharma or other companies because they have a drug for high cholesterol or diabetes, but we rarely see fitness thrown into the mix. So it’s nice to see a trial that is not so siloed.
Blair's work is interesting. They also did another trial looking at obesity, and what they found is that obesity and no exercise - that's a very bad combination - and that´s where we saw many of the negative consequences of obesity from a health point of view. But if the obese person was active, even if they didn’t have the weight loss, but were just active and obese that was much, much better, and the exercise ameliorated many of the negative consequences of obesity.
So if exercise is the medicine, what’s the dose?
And when I think of dose, I mean, how long? How often? And how intense?
I´m going to give you a slightly mixed message, but essentially, more activity is better, but I must say that the rate of return seems to decline after 20 to 30 minutes a day. So if you have been active less than 150 minutes a week or more if you´re a kid, an hour a day if you're a kid might fly by, so my personal take on this is that, you know, the literature draws a very broad brush.
And so we see big differences when somebody goes from not doing anything to doing something, and after that the return is more granular. So if we take the nurse´s health study, women who went from 0 activity to just 1 hour a week reduced their heart disease rates by almost half. So you can break it down so its just 10 minutes, 10 minutes, and 10 minutes if you want to do 30 minutes of exercise if you want it broken into 3.
Higher intensity… It looks like higher intensity is equivalent to less time than lower intensity. But I think the clinical pearl is mostly thinking about your style and habits, and your personal cues. So if you’re only going to do it if its pre-booked, with friends, couples who take a half hour walk every morning, or in the evening to organize their life.
A dog is a great walking coach. The data is showing that 67% of dog walkers achieve 158 minutes a week just with the dog walking.
Following of course, your commute, getting off a stop early, taking the stairs, and so on and so forth.
So, thinking about that, I'm just going to walk you through some quick slices of the literature.
And the first one comes from Japan. In the 90's Japan required all employers to conduct health-screens for their employees. And so a large gas company in Japan called Osaka used this to answer a great question. And so people who walked to work, did that reduce their chance of serious health problems? So, in this example: high blood pressure. And what they found is: under 10 minute walk, no difference. 11 minute to 20 minute walk, 12% reduction in rates of high blood pressure or hypertension. And over 21 minute walk, a 29% decrease of rates of high blood pressure.
So the authors calculate that with every 10 minute increase in your walk to work, there's a 12% reduction of likelihood of getting high blood pressure.
The second exhibit is looking at stents. This is something we commonly do in medicine.
You can see in the left the artery is blocked. A vascular surgeon is going in, putting in a balloon, and putting in a stent to keep it open. Which makes great sense. So a German researcher named Rainer Hambrecht looked at this with about 100 cardiac patients. He got the group to exercise, and by that I mean 20 minutes a day in an exercise bicycle, and once a week a 60 minute aerobics class, and the other half got the high tech stent and just did their normal activity. And after one year 88% of the exercise group were event free, compared to 70% of the people who got a stent.
So both worked, but I find it sort of incredible that the low tech made a bigger difference.
And you have to remember that the stent just fixes only one part of the heart.
The next way of thinking about it is the reverse. So what I call Sitting Disease.
We know that being sedentary is bad for your health. A researcher called Leonard Veerman wanted to quantify this and he did so down in Australia in a big study they did there. They found compared to persons who watch no TV, those who spent an average of 6 hours a day watching TV can expect to live about 5 years less. I mean that's incredible!
And I think, who watches 6 hours a day of TV? It turns out the average adult in the USA spends about 5 hours a day watching TV, or screens. I find this fascinating that we never think of the TV as something that's bad for our health but clearly it's as powerful as many other risk factors for chronic disease.
So I'm just gonna leave you with two quotes, so one is Jerry Garcia, the lead singer for the 'Grateful Dead'. He said, “Somebody has to do something, its just incredibly pathetic that it has to be us”. And I think that’s true, that in some ways it has to be us.
Hippocrates said “walking is man's best medicine”, so I'm gonna finish by asking you a question, and this may have some personal challenges for you, you know, if you're very busy with work, or kids, or both, or you may be in pain, or have other priorities.
But my question for you is: Can you limit your sitting and sleeping to just 23 & 1/2 hours a day?
So something to think about. Thank you very much.
