There has been a steady and resonant drumbeat of news lately, rapping out the profound health benefits of even modest physical activity. I think we can, and should, all pick our preferred drummer, and find a way to march to it.
Among the more noteworthy news items was a Lancet paper some weeks ago indicating that physical inactivity now ranks as one of the top causes of premature death globally. We have long known it made the short list here in the U.S., but a marquee role in worldwide mortality was an eye-opening revelation.
We also had recent research telling us that sitting too much was killing us, and just getting up and off our backsides routinely could serve as an antidote. More specifically, an article in the British Medical Journal indicated that reducing daily time on our tushes to less than three hours could add two years, on average, to our life expectancies.
Now comes the news that just 20 minutes of daily physical activity is enough to be the difference between the onset of diabetes or dodging that bullet in at-risk children.
The study, reported in JAMA, randomly assigned over 200 overweight or obese grade school students to 20 or 40 minutes of supervised aerobic activity five days a week, or to a control group in which habitual activity (or lack thereof) was maintained, for a period of 13 weeks. The primary study outcome was insulin sensitivity, a potent marker of Type 2 diabetes risk; and secondary measures included fitness, and fatness.
Both doses of physical activity significantly improved insulin sensitivity, suggesting diabetes prevention over time. The 40-minute dose exerted a greater effect, but 20 minutes a day was clearly enough to matter.
The higher dose of activity was more effective than the lower at reducing weight and body fat, but both were significantly better than control. And in the case of fitness, measured formally with peak oxygen consumption, both doses were comparably effective, and both much better than control, i.e., doing just about nothing.
So while more exercise is better, some -- and a rather small "sum," at that -- can do a remarkable amount of good. If we know -- and it seems we do -- that fitting 20 minutes of activity in during every school day can be enough to prevent diabetes in a large and growing percentage of our kids, it's hard to believe we would fail to act on that knowledge.
That much more so when we consider that a daily dose of exercise is likely to enhance academic performance, rather than interfere with it. "Sound mind, sound body" should sound familiar, because it's the kind of sensible advice our grandparents gave us. Science now points in the same direction, it just took longer to get there.
Getting to 20 minutes a day is not a big hill to climb. My colleagues and I can provide a boost up with a program called ABC for Fitness, freely available to all courtesy of my nonprofit, Turn the Tide Foundation. Designed for just this purpose -- to give all kids enough daily physical activity to immunize them against serious chronic diseases -- ABC for Fitness reconciles the square peg of physical education to the round hole of the modern schoolday by breaking physical activity up into brief bursts throughout the day, doled out right in the classroom. By teaching during the bursts, teaching time can actually be increased.
We studied the program in over 1,000 children, half receiving ABC for Fitness, the other half a standard curriculum. The daily activity bursts were associated with improved fitness, decreased behavioral problems, preserved academic performance, reduced medication use for asthma, and a 33 percent reduction in overall prescriptions for ADHD. Recess is a far better remedy for the rambunctiousness of young children than Ritalin!
We have reason to think benefits are similar for adults. We know, for instance, from the Diabetes Prevention Program that modest improvements in weight, activity, and diet can prevent diabetes almost two times in three among high-risk adults.
We know as well from the largest available database on sustained weight loss, the National Weight Control Registry, that even modest daily activity appears to be a nearly universal element in successfully maintaining weight over the long term. Doing so, in turn, insulates against all of the major chronic diseases for which obesity is a risk factor, including, but not limited to: heart disease, cancer, stroke, and diabetes.
With that in mind, my colleagues and I have a free program to offer adults, to help fit some or all of those minutes in each day: ABE for Fitness.
I find myself tempted to propose a pledge we all take: the 20 minute pledge. There are 1,440 minutes in every day. Of that total, 20 minutes represents less than 1.4 percent. If a day were a dollar, for a penny and half of it you could pay to keep diabetes away from you, and your children. Not with an absolute guarantee, but with something much closer to it than comes with almost any other investment I can think of.
So the question is this: If a day WERE a dollar, would you be willing to spend a penny and a half of it on drastically reducing your family's risk of ever dealing with diabetes? If yes, you are presumably ready to take the 20 minute pledge. In whatever ways you like best, or work best in your schedule, you pledge to get at least 20 minutes of moderate activity in at least five days a week, and make sure your kids do the same.
I really see only one fundamental problem with all of us owning this simple solution. It's the common problem of preaching to the choir. Those who routinely visit the Healthy Living pages here are probably far less likely than the public at large to need this goad. So if you can, pay it forward.
Better still, we might commit in the might of our multitudes -- as loving parents, grandparents, aunts, and uncles -- to insisting that every school in the country offer every young child the minimal, healthful dose of physical activity. We know how valuable it is, and we know it can be done while promoting rather than hindering academic achievement. And it can be done at no cost. Why should we accept any excuses? If we turned this knowledge into the power of routine action, we would be protecting children from chronic disease, while cultivating a healthy habit to last a lifetime and confer benefit across the lifespan.
All this is a matter of mere minutes a day, minutes that can be the difference between diabetes and staying healthy. That is clearly a difference that matters. We all have the same invitation, even if each of us chooses to march to the beat of a different drummer: to make a small investment of our daily time for a big return in health, for our children and ourselves alike.
For more by David Katz, M.D., click here.
For more on fitness and exercise, click here.