If you're looking for another reason to exercise regularly, please think of your telomeres. A new study finds that adults who are highly physically active—meaning for women 30 minutes of jogging a day (40 minutes for men), five days a week—had telomeres with a biological aging advantage of nine years over their sedentary counterparts. And, you might be chastened to know, the highly-active adults even had a seven-year advantage over those who only moderately exercise. If you want that telomere edge, you're going to have to work for it.
Well, okay, but what are telomeres, and why do they matter? We're talking about aging at the cellular level: Telomeres are found at the end of human chromosomes; they're made of protein, and every time a cell replicates, the telomeres get a little shorter. So as we age, the cells in our body replicate, and the telomeres get shorter. Scientists are investigating what effects this can have; so far, they've connected it to an increased cancer risk, among other things. The current study, conducted by Larry Tucker, an exercise science professor at Brigham Young University, used the CDC's National Health and Nutrition Examination Survey, focusing on data from 5,823 adults. Based on their physical activity over a 30-day period, they were filtered into groups and had their telomere lengths compared. He found that sedentary people had the shortest telomeres. (To get technical, they had 140 fewer base pairs of DNA compared to the frequent exercisers.) And there wasn't much difference between them and the low or moderate group—only the most physically active people showed a marked advantage. Why that's so isn't yet clear. Tucker, though, suggests it may relate to inflammation and oxidative stress, two factors that can be suppressed through exercise. The benefits of exercise in reducing mortality and prolonging life may come from its effect on telomeres. That doesn't mean you can start bragging about how your lengthy telomeres are going to add another nine years to your life. But it's extra evidence for a much more prosaic takeaway: Regular exercise, with all due apologies to Donald Trump, is actually good for your body.
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