Gloria Estefan had a point when she belted out, "Get on your feet. Get up and make it happen. Get on your feet. Stand up and take some action."
Turns out that sitting too much is not only linked to a number of ailments, including obesity and diabetes, but a new study shows being a couch potato also ages your cells faster. The study, which focused on women, found that those who didn’t meet the recommended 30 minutes of moderate-to-vigorous physical activity daily and spent more time sedentary (about 10 hours or more sitting around) were aging at a quicker rate than those who, well, got on their feet and made something happen.
Inactive women who spent more time sitting were, on average, about eight years older in biological terms than those who were inactive but spent less time sedentary. The aging-quicker group had shorter telomeres than those who spent less time sitting every day. Telomeres, those shoelace-like tips of tightly packed DNA found in every cell, shorten as we age but the pace this happens can vary greatly.
The scientists led by Aladdin Shadyab, of the University of California San Diego, tracked how sitting affected the women’s chromosomes by taking samples from almost 1,500 older women enrolled in the Women’s Health Initiative, a long-term study of chronic diseases in post-menopausal women. They concentrated on telomeres because previous studies have found that since telomeres shorten as our cells divide and age, their length can indicate how old a cell is, and how old we are on a biological level, not just chronologically.
For the study, published in the American Journal of Epidemiology, Shadyab and his team compared telomere length to how much the women exercised. To record the amount and duration of physical activity, they had the women wear accelerometers for one week.
For those who got the recommended dose of daily exercise, sitting did not affect their telomere length. But if the women didn’t exercise daily and spent more than 10 hours a day as couch potatoes, their telomeres were shorter and the biological age of their cells older.
"Women who did not meet the physical activity guideline and were sedentary for at least 10 hours a day were biologically older; their cells are aging faster than those of women who were less sedentary," Shadyab told Time.
How much physical activity is actually needed to offset all that sitting around isn’t clear yet, but in the meantime, follow Estefan’s lead: Get on your feet. Get up and make it happen.