May 28, 2010 -- Short bursts of vigorous exercise -- the kind that makes you really break a sweat and increases your heart rate -- may help buffer the devastating effects that stress can have on cellular aging, a new study finds.
Brief bouts of vigorous physical activity reduced one of the key signs of cellular aging: telomere shortening. Telomeres are tiny strips of genetic material that look like tails on the ends of our chromosomes. Telomere shortening is a known indicator of aging in cells. The study appears in the May 26 online issue of PLoS ONE.
In the study, 63 healthy older women were divided into an inactive group and an active group, based on their exercise levels over a three-day period. Many of the women were highly stressed caregivers for spouses or parents with dementia. The women in the inactive group who reported high stress levels had shorter telomeres; the active women in the high-stress group did not have shorter telomeres.
Put another way: the women who engaged in brief vigorous physical activity -- at least 40 minutes over the three-day study period -- and were stressed had longer telomeres than their inactive, stressed-out counterparts. The authors conclude that 13 minutes or more of vigorous exercise daily appears to be the critical amount correlated with longer telomeres.
“Physical activity is so good for you and stress is bad for you, but the new study shows the stress-buffering effects of physical activity in those who are chronically stressed,” says study author Eli Puterman, PhD, a health psychologist at the University of California at San Francisco.
“People know stress is bad for the heart and makes you look tired and haggard and makes us more vulnerable to infections,” Puterman says. “And there is so much accumulating evidence that links stress to health, so to show that there is something we can do when we are stressed that can delay or buffer the impact is exciting.”
As far as a stress-busting exercise prescription goes, Puterman says that the CDC recommendation of 75 minutes of vigorous activity or 150 minutes of moderate activity, plus weight-bearing exercise every week for adults, will suffice.
“That is a great prescription in my mind,” he says.