Ever wonder why highly active people seem younger than they are? It may be because their physical activity is making their cells age more slowly.

A study published recently in Preventive Medicine suggests that people who participate in consistently high levels of physical activity have significantly longer telomeres than those who are sedentary, as well as those who are moderately active, according to a media release from Brigham Young University.

Telomeres are the protein endcaps of chromosomes, and they are likened to one’s biological clock and are extremely correlated with age—ie, the older one gets, the shorter his or her telomeres.

Larry Tucker, an exercise scientist at Brigham Young University, suggests in the release that adults with high physical activity levels have telomeres with a biological aging advantage of 9 years over those who are sedentary, and a 7-year advantage compared to those who are moderately active. To be highly active, women had to engage in 30 minutes of jogging per day (40 minutes for men), 5 days a week.

“If you want to see a real difference in slowing your biological aging, it appears that a little exercise won’t cut it,” Tucker says. “You have to work out regularly at high levels.”

To determine his findings, Tucker analyzed data from 5,823 adults who participated in the Centers for Disease Control and Prevention’s National Health and Nutrition Examination Survey. From the index, he also analyzed data from 62 activities participants might have engaged in over a 30-day window, in order to calculate their levels of physical activity.

The shortest telomeres came from sedentary people—they had 140 base pairs of DNA less at the end of their telomeres than those who were highly active. In addition, there was no significant difference in telomere length between those who were sedentary and those who participated in low or moderate physical activity.

Although the exact mechanism for how exercise preserves telomeres is unknown, Tucker notes in the release that it may be tied to inflammation and oxidative stress.

“We know that regular physical activity helps to reduce mortality and prolong life, and now we know part of that advantage may be due to the preservation of telomeres,” Tucker concludes.

[Source(s): Brigham Young University, EurekAlert]