Can exercise keep you young?

Source: The New York Times, Well Blog; The Proceedings of the National Academy of Sciences

A study has found that exercise reduced or eliminated the effects of aging in mice genetically programmed to age more quickly (their mitochondria repair mechanism was compromised). While half of the mice remained sedentary for a year, the other half were allowed to briskly run on a wheel for 45 minutes, three times per week for five months.The exercise is equivalent to a person running 6.2 miles in 50-55 minutes.

While the sedentary mice were bald, weak, and dying at 8 months, the active mice remained energetic and had dark fur, full muscle mass and brain volume. At one year, all of the sedentary mice had died while all the active mice were still alive and had overall more healthy mitochondria than the sedentary ones.

While it remains a mystery exactly how exercise alters the aging process, this study shows that exercise can affect mitochondria function, and thus the course of aging.