The fabled "fountain of youth" may lie in physical exercise--literally.

Ever wanted to run from old age? New research in both mice and men demonstrates literally running regularly helps prevent cells from getting older! German investigators have found that regular physical activity helps you maintain longer telomeres--DNA sequences at the end of chromosomes that typically get shorter with age. These longer telomeres prolong the life of cells in blood vessel walls and white blood cells that circulate in the blood. Both middle-age runners and younger track-and-field athletes had longer telomeres than older sedentary controls.

PositiveTip: Regular physical activity has exciting anti-aging potential. It is unfortunate we don't do more!