Live Long and Perspire: Exercise may slow aging at chromosomal level

The long-observed association between exercise and a slightly longer life span may have its origins in DNA maintenance, a new study finds. Researchers report that the ends of chromosomes hold up better in active people than in sedentary individuals, possibly extending cell life and contributing to overall survival.

Those ends, called telomeres, consist of repeating DNA segments that guard the ends of chromosomes much as plastic tips preserve shoelaces.