http://www.nlm.nih.gov/medlineplus/news/fullstory_92440.html
Studies have shown that exercise can help ward off heart disease and cancer, and now new research shows that the reason why may be found within cells themselves.
Endurance athletes had longer telomeres -- DNA at the tips of chromosomes that protect the cell -- in their white blood cells than healthy, nonsmoking adults who did not exercise regularly, German researchers report.
Telomeres can be thought of as the plastic tips on the end of shoelaces, which prevent the lace from fraying, explained Emmanuel Skordalakes, an assistant professor of gene expression and regulation at The Wistar Institute in Philadelphia....
(alternative explanation: people with long telomeres like to exercise)
The cure for a fallacious argument is a better argument, not the suppression of ideas.
-- Carl Sagan