Running 26.2 miles may make you sweaty and sore, but it won’t give you a heart attack, found a new study. The finding offers a comforting counterpoint to the media frenzy that often follows when someone drops to the ground with cardiac arrest during a marathon. In the majority of cases, the new study found, athletes had a preexisting heart condition that would've likely become a problem even if victims had never signed up for a long-distance event…But hypertrophic cardiomyopathy also showed up in runners over age 40, and that is a new and interesting finding, said Michael Joyner, an exercise researcher at the Mayo Clinic in Rochester, Minn. It means that congenital heart problems might not surface until much later than researchers previously thought.
Discovery News, by Emily Sohn, 1/11/2012