Nov 30, 2012 12:34 AM GMT
A fast-emerging body of scientific evidence points to a conclusion that's unsettling, to say the least, for a lot of older athletes: Running can take a toll on the heart that essentially eliminates the benefits of exercise.
"Running too fast, too far and for too many years may speed one's progress toward the finish line of life," concludes an editorial to be published next month in the British journal Heart.
Until recently, the cardiac risk of exercise was measured almost exclusively by the incidence of deaths during races. For marathoners, that rate was one in 100,000—a number that didn't exactly strike fear. Moreover, data showed that runners generally enjoyed enormous longevity benefits over nonrunners.
What the new research suggests is that the benefits of running may come to a hard stop later in life. In a study involving 52,600 people followed for three decades, the runners in the group had a 19% lower death rate than nonrunners, according to the Heart editorial. But among the running cohort, those who ran a lot—more than 20 to 25 miles a week—lost that mortality advantage.