As recently reported in The New York Time, a recent study at Johns Hopkins University explored this question. They found that even as marathon participation almost doubled during the past decade, to more than 473,000 finishers in 2009 from about 299,000 in 2000, the death rate was low and remained unchanged. 28 people died during or in the 24 hours immediately after a marathon, most of them men, and mostly from heart problems. That comes out to less than one death per 100,000 runners.
“Our data shows, quite strongly, that marathon running is safe for the vast majority of runners,” concluded one researcher. For many of the runners, marathoning likely saved them from suffering a heart attack that might otherwise have been brought on by a sedentary, unhealthy lifestyle.
So keep running and racing!