-- you can read the excerpts below or the entire 6 page article--
Basically the research shows that running marathons does not increase the chance of dying. In fact excercise, no surprise, is good for you (lower weight, better blood pressure, etc.) but of course there is the matter of degree. Running a marathon includes 4 months of training (I have started 4 and finished 3) and is more extreme than say regular excercise. Deaths during marathons get headlines but there is nothing to show that it is the cause of the death....other than enlarged hearts in marathoners and ultra runners (100 miles or so) and triathletes.
I am not defending it
because I am a runner - I am defending it because all the evidence says otherwise. I completely understand that what I am posting comes from a marathoner and from a running magazine-granted.
When I first read this story yesterday the first thing I thought was "enlarged heart" but now I read about the heat. Heat, not the excercise, is probably what did him in...other than existing conditioners internally that he didn't know about.
For what it worth. Gotta go- it is only on weekends that I get to run in the light of day. 5 miles today I think. Wish me luck!
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To find out, I visited the world's leading heart and exercise experts, reviewed stacks of medical research about exercise and death risks, and consulted with the statisticians who work in this field. I learned the reassuring truth that running and other vigorous exercise does dramatically lower mortality risks. But I also learned that there are surprising paradoxes, and no guarantees. Every workout is a bit of a crapshoot. Fortunately, if you run smart and fully informed, you should be able to keep going for a long, long time.
Since the mid-1970s, three independent groups have collected data on heart-attack deaths during marathons. When the results are pooled together, we're looking at more than 4.5 million marathoners over the last 30 years. Of these, 41 runners died of heart attacks, a rate of one in every 110,476 marathoners. However, the two best of the three marathon studies have produced death rates somewhat higher than this average.
In London, cardiologist Daniel Tunstall Pedoe served as London Marathon medical director from the inaugural 1981 marathon, which he ran in 3:19, through the 2007 event. Pedoe has studied marathoner deaths during all 27 London Marathons. Almost 712,000 runners have completed the race, with eight dying from heart attacks, a rate of one in every 89,000. The eight London deaths included five attributed to artery disease (cholesterol deposits) and three to structural heart abnormalities such as those that killed Ryan Shay and Chad Schieber. The deaths have occurred all along the course-at miles six, 10, 11, 12, 18, 19, 24, and in the finish chute. "Marathon running has a comparatively low, but not negligible, risk, and it's not surprising that people are frightened when they hear about a marathon death," says Pedoe. "That's why we have to keep educating everyone about the lifetime benefits of exercise."
http://www.runnersworld.com/article/0,7120,s6-238-244--12968-1-1X2X3X4X5-6,00.html