I am not a marathon runner but was shocked all the same when I read this article in Discovery News. We can probably expect to see considerable research (and a lot of heated debate) focused on validating these findings.

http://news.discovery.com/human/health/how-you-can-be-fit-but-not-healthy-140328.htm#mkcpgn=emnws1

Well of course you can exercise every day and if you don't eat right you will have a heart issue. There are many physically fit people that end up having strokes, heart attacks and other diseases because they think because they exercise they are doing themselves justice when they eat crappy.

Certainly is a reminder that running marathons does not negate the need to eat healthy as well isn't it? What I found surprising is the theory that long distance running may result in arterial damage - "...one theory is that the extra twisting and pumping motions induced by repetitive exertion might put too much wear and tear on the arteries, leading to a type of scarring called fibrosis." Or the other theory mentioned in the article - "It's also possible that over-exercised hearts suffer from chronic stress and the need to constantly repair damage induced by excessive free-radical production."

Even more surprising - "One long-term study of 54,000 Americans, published last year, found the lowest rates of death among people who ran 5 to 20 miles a week. People who ran more than 25 to 30 weekly miles, on the other hand, lived no longer than people who were inactive."

Too much of a good thing?

The heart is a muscle. You can underwork it or overwork it like any other muscle in your body.