Here is an interesting article from active.com, Why Too Much Running is Bad for Your Health.
According to the article, the hearts of “chronic runners,” have more coronary plaque build up than sedentary people. Based on a 30 year study 52,000 people, they found that runners have a lower risk of death overall, but that the benefits of running decrease after a certain amount; more is not better. The “sweet spot” seems to be five - 19 miles per week, at six to seven miles per hour, spread over three to four sessions per week.
The article goes on to explain that much of the ill effects of long distance running has to do with the way the body processes free radicals released during strenuous exercise. It seems that the body can naturally deal with a certain amount of oxidative stress, but too much will cause problems. The fact that the problems seen in chronic runners are similar to the problems related to obesity is not surprising since both promote systemic inflammation. The article expands on this a little by suggesting that people don’t run for more than about an hour per session, and suggests performing shorter, higher intensity exercise like sprints.
Of course, if you asked a CrossFitter, we could have told you that short, high intensity exercise is both more healthy for you and provides better results than running for hours at a time. It’s nice to see a similar view coming from outside the CrossFit community, though.
I know we have quite a few distance runners in The Cave. What do you think about this article?