Can Over exercising be detrimental

 Of course too much of just about anything can be detrimental, but the threshold for exercise on heart disease seems to be very high. A recently published 5 year study on 90,000 healthy individuals that used accelerometers to measure physical activity found that there was no maximal amount of exercise that increased risk for heart attack or heart disease.

Can You Exercise Too Much?

New research shows marathoners have less arthritis than non-runners

Many people have heard that higher mileage running is bad for the knees and increases the chance of arthritis. There has never been any good evidenceto support that contention. A new study from the Journal of Bone and Joint Surgery showed that long term marathoners had half the incidence of knee and hip osteoarthritis as matched controls of non runners.
Does this surprise anyone?
New research shows marathoners have less arthritis than non-runners

Going from the 38 year old winner of the Boston Marathon to the 91 year old woman who just set an over 90 year old age group female marathon record.

hoo.com/blogs/abc-blogs/91-old-marathoner-smokes-competition-153723959--abc-news-health.html