A study of 396 ultramarathoners found that while many suffer injuries throughout the course of their race, the vast majority of them are minor. Researchers looked at medical data on runners who competed in Racing the Planet 4 Deserts series, a four-part ultra-race that takes place over seven days in rough terrain on four continents. Runners travel 150 miles per race.

What group of people is this study excluding?  Right, all the people who got injured training, and all the people who have quit running.  To really make the point, it also does not include people who possibly died from running.  This is a blatantly flawed study.

Ultramarathoners suffer injuries but most may be minor, a study finds