Most non-traumatic fatalities among high school and college football athletes do not occur while playing the game of football, but rather during conditioning sessions which are often associated with overexertion or punishment drills required by coaches and team staff, according to research presented today at the American Orthopedic Society for Sports Medicine Annual Meeting. The research was presented by Dr. Barry P. Boden of The Orthopaedic Center, Rockville, Md.
source https://www.lifetechnology.com/blogs/life-technology-news-blog/over-conditioning-kills-non-traumatic-fatalities-in-football-is-preventable