Repeated collision of your skull, even if it doesn't result in concussion. Linemen are the most prone. https://www.forbes.com/sites/leighsteinberg/2017/07/25/

Repeated collision of your skull, even if it doesn't result in concussion. Linemen are the most prone. https://www.forbes.com/sites/leighsteinberg/2017/07/25/cte-study-sends-shock-waves-through-world-of-football-part-1/#94c4cd54e64d https://www.forbes.com/sites/leighsteinberg/2017/07/25/cte-s...