Injured Shot Putter Assumed The Risks

Should a high school shot-putter that was injured by a shot thrown by his opponent be compensated because of his injury?  According to Injured Shot Putter Chances In Court Are Shot, the plaintiff had participated in numerous track meets and had thrown the same shot hundreds of times.  I fully agree with the courts in this case.  The participant assumed the risk by participating in the event and had experience and knowledge of the game to know he could get injured. There is no difference in this incident and that of a football player running off of the sidelines and hitting the players or cheerleaders on the side. The sideliners know that if they are standing there, someone may hit them.