I dont know about that one, I broke my ankle, chalor bone, and compressed my spine playing football. Plus cauliflower ear can be drained. I bet more children are hurt per capa in football with major injuries. Not say it's not dangerous, or your kids wont get hurt. Kids play and get hurt. I might have a different outlook if I had kids. I want and plan on having them and as of right not if they wanted to train in MMA i would let them.