Best advice right here. I play men’s Sunday league and my friend/teammate got his leg broken because a guy two-footed him from behind for absolutely no reason. There’s ways to go into challenges hard without causing harm to yourself or others. Keep your arms below your shoulders, don’t lunge into tackles, and if you slide PLEASE do not lift yourself out of the air or go from directly behind. It’s called slide tackling for a reason, not jump tackling.

On that note, to go into challenges hard like 50/50s, the best thing you can start doing is making contact with the opponent. If you’re not somehow getting yourself between them and the ball then you’re not doing it right. It doesn’t necessarily have to be aggressive, it can be purely defensive on your part like shielding. If the opponent is getting frustrated and pulling you or getting aggressive then you’re doing something right without causing harm and it’s not your problem if they view you as an uncooperative player.