When I play sports I always hurt people.
I don't think you're supposed to do that unless you have a good reason for hurting people.
Id rather people not be too aggressive towards me.
Participating in sports is a good idea however you should not be going out of your way to intentionally hurt others. Might be a good idea to examine why you feel the need to try and hurt other people in this way.
It's my way of protecting myself. If people see me hurting others they will leave me alone.
You might be playing the wrong type of sport if you feel the need to do this. Try finding a sport that's more in tune with your comfort level. Then you'll have a better time, and people won't get hurt.