7 year old memory: We had an "Oak St Invitational" track meet and "tackle tackle" championship organized by an older boy. I still have a homemade ribbon for winning the javalin (it was a rake handle) I was the last one standing in the tackle tackle game who was not crying. So I guess I won that also.

I have a co-worker whose son is 4. He wants the boy to wrestle.
My advise was to just play with his son and spend time with him.