Speaking as a 17 year old who is interested in sports and have parents who DIDN'T push, maybe you should just let him go through stages. Then, eventually I believe, he will come to like sports. When he becomes interested in one, push him to be the best. DON'T OBSESS it, but encourage practice time, and give rewards for practicing and such. I BELIEVE that most kids DON'T become interested in sports because their parents tried, it's part of their personality. If he doesn't like sports, try to find a sport that fits his personality. He'll EVENTUALLY come around