This was a movie definitely made in the 90s.  About a guy that left his little town when he was in high school because he beat up a football player who had hit his kid brother.  He used his karate skills and broke the guys nose.  Years later he comes back to town to find that it has been taken over by a bunch of kungfu masters.  He fights this really fat Asian guy at the end of the movie who is kicking his butt until he starts kicking the guy in his knees.