I'm a 3rd dan black belt in taekwondo. I was in the ABC Wide World of Sports Eastern State Karate Championship in Madison Square Garden, New York, 1979. I was just a first dan at that time. I got knocked out in 4th place and the opponent got disqualified. Couldn't continue to fight due to my neck pain. Here's the picture of me during the Brown Belt fight, in early 1979 as well. Yes deaf people can participate in extreme sports!! Update: If you open the picture and look carefully to the right, you will see a guy with white tapes/gloves on, and he wears a light bluish protective face mask. Me? I wear nothing.