Started to learn judo at age 13 from his stepfather Dan Oka. Earned a black belt in Karate under trainer Oshima and is a 9th degree black belt in Judo. He won five consecutive national championships from 1965 to 1970 and ranked 5th in the world in 1965 and 1967.He is a two-time Black Belt Hall of Fame member. Nishioka is a Class A rated national coach and a Class A rated International Judo Federation referee.
