[1] Okano entered the 1964 Summer Olympics while studying at Chuo University's law school, and won the gold medal in the middleweight division.

He won another gold medal at the World Judo Championships in 1965, becoming the champion of his division at only 21 years of age.

[1] Okano suddenly retired from competitive judo at only 25 years of age, and founded the Sekijuku (currently the Ryutsu Keizai University's judo team) in 1970, where he instructed future Olympic gold medalist Kazuhiro Ninomiya.

[3] Also known as a master in the field of newaza, Okano is considered by some an important contributor to the late art of Brazilian jiu-jitsu.

[4][5] He was a teacher to Brazilian jiu-jitsu black belts like Joe Moreira, Fredson Paixao, Edson Carvalho and Oswaldo Alves, with the last citing their training with Okano as instrumental for the development of sweeps, side control and guard work in modern jiu-jitsu.