Background
Sekine was born in Ōarai, Ibaraki, and entered the Tokyo Metropolitan Police Department after graduating from Chuo University.
関根 忍
Sekine was born in Ōarai, Ibaraki, and entered the Tokyo Metropolitan Police Department after graduating from Chuo University.
Chuo University; Osaka University.
However, judo was not included in the program for the 1968 Summer Olympics, and Sekine entered the Olympics for the first time in 1972 as a 28-year-old veteran after winning the All-Japan Judo Championships that year. Oh had been leading in points for most of the match. Sekine retired shortly after winning the Olympic gold medal, and served as a coach and advisor for the All Japan Judo Federation, and as a referee during the 1996 Summer Olympics.
He has also worked as an instructor for the Tokyo Police Department, and Heisei International University.