He won six medals at the World Championships in 1966, including three gold medals in the team all-around, the floor exercise and the horizontal bar. Two years later, with four gold, one silver and one bronze medals he became the most successful male athlete at the 1968 Summer Olympics. In 1970, he won another four world titles: in team competition, on rings, floor and parallel bars. He won four more medals at the 1972 Summer Olympics.
After retirement he was the vice-president of the Japanese Gymnastics Federation. He also served as a gymnastics coach at his alma mater, Chukyo University. In 2005, he was inducted into the International Gymnastics Hall of Fame.