Willem "Wim" Ruska was a Dutch judoka and professional wrestler. He is the first athlete to win two gold medals in Judo in one Olympics – in the heavyweight and absolute categories in 1972.

Johannes Cornelius Bluming was a Dutch martial artist, instructor and actor. Known as a pioneer in a variety of martial arts, Bluming held 9th dan in Judo, 10th dan in Kyokushinkai Karate and 10th dan in Hapkido. He was also the coach of two-time Olympic champion Willem Ruska.