Career
He started mastering in Judo, learning under Jon Bluming, in 1960 and traveled to Japan for further training. His success at the 1972 Summer Olympics was overshadowed by the Munich massacre that took place days before. He retired after the 1972 Olympics and later took part in professional wrestling, competing between 1976 and 1980 for the New Japan Pro Wrestling and World Wrestling Federation promotions.
In August 1976, Ruska defeated Ivan Gomes in a vale tudo bout in Brazil.
Details about the fight are sparse, but it is known that Gomes threw illegal strikes and that the event result was controversial. At the end of the match, Gomes took Ruska"s back and tried a rear naked choke, but they became tangled on the ring ropes.
They had a falling out after Dolman joined Akira Maeda"s Fighting Network Rings while Ruska was part of Antonio Inoki"s New Japan Pro Wrestling, but they mended it in September 1997, when Inoki visited Holland along with Naoya Ogawa. They stayed in contact until Ruska"s death in 2015.
In 2001 Ruska suffered a major stroke which left him physically disabled.
In 2013 he was inducted in the Hall of Fame of the International Judo Federation. Ruska was admitted to a nursing home in 2014.