Four-time K-1 World Grand Prix champion. He won the 1997, 1999, 2000, and 2002 WGP's. In 2002, he was able to win despite losing to Bob Sapp twice. In the first round he lost to Bob Sapp, but when Sapp's second-round opponent Semmy Schilt was forced to withdraw due to injury, he replaced him. Sapp beat him again but injured his hand, enabling Hoost to then replace Sapp and go on to defeat Ray Sefo and then Jerome LeBanner to win the GP.