Black belt in Karate.
Frequently has a small role in the films of John McTiernan.
Frequently plays Russian characters (Mind Your Back, Professor (1977), Predator (1987), Red Heat (1988), The Hunt for Red October (1990), Eraser (1996), Best of the Best: Without Warning (1998), Route 666 (2001) and so on).
Gave the 40-pound hammer he wielded in Conan the Barbarian (1982) to the film's director John Milius.
Has been in virtually every Arnold Schwarzenegger movie to date, after arriving in the US in the early 1980s. He has acted in many of the films (including an uncredited performance in Predator (1987) as the Russian General), and has also done many of the stunts and provided training for the actors in most of Schwarzenegger's films.
Has made four movies together with Ralf Moeller (The Viking Sagas (1996), Batman & Robin (1997), The Bad Pack (1997), and Gladiator (2000)). The two are good friends in real life.
Has made four movies together with Jesse Ventura (The Running Man (1987), Predator (1987), Abraxas, Guardian of the Universe (1990), and Batman & Robin (1997)).
Has made six movies with Thomas Rosales Jr. (Raw Deal (1986), The Running Man (1987), Nowhere to Run (1993), Last Action Hero (1993), A Low Down Dirty Shame (1994), and Foolish (1999)).
Has stated that of all the films he has been in, he has only seen Gladiator (2000) and Abraxas, Guardian of the Universe (1990).
Has two children: Michael and Martin, who both have children of their own.
He got into acting by contacting his old bodybuilder friend, Arnold Schwarzenegger.
He is the actor who has appeared in most Arnold Schwarzenegger movies, with a total of 15 and counting (March 2005).
Held the world record in power-lifting (1985 - 242.5 kilo).
His favorite role of his own in an Arnold Schwarzenegger film is 'Nikolai' in Red Heat (1988).
Is a licensed mechanic and during the cold war worked at the DEW Line radar station DYE-3 in Greenland, while it was used by the U.S. Army to look for attacking Soviet planes carrying nuclear bombs.
Is in three films based on the writings of Robert E. Howard - Conan the Barbarian (1982), Conan the Destroyer (1984), and Kull the Conqueror (1997). He also did uncredited stunt work in Red Sonja (1985).
Is in two films based on Tom Clancy's Jack Ryan novels - The Hunt for Red October (1990) and The Sum of All Fears (2002).
Is the founder of various federations, including The Danish Bodybuilding Federation. He also started and co-founded the monthly "Cigar Night at Schatzi on Main" with Arnold Schwarzenegger.
Met his future wife Anniqa Forss in the 1970's when she married his friend, Danish boxing champion Hans Jørgen Jacobsen. She was a Swedish blonde, best known as a snake-charmer and pop singer. They started falling in love in 1980 while returning home from the first Miss Olympia in Pennsylvania, where she was a contestant and he was a judge. They got married in 1982 and moved permanently to the U.S. in April, 1985.
Pursued his award-winning role as Tigris in Gladiator (2000) for over a year, and beat Lou Ferrigno for the part.