Mark Allen (born January 12, 1958 in Glendale, California) is the second six-time Ironman Triathlon World Champion. He graduated from UC San Diego, where he was an All-American swimmer, with a degree in biology.
After competing and losing in the Ironman Triathlon Championships six times (often to Dave Scott), Allen emerged victorious in 1989, winning one of the most difficult one-day sporting events in the world.
It would be the first of six Ironman victories for Allen, the last coming in 1995 at age 37. He has also excelled at the Olympic distance, winning the sport's inaugural World Championships in 1989 in Avignon, France, by more than a minute. He was undefeated in 10 trips to the Nice International Championships, and from 1988-1990 he put together a winning streak of 20 races.
Over the course of his racing career, which ended in 1996, he maintained a 90% average in top-three finishes. He was named Triathlete of the Year six times by Triathlete magazine, and in 1997 Outside magazine tabbed him The World's Fittest Man. Allen was inducted into the Ironman Triathlon Hall of Fame in 1997.
Allen married fellow triathlete Julie Moss in 1989. They divorced in 2002.