Dean Rutz/The Active Times

Age: 25
Decathletes are jacks of all trades, well-rounded athletes who master 10 track and field disciplines—100 meters, pole vault, shot put, long jump, 400 meters, javelin, high jump, discus, 110-meter hurdles and 1500 meters. It's such a difficult, grueling competition that the Olympic gold medalist is named the “World’s Greatest Athlete,” a tradition started by no-nonsense King Gustav V of Sweden at the Stockholm Olympics in 1912. Ashton Eaton, the 2012 Olympic champion, has not only proved himself to be the best, but also shattered a decade-old world record, prompting many to recognize that, this time, the title may be more than a traditional honorarium.
—Peter Koch
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