Holds the record for most Iron Man World Championship victories ever (along with his rival Mark Allen, who managed to rack up an equal number of wins). The Iron Man competition, which consists of a 2.4 mile swim, a 112 mile bike ride and a 26 mile marathon run, is one of the most strenuous physical feats in the world. And Scott won six of them, all while vegetarian. He even came out of retirement at 40 to compete again, and took second place. Today, at age 55, he still participates. In other words, this is one gnarly vegetarian dude.

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Robert Parish

One of the greatest NBA basketball players in history, vegetarian Robert Parish played center for the Boston Celtics alongside Larry Bird. He was inducted into the Basketball Hall of Fame in 2003. Measuring over 7 feet tall, he was an imposing force on the court, yet was renowned for his versatility as well--and his high release jump shot was legendary.

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Billie Jean King

Billie Jean King, a longtime vegetarian, has also been an inspiring force against sexism. Along with wining 12 Grand Slam titles and 16 Doubles titles , she's famous for her Battle of the Sexes match, in which she defeated former men's Wimbledon champion Bobby Riggs.