The Oldest Professional Athlete Was 104.

John Whittemore was a track athlete for a very long time. He finally made it into the record books at the age of 104, by officially becoming the world's oldest athlete. His last competition in 2004 was just before his 105th birthday and less than a year before he died in 2005. He threw the javelin and the discus for the event. According to Whittemore "if I don't drop it on my foot, I set a world record".
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