American gymnast Simone Biles is the defending Olympic champion in the individual all-around, and if the high-flying 24-year-old wins in Tokyo she will be the first woman to repeat since Vera Caslavska in 1968. Many consider Biles to be the greatest gymnast of all time. Over the past few years, she has astounded us with never-before-seen moves; there are now four original skills that are named after her. And earlier this year she became the first woman to land the Yurchenko double pike vault in competition.
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