Back in 2012, Katie Ledecky was a 15-year old high schooler, the baby of the US Olympic swim team, and an athlete full of untried potential. Upsetting the field in the 800-meter freestyle and obliterating a world record ensured that none of her opponents would underestimate her again. Since that breakout performance, Katie has gone on to win six Olympic medals (so far) and 15 world titles, the undeniable, practically-unbeatable superstar of swimming.
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