Back to her roots: How Katie Ledecky became so dominant in the pool

“She’s a mystery,” says Dave Marsh, coach of the U.S. Olympic women’s team. “I’ve experienced the passion and depth with which Katie trains and races. I’ve gone back and tried to figure out what causes it, because she doesn’t fit the model. She has a wonderful family, has everything, really, that she wants; she’s a beautiful person with seemingly no dark sides. But she has this energy stirring in her, not just at meets but at practice.

“What is she pursuing? Her personal best, but she’s doing it with fury. Where’s the fury coming from? We don’t know, but the stove is running hot.”

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