Star Athletes: Good Genes or Good Training?

Are great athletes born with it? When it comes to professional athletes -- a Michael Jordan or a Serena Williams -- most of us assume they are born with a rare talent. That, yes, they train really hard. But there's something innate that separates them from you and me.

David Epstein set out to find out if that's true scientifically. He's a correspondent for Sports Illustrated and author of the new book,

The Sports Gene: Inside the Science of Extraordinary Athletic Performance

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