When The Mag started kicking around ideas for the Body Issue, we all took it for granted that pro athletes’ bodies had changed for the bigger over the years. But Insider wanted to know exactly­ how the average jock was different now from when their sport went pro. So we looked at mounds of raw data (courtesy of Gary Gillette and Pete Palmer, editors of the ESPN Baseball Encyclopedia and ESPN Pro Football Encyclopedia) for the NFL, NBA, NHL and MLB - thousands of players from all-stars to one-and-dones. What’d we find?

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