From the first game of the National League of Professional Baseball Clubs on April 22, 1876, tens of thousands of men have played professional sports in the Big Four--baseball, basketball, football, and hockey--major professional sports leagues in the United States. Until April 29, 2013, however, when National Basketball Association center Jason Collins came out publicly as gay, not one of those tens of thousands of men had ever come out to the public as gay while an active player on a major league roster. Is it because gay men can't jump (or throw, or catch, or skate)? Or is it more...