Paul Solotaroff traces it:
[I]f you were born anytime after the release of Conan the Barbarian in 1982, it may shock you to learn that as late as the 1970s, Americans were repelled by the sight of brawn.
"I’d go to the beach, and they’d give me the wolf whistle, guys on a blanket wanting to fight," says Eddie Giuliani, the 1974 Mr. America (short division) and one of the early legends at Gold’s. "Nobody liked guys with the lumps back then. They thought we were all morons and fairies." George Butler, codirector of Pumping Iron — the landmark documentary that made a rock star of Schwarzenegger and almost single-handedly changed America’s view of well-built men — says, "I always liked to walk behind Arnold in the street so I could check out people’s reactions as we passed. They’d point at him and sneer: 'God, look at that fucking freak. What a clown.'"
The Dish 