The concept of using weights to increase strength for athletics was considered nearly cheating during the 1930s. There was a belief among athletes that using weights would make athletes muscle-bound and reduce your flexibility. However that false idea changed somewhat by the 1950s. Steve Reeves, Clarence Ross, and Reg Park being the influential ones rose in the field of muscle. However as time passed everyone recognized the fact that Reg Park was far above all other bodybuilders. He dominated the field for the next 20 years!.
During the 60s the aura of bodybuilding continued. Arnold Schwarzenegger the king of bodybuilding arose. In addition, his some of his competitors were Frank Zane & Franco Columbu (A very good friend of Arnold). However, the biggest threat and challenge to Arnold was the great Sergio Oliva. Arnold had once said "Sergio's shirt would come off, he would then look you in the eye, then the mirror, exhale with an animal grunt, suddenly his lats would flare, just when you thought that this guys is huge, BOOM!, he would become even more bigger, more and more, until you began to doubt that it was a human being you were looking at." As the 60s ended six dominant names emerged, Dave Draper, Sergio Oliva, Bill Pearl, Franco Columbu, Frank Zane, and the legendary Arnold Schwarzenegger.
IFBB was formed during the 1970s. International Federation of Bodybuilding was the dominant bodybuilding organization, under the guidance of its founders the Weider brothers, Ben and Joe Weider. The IFBB consisted of over 100 countries as members, and was one of the largest sports federations in the world! Its top title, Mr. Olympia was the recognition of the biggest most muscular man in the world. The title is comparable to winning Formula 1, like Michael Schumacher.
Bodybuilding changed a lot in the 80s and 90s in terms of size vs. symmetry. Lee Haney broke Arnold's record of seven Olympias by winning eight.