Steve was natural... his reign was before anabolic agents were introduced into sports. He was very jealous durring Arnold's tenure as Mr. Olympia though... Bodybuilding had a new top contest, not the one that Steve competed in, and bodybuilders looked much more impressive due to steriods. It really made Steve look unimpressive (for those who chose to look to the past of bodybuilding) and he was slightly bitter. He was one of the first bodybuilders to publish his complaints of steroid use in the sport. I believe he got his 'revenge' in his twilight years when it showed that he lived his entire life with an extreemly muscular body and always in good health, when bodybuilders who had reached their fame after him and used steroids were aging terribly, getting sergery after sergery, and dying early.