It depends on (a) genetics, and (b) hormone supplements. Natural body building is therefore more dependent on genetic variation and slower. There was a recent

It depends on (a) genetics, and (b) hormone supplements. Natural body building is therefore more dependent on genetic variation and slower. There was a recent 'study' (most research in this area is pretty bad, small sample sizes, low powered studies) that showed muscle/size improvements: hormones + exercise > hormones > exercise > neither.