The only concept of morality that has any basis in reality is the non-aggression principle. All other concepts of morality do not exist and are, in fact, a violation of the non-aggression principle because they do not respect self-ownership and individual autonomy. On the basis, bodybuilding can be evaluated only on its functional impact upon those that do it. That is, does in improve health and longevity? Or does it reduce such. All getbiggers are well aware of the adverse effects of PEC's and the many early deaths that have resulted from such. But is this also true for natural "bodybuilding"? Someone can correct me if I am wrong. But I am not aware of any objective evidence that natural bodybuilding is detrimental to long term health and vitality. Indeed, there is considerable evidence that natural resistive weight training improves long term health and vitality and can help prevent sarcopenia as well as osteoporosis, which are the two leading causes of disability in older people. It is irrational to evaluate bodybuilding, or any other self-modification technique on any other basis.
Your mission, if you accept it, is to make it to LEV (longevity escape velocity). If you accept this mission, all world-views that imped your efforts to accomplish such become totally null and void. Call it a transhumanist wager.