There are no effective topicals, at least not proven with weak evidence.
If you are a bodybuilder, and using steroids which contain DHT in them, there is literally nothing that can stop you from balding. minoxidil will give you some regrowth, but it won't last forever.
Even the most powerful oral antiandrogens can't help against these types of steroids. Unfortunately if you are a bodybuilder predisposed to balding you have to choose between being natural or being bald