Primobolan steroid/Methenolone acetate bodybuilding Primobolan steroid, chemical name Methenolone, is by far the most popular injectable anabolic androgenic steroid (AAS) for cutting cycles. The only steroid that’s more popular in cutting cycles is trenbolone. You’re probably wondering the reason it’s so popular, right? Ironically, primo is popular for one big reason: Arnold Schwarzenegger. I’m not sure where the rumor came …