Phenibut isn't for gaining muscle, I don't think. It's a psychotropic drug used in Russia mostly for anxiety and effects some GABA shit in your brain. Apparently they give it to cosmonauts before blastoff. It makes me super focused and feel like Bradley Cooper from that Limitless movie. You just can't use it very often. It also gives me crazy vivid, somewhat lucid dreams. In one recent dream I was sitting on a bench with my friend and a sandwich started talking in his wife's voice and then later we started munching on the sandwich and I was like, "Oh shit! We just ate Sara!!"