I took octopamine for a while when I was bodybuilding. It didn't seem to make much of a difference first, but I started with a low dose (200mg) and increased it over time to almost 1000mg. It might be too much for some people, but it worked well for me.
As the dose went up, I started seeing more and more difference with my body. I know it was the octopamine because I didn't take any other supplements or change my training/diet in any way in that time frame. It helped me get rid of my excess fat and build up more muscle. My body was the leanest it has ever been. I stopped taking it because it was getting way too expensive.