My gym used to be able to get something called EPH which was a ephedrin, caffine and asprin tablet. 2 of these and you get a major buzz!

I've used a course of them taking them in the morning and before training. It really did help shed the fat, but you can feel your blood pressure raise, and I walked around like I was constantly pumped up.

One guy took them at 8pm and wondered why he couldn't sleep. I wouldn't recommend taking them past 5pm.