clen, on paper and in studies, seems to be a great cutting drug. I dont have any personal use for it so cant really speak on first hand experience. But its a B2 agonist, so when you work out your HR will go up more than normal due to compensatory mechanisms and if you take enough of it, it will hit the B1 receptors also.

Sounds like you are taking enough, due to the shakes, so how about everything else that would go into cutting? diet and cardio?