My arm isn't huge. It's a little toned, mostly in the forearm but very little in the biceps. So what I am wondering is if I should work out my biceps. I've always thought that getting more speed off your arm was more important than power. And I have read that the power and speed to hit a ball is going to come from the waist, rotatory cuff, and forearm, and not much about the bicep. But then you can look at Nadal and.. well that kind of speaks for itself. So biceps, how important can they be tennis wise? Should I even bother working them out?