Tutorial: Alternating Dumbbell Curls
This is a great exercise to help build up those PEAKS on your biceps!
The key is full range of motion - notice at the top of the rep I'm rotating my palm and bringing my pinky to my shoulder, twisting the wrist and getting that extra SQUEEZE at the top.
Notice the veins in my arms and how after every rep they look a little bit thicker? That's blood being pushed into the muscle. This exercise is just like the little squeeze ball while you give blood. You're forcing blood into the muscle, causing the fibers to break down and adapt.