Originally Posted by
matheje
I did bis yesterday, and did db preacher curls. I didn't do exactly as you suggested, but I did have the seat fairly high and, doing on arm at a time, I concentrated as hard as I could on not using anything but the bicep...and the left arm was clearly stronger than the right, which I did not think was the case...this tells me all along I've been using other muscles on my right side to get the same reps I do on my left with just the left bicep.
So going forward I'm going to be super strict on bi's (and everything else) and do primarily or maybe solely, dumbells. My right tricep is also smaller than the left, so I'll apply this same principle to tri's and see how things go.