Dumbbell concentration curls is an excellent isolation exercise that mainly targets the biceps and brachialis. This movement is very effective for developing the “peak” of the biceps muscle. In addition, you can use this exercise for fixing symmetry issues (such as having one arm bigger than the other).
The concentration curl is an great exercise for isolating and for stimulating the muscle fibers on the peak of the biceps. Which is extremely beneficial for both aesthetics and when competing in bodybuilding contests.