The brachialis is an upper arm muscle that runs from humerus to the ulna . . . the majority of the brachialis is therefore under the biceps. This is significant because intelligent training and the subsequent growth of the brachialis will not only add mass to the arms, but also will actually push the biceps peak higher.
This isn’t to say that just training the brachialis will result in the big guns you’re looking for, as some would have you believe. As usual, the truth is a bit more complex than that.
You see, the brachialis is a relatively small muscle. The biceps is certainly bigger; therefore, in some respects it’s the overall shape and size of the biceps themselves that gives you that awesome front upper arm look that most everyone in the gym is after.
Some of this has to do with intelligent training and not overtraining (which is easy to do with arms), some with genetics—certain bodybuilders are just born with the potential to develop the high peak shape of the biceps that most of us are after.
But if you’re neglecting the brachialis in your training, you’re likely not getting nearly the type of arm development you should be.
I like to do some targeted brachialis training either with or immediately following my direct biceps work. I generally alternate between my three favorite brachialis exercises—standing hammer curls; seated, incline hammer curls; and low-pulley hammer curls with the rope—from one upper arm workout to the next.
As you can probably tell, I’m a big fan of hammer curls—I absolutely love the movement, and when performed properly it can add mass and shape to the upper arms like nothing else. Reverse grip curls also hit the brachialis . . . though I tend to feel the bulk of the stress with reverse grip curls in the forearms and usually save them for my forearm training. [Note: Reverse grip curls can put a lot of stress on your wrists, so I don’t suggest them for anyone who’s had a wrist injury or any significant wrist pain].
Here’s some brief detail on the three hammer curl movements that make up the bulk of my brachialis training:
Standing Dumbbell Hammer Curls
I do these a little differently than most to really maximize the stress on the brachialis. In a standing position, grasp moderate weight dumbbells in each hand. Begin with your arms extended down in front of your body, palms facing in towards your thighs. Perform the movement by alternating arms. Curl your right arm up across your body. Keep your palm facing your body at all times. At the top of the motion your right arm should be directly in front of your left shoulder (for added emphasis, you can supinate your wrist by turning your palm up towards the ceiling in the top position). Now lower your right arm slowly to the starting position and perform the movement with your left arm.
I generally work in the 6-10 rep range for each arm, and I prefer to use moderate weights on this exercise and really do the movement slowly, concentrating on form throughout.
Seated, Incline Hammer Curls
Sit on an incline bench with about a 45° angle with dumbbells in each arm and arms fully extended at the side. Keep your palms facing in towards the bench. Make sure you keep your upper arms as still as possible while you curl the dumbbells straight up. Your wrists should remain locked in position with the palms facing in towards each other. Remember, this is not your standard dumbbell curl where you actually want to supinate the wrists extensively—keep your palms locked in the hammer position here.
This movement can be done by alternating arms—as with standing hammer curls—but with the seated, incline version I prefer to work both arms simultaneously in a nice, steady rhythm.