Q: What's your secret to building big arms, particularly the brachialis?
A: My blueprint is to use hammer curls to develop thick and bulging brachialis (the knotty muscles on the outside of the arm) and to prod the forearms to swell out at the sides, like Popeye's, as much as they do on the top and bottom.
In the battle to build forearms that attract attention, you're going to need to curl with palms facing in, as if holding a hammer. Here's the repertoire of exercises I suggest for brachialis specialization.
Alternate dumbbell hammer curls Performed either standing or seated, alternate dumbbell hammer curls are the most effective forearm blaster. Barbell curls, indispensable though they are for building the most mass possible in the biceps brachii, do not hit your brachialis as effectively.
A few pointers on form: Stabilize your upper arm against your side to prevent it from swinging. Get a tight grip on the dumbbell, lock your wrist in position, then curl the dumbbell upward through an arc, staying in the same straight-ahead plane. Only your lower arm should move -- the only bending should be at your elbow. At the top, go for a hard squeeze and pause for a peak contraction. Resist as you lower the dumbbell. Keep the pace consistent. Concentrate on perfect technique throughout.
Alternate cable hammer curls Cables can be substituted for dumbbells to maximize brachialis isolation and for consistent range-of-motion resistance. I often mix in cable hammer curls twice in a workout: first as a pre-exhaust movement and later as a working exercise.
Alternate crossover hammer curls Do these standing for a more complete isolation of your brachialis. Follow the hammer-curl alignment -- palms facing in -- and bring the dumbbell or cable up and across your chest toward your opposite shoulder. This technique keeps the weight closer to your body's center of gravity, enabling you to use heavier weights and transfer more effort from the brachii to the brachialis.
Standing cambered-bar curls A cambered bar primarily hits the outer head of your brachii, but it does so with the help of the brachialis -- thereby turning the entire sweep of your upper arm into a craggy rock face of chiseled muscle. Do the bar curls on a preacher bench to place more emphasis on the brachii; stand and curl the bar closer to your body to place the emphasis on the brachialis.
If your brachialis muscles are lagging, prioritize hammer curls in your workout: Pre-exhaust with alternate cable or dumbbell hammers, then start your heavy working sets with either standing cambered-bar curls or standing alternate dumbbell crossover hammer curls. You may even include all of these exercises in your workout without any cost to your biceps brachii development.
Change something in your forearm workout -- exercise selection, rep ranges or the order -- each and every time you train this important bodypart. Keep your wrists locked into position and your elbows close to your body. Squeeze your brachialis and watch them bulge.
Be patient. Be persistent. Utilize the accompanying workouts as a guide. Feel free, of course, to experiment with your own creative variations.