How to Build Arm Muscle (4 steps)

Building arm muscles takes regular, high-volume, weight-training workouts that target the biceps, triceps and forearms. High-volume weight-training workouts feature a high number of exercises, sets and reps. Even though your focus here is the muscles in your arms, your workouts should contain compound, multi-joint exercises that work other muscle groups in addition to isolation exercises that specifically target the arm muscles.

Scheduling Your Arm Workouts
In a muscle-building weight-training program, allowing your muscles enough rest is as important as the workouts themselves. Therefore, to give your arm muscles adequate time to fully heal between workouts, schedule just two arm-focused workouts into your training regimen every week. Spread out your workouts throughout the week so that there are two to three days off in between, such as a Monday and Thursday routine.

Starting With Compound Lifts
Compound lifts require movement at multiple joints and therefore work numerous muscle groups. For example, chinups require your shoulders and arms to move and therefore build strength and size in your latissumus dorsi, which handle movement at your shoulder joints, and your biceps brachii, which control movement at your elbows. Start your workouts with compound exercises since they are most effective at bringing about muscle gains. First choose an Olympic lift -- like hang cleans and push jerks; these are compound exercises that heavily involve muscles in your legs, hips and torso, but the muscles in your arms help guide the barbell. Next, add two to three compound exercises that work just the upper body. Choose from dips, close-grip pushups and close-grip bench presses, which work your chest and shoulders and challenge your triceps to straighten your arms and your forearms to stabilize your wrists. You can also include chinups and close-grip, underhand pulldowns, which recruit your latissimus dorsi in your back and place a significant load on your biceps and forearms.

Isolating the Arms
Once you’ve finished your compound lifts, move onto isolation exercises that specifically target your biceps, triceps and forearms. For your biceps, choose from barbell biceps curls, dumbbell biceps curls, cable curls and dumbbell incline curls. Focus on your triceps with lying barbell triceps extensions, overhead dumbbell triceps extensions and standing cable triceps pushdowns. During each biceps and triceps exercise, keep your elbows in a static position as you either straighten or bend them. Work your forearms with wrist curls, reverse wrist curls, hammer curls and wrist rollers.

Significance of Volume
Workouts designed for building muscle are different than ones that focus on developing strength. Muscle-building training requires high-volume workouts, which mean sessions should consist of numerous exercises that are done for multiple sets for a relatively high number of reps. Pete McCall of the American Council on Exercise recommends doing three to five sets of eight to 12 reps of every exercise and resting just 45 seconds in between each set. Use a weight that makes finishing the reps within each set challenging. For example, if you're unable to do eight reps, you should lighten the weight. If you can do more than 12 reps with relative ease, you should bump up the weight slightly.