Biceps curls are a valuable training exercise for those looking to build bigger arms. They're an isolation exercise, which means they only involve movement around a single joint and don't work many muscle groups. They're designed for targeting the small collection of muscles at the front of your upper arms that are responsible for bending your elbows. Most biceps curls primarily work the biceps brachii, the largest and strongest of the elbow flexor muscles.

Despite their effectiveness for building arm size, biceps curls can be boring. Luckily, there are various ways to do them if you feel the need to change up your routine.

A common mistake when performing biceps curls is to use a weight that is too heavy, which causes a lifter to rock back and forth in an effort to utilize momentum. If you finish that you're jerking your body to complete a rep, it's time to lighten the load.

Dumbbell or Barbell Standing Curls

The traditional biceps curl exercise is typically performed while standing and with a pair of dumbbells or a single barbell. You'll find you can likely lift more overall weight when using a barbell, but the advantage of dumbbells is that they force each arm to work independently rather than the dominant one handling a majority of the load. You can also perform them on a cable pulley unit with straight bar attachment.

To perform the traditional biceps curl, stand while holding your weight of choice with your arms down by your sides. If you're using a barbell or a straight bar attached to a cable pulley unit, grip the bar with hands set to shoulder-width and palms facing forward. Bend your elbows to curl the weight up to your shoulders. Straighten your arms to lower the weight back down and finish the rep.

Hammer Curls

Hammer curls primarily target the brachioradialis muscle that runs down the inside of your upper and lower arm. Lifters will often incorporate hammer curls into their regimen when they're interested in building tone or size throughout the entire arm. Hammer curls must be completed with dumbbells.

Stand or sit while holding a dumbbell in each hand. Begin with the weights down by your sides with palms facing in toward your thighs. While maintaining your wrist position and keeping your elbows close to your sides, bend your arms to curl the dumbbells up to your shoulders. Straighten your arms to lower the weights back to the starting position. Repeat until you're finished with all the reps.

To change it up, you can perform alternating hammer curls and raise one weight at a time.

Dumbbell Concentration Curls

Concentration curls are among the most effective exercises for specifically isolating the biceps brachii muscle. The exercise involves working one arm at a time, and the arm is stabilized against the thigh.

Sit down on a flat bench with your legs spread and feet flat on the floor. Hold a single dumbbell in one hand. Let the weight hang down in between your thighs. With your arm fully extended, place the back of your upper arm against the inside of the inside of the same-side thigh. Rotate your wrist so that your palm is facing away from your leg. Keeping the upper arm against the thigh, bend your elbow to curl the weight up toward your shoulder. Extend your elbow to straighten your arm and lower the dumbbell back toward the floor. Repeat until you've finished all reps and then switch arms.

Lying Cable Curls

The lying curl is a more advanced biceps exercise and appropriate for lifters looking to add workout variety. You'll need a flat bench and a cable pulley unit with either a straight or E-Z bar attached.

Position the bench so that it's perpendicular to the pulley unit. Set the pulley so that it's positioned just higher than the height of the bench. Lie on your back on the bench with your feet closest to the pulley. Grip the bar with hands positioned shoulder-width apart, your arms extended beside your torso and palms facing upward. Keep your elbows close to your body as you bend them to curl the bar up to your chest. Slowly extend your elbows to return the bar back to the starting position and to complete one rep. Repeat until you've finished with all the assigned reps.

You can also do reverse lying cable curls by flipping your grip on the bar so that your palms begin facing the floor.


The 21's exercise is common among lifters looking to build mass or significant tone in their arms. They're often done at the very end of a workout because they leave the biceps fatigued. They can be done with any type of equipment - dumbbells, a barbell, a cable pulley unit, or on a biceps curl machine.

Every set of 21's has three parts. You begin with seven reps of curling the weight up from your thighs to when your arms are parallel to the floor and back down again. Then, begin with your forearms parallel to the floor and curl the weight all the way up to your shoulders and back to parallel for seven reps. Finally, perform seven reps of full-range biceps curls. In the end, you'll have finished 21 reps, and that is considered one set. If you do multiple sets, rest 120 to 150 seconds in between each one.