4 x 4 Biceps Curls (How To, Muscles Worked, Benefits)

4 x 4s – the curl exercise, not the board – were actually first introduced to me by a player. He looked at me one day and said, “Coach, why don’t we ever do 4x4s?”

I had no clue what he was talking about, but when he explained the exercise to me I knew I’d never forget it.

In this guide, I’m going to teach you how to do 4x4s, including some important coaching tips and benefits.

How To Do 4 x 4s

Equipment Needed

Dumbbells

Muscles Worked

Biceps Brachii
Brachialis
Brachioradialis
Forearm Flexors

Step-by-Step Instructions

Grab two dumbbells and stand tall with feet shoulder-width apart.
Curl the left dumbbell halfway up, freezing it in place when the forearm becomes parallel to the ground.
Hold the left arm there while you do 4 regular dumbbell curls with the right arm.
Now, bring the left arm down and curl the right dumbbell up halfway and freeze it in place.
Hold the right arm there while you do 4 regular dumbbell curls with the left arm.
Now lower the right arm back down to the start.
Finally, do 4 regular dumbbell curls with both arms at the same time.

Coaching Points

It may take a set or two to figure out the proper weight to use for 4 x 4s. Start light and then gradually increase in weight until you find a good weight range for you.

Don’t rush through the movement! Part of the beauty of 4 x 4s is the isometric contraction of the arm being held in place halfway. If you simply try to get through the exercise as fast as possible you’re missing out on the intention of the exercise.

Keep the elbow at the side and don’t let it drift behind the torso. You can make the dumbbell much easier to hold up if you slide your elbow behind your torso. Don’t do that. Keep the elbow at your side and the dumbbell held out in front of you.

Benefits

Other than the normal benefits you would expect out of a biceps curl exercise, like increased strength and muscle mass, the biggest benefit comes from the isometric contraction.

Because you hold each arm in an isometric contraction while the other curls, you get a tremendous amount of time under tension. Time under tension, essentially how long you make the muscle work, is a key contributor to hypertrophy.

4 x 4 Alternatives

Looking for an alternative for 4 x 4s? Here are a few exercises you may be able to use as a substitution.

21s

21s is a similar biceps curl movement that involves partial movements and a ton of time under tension.

Use a barbell (or EZ curl bar) in place of dumbbells and start by curling halfway up 7 times. Now bring the bar to the shoulders and lower it halfway down 7 times. Finally, perform 7 full reps – all the way up and down.

Seated Alternating Dumbbell Curls

Seated Dumbbell Curl — Turn a Hammer Curl into a Regular Curl by simply turning the palm up as you curl.

Want something a little more… simple?

Ditch all the crazy partial reps and isometric contractions, sit down and do Seated Alternating Dumbbell Curls.

Sit at the edge of a bench and curl one arm at a time. By focusing on one arm at a time and because of the decreased overall time and tension, you’ll be able to use more weight and focus more on building pure strength.