How To Do Dumbbell Skull Crushers, The Ultimate Triceps Burner

When you think about arm workouts, you might imagine bicep curls or bench presses, but if you want to specifically target your triceps (the back of the upper arm) there’s one move, in particular, you’ll definitely want to remember: skull crushers.

This simple exercise requires only one dumbbell, and it’s as effective as it is quick—plus you can adjust the weight of the dumbbell to suit any skill level.

Here’s how to do it, as demonstrated by personal trainer and holistic nutritionist BB Arrington, CPT, who tells mbg skull crushers are an excellent strengthening move that will make pulling and extending movements easier.

How to do skull crushers:

1. Lie on your back with feet planted on the floor.
2. With dumbbells in hand, extend your arms to the ceiling.
3. Bending from the elbow, lower the weight to your forehead.
4. Extend the arm back to the ceiling to complete the rep. (Note: Upper arm should remain perpendicular to the floor the entire time.)
5. That’s one rep. Complete 8 to 12 reps.

Form tips

With skull crushers, your upper arms should remain perpendicular to the floor the entire time for proper form and to prevent shoulder injuries. Hold them still and move only from the elbow. And be sure to keep your low back pressing into the mat and engage your core to prevent arching in the low back.

Hug your elbows in, keeping them (and your wrists) shoulder distance apart. You can use a strap around the upper arms here to assist with that.

If you want to make this move easier, decrease the weight of your dumbbells—and increase the weight to make it more challenging.

Modifications & variations.

Skull crushers can be performed lying on your back on a weight bench, which allows you to lower your arms a bit farther toward the ground. You can also use an incline bench.

And again, you can adjust the weight of your dumbbell as needed to make this move easier or harder.

Alternatively, if you’re looking to work your triceps but you don’t have a dumbbell handy, try one of these exercises:

Chair Pose Triceps Kickback

1. Start in a standing position. Hold a pair of dumbbells in your hands, and bring them in front of your chest, palms facing in.
2. Sit your hips back, bend your knees, and lower down into chair pose.
3. Engage your triceps as you press the weights behind your body until your arms are fully extended.
4. With control, return back to start.

Tabletop Triceps Pushup

1. Start on all fours in a tabletop position. Stack shoulders right on top of the hands and hips right over knees.
2. Keep your elbows pointed toward your knees. Inhale as you bend the elbows and bring your chest toward the floor. Go as far down as you can; try to line your nose up with your fingertips.
3. Engage your core, and slowly lift your chest back up to start. Keep your chest open, but don’t arch your back.

Single-Leg Tabletop Triceps Pushup

1. Start on all fours, in a tabletop position. Stack the shoulders right on top of the hands, and your hips right over your knees.
2. Extend one leg out, keeping it at hip height. Be sure the hips stay parallel. Keep your elbows pointed toward your knees.
3. Inhale as you bend your elbows and bring your chest toward the floor. Go as far down as you can; try to line your nose up with your fingertips. Press the opposite shin into the ground.
4. Engage your core, and slowly lift your chest back up to start. Keep your chest open, but don’t arch your back.

The bottom line.

If you want to give your triceps some extra attention on arm day, this is definitely an exercise worth trying.