Dumbbell Skull Crusher

Dumbbell Skull Crushers

Are you looking for a simple and effective dumbbell exercise to inflate the back of your upper arms?

If so, the dumbbell skull crusher is a great option. The exercise is relatively easy to learn, develops the triceps, and provides decent overload, even for advanced trainees.

Read on to learn more about the exercise, including how to do it, what useful variations you can pick from, and how to combine it with other movements.

What Are Dumbbell Skull Crushers?

Despite its unsettling name, the dumbbell skull crusher is a safe and effective exercise. The skull crusher is an isolation exercise that works around a single joint (the elbow) and emphasizes one muscle group (the tricep).

Other muscles with a role in skull crushers include:

  • Midsection (abs, obliques, etc.) that provides stability
  • Shoulders (deltoids) for stability

The traditional way to perform the exercise is by using a pair of dumbbells on a flat gym bench.

Here are step-by-step instructions:

  1. Grab a pair of light dumbbells and lie on a flat gym bench.
  2. Extend your arms and position the dumbbells above your shoulders with your palms facing as you hold the dumbbells.
  3. Retract your shoulder blades, take a deep breath, and engage your abs.
  4. Slowly bend your elbows to bring the dumbbells to the sides of your head.
    NOTE: Try to imagine your elbows are fixed on a hinge.
  5. Pause for a moment and straighten your arms back to the start position as you exhale.

Dumbbell Skull Crushers | Variations

1. Bench

The classic way to perform skull crushers is to lie on a flat gym bench. You can also lie on a slight incline of roughly 30 degrees.

2. Floor

This variation is identical to bench skull crushers. The only difference is that you’re lying on the floor.

3. Single-Arm

Single-arm skull crushers are a variation where you train one arm at a time. The variation makes it easier to focus on one muscle at a time, and it works great if you only have one dumbbell. (1)

Skull Crushers With EZ Bars

You can also perform skull crushers with EZ bars:
Skull Crushers With EZ Bars

Exercises to Combine With Skull Crushers

Dumbbell skull crushers can work great with a variety of other chest exercises, including:

For example, if you’re at a gym, you can do the following:

  • Close-grip bench press
  • Cable tricep extensions
  • Dumbbell skull crushers

If you’re at home, you can do the following:

  • Bench/chair dips
  • Diamond push-ups
  • Dumbbell skull crushers

Safety And Final Thoughts

Like any other exercise, start with lighter weights and progress from there. It takes time to master proper form, and using heavy dumbbells can cause you to ingrain poor motor patterns. (2)

Additionally, maintain a solid grip on the dumbbells at all times. Doing so is vital for keeping yourself safe. The weights will be directly overhead multiple times per set, and you wouldn’t want to drop one on your face.

Finally, we have a technique tip that promotes safety and better muscle activation. Specifically, you should strive to extend the dumbbells away from your head. Do so by bringing your elbows to the sides of your head at the start of the set. As you extend your arms, the dumbbells won’t be directly over your face.

In addition to keeping the weights away from your face, this technique tweak can make it easier to stretch the long tricep head, leading to better activation and potentially more growth.

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Philip Stefanov

Philip is a fitness writer, blogger, certified personal trainer, and the founder of ThinkingLifter.com. He has spent the last nine years writing fitness content and training men and women in the gym, as well as online. His passion is fitness and exercise, and helping others improve their fitness and wellness.

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  1. Single-arm Skull Crusher – muscles worked, how-to, benefits. Fitness Volt. (2022, June 15).
  2. Nick. (2022, August 22). Build muscle and strength: Is lifting heavy weights better? U.P Blog.

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