Dumbbell Skull Crusher
The dumbbell skull crusher is a triceps isolation exercise performed lying on a bench. By lowering the dumbbells toward the temples with controlled elbow flexion, it provides a deep stretch and full contraction of the triceps, making it highly effective for arm development.
How to do it
- Lie flat on a bench holding a dumbbell in each hand with arms extended directly above your chest.
- Keeping your upper arms perpendicular to the floor, bend your elbows to lower the dumbbells toward your temples.
- Pause just above your head, then extend your arms back to the starting position.
- Keep your elbows pointed at the ceiling throughout the movement.
- Repeat for the desired number of repetitions.
Form cues
- Keep your upper arms completely still.
- Lower the weights slowly toward your temples.
- Point your elbows straight at the ceiling.
- Press the dumbbells back up using only your triceps.
Breathing: Inhale as you slowly lower the dumbbells toward your head, and exhale as you press them back up to the starting position.
Common mistakes
- Moving your upper arms back and forth uses your shoulders and reduces the load on your triceps.
- Flaring your elbows out to the sides shifts the work away from your triceps and stresses your shoulder joints.
- Using momentum to swing the weights up makes the exercise less effective and increases joint strain.
Muscles worked
Primary: triceps. Secondary: shoulders, forearms.
Suggested sets & reps
Get fitter
3 sets x 10-12 reps, rest 60-90 seconds
Lose weight
3 sets x 12-15 reps, rest 60 seconds
Build muscle
3-4 sets x 8-12 reps, rest 90 seconds
Easier, harder & alternatives
Make it easier
Take care if…
- If you feel sharp elbow discomfort, ease off and choose a gentler triceps movement.
General educational guidance, not medical advice. Stop on sharp pain and check with a qualified professional if unsure.
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Start free →Frequently asked questions
Why is it called a skull crusher?
It gets its name from the traditional barbell version where the weight is lowered toward the forehead. Using dumbbells allows you to lower them safely beside your head instead.
I feel this in my elbows. Is that normal?
Mild joint awareness can happen, but sharp or persistent pain in the elbow joint means you should lower the weight, reduce your range of motion, or choose a different triceps exercise.
How often can I do skull crushers?
1 to 3 times per week, depending on your overall workout routine, allowing at least 48 hours of recovery between arm sessions.