Exercise guide
Dumbbell Lying Triceps Extension Skull Crusher
- Beginner
- Isolation
- Rep-based
- Chest
- Upper arms
This isolation exercise targets all three heads of the triceps, with a particular emphasis on the long head by stretching it under load. Using dumbbells allows for a neutral grip, which reduces strain on the wrists and elbows compared to a barbell.
Reviewed by the Crucible team · Updated June 2026
Muscles worked
Setup
- Lie flat on a bench with your feet firmly planted on the floor for stability.
- Hold a dumbbell in each hand using a neutral grip (palms facing each other).
- Extend your arms straight up over your shoulders, then tilt your upper arms back about 15 degrees toward your head to maintain constant tension.
How to do it
- Inhale and slowly lower the dumbbells by bending only at the elbows until the weights are positioned near your temples.
- Keep your upper arms stationary and elbows tucked in throughout the entire descent.
- Exhale as you use your triceps to extend your arms back to the starting position.
- Maintain a controlled tempo, taking roughly two seconds to lower the weights and one second to extend.
Form checklist
- Keep your elbows pointing straight ahead; do not let them flare out to the sides.
- Ensure the movement occurs only at the elbow joint, keeping the shoulders pinned and stable.
- Maintain a neutral wrist position to avoid unnecessary strain.
- Lower the weights under full control to avoid momentum or injury.
Pro tips
- Keep your upper arms angled slightly back toward your head rather than perfectly vertical to keep the triceps engaged even at the top of the rep.
- Focus on the 'mind-muscle connection' by imagining you are pushing the weights away using only the back of your arms.
Make it harder
- Perform the movement with a 3-4 second eccentric (lowering) phase to increase time under tension.
- Execute the exercise on a slight decline bench to increase the stretch on the long head of the triceps.
Frequently asked
- What muscles does the dumbbell lying triceps extension skull crusher work?
- The dumbbell lying triceps extension skull crusher primarily targets the triceps, and also works the abs and obliques as secondary muscles.
- What equipment do you need for the dumbbell lying triceps extension skull crusher?
- The dumbbell lying triceps extension skull crusher uses dumbbell.
- Is the dumbbell lying triceps extension skull crusher good for beginners?
- Yes. The dumbbell lying triceps extension skull crusher is a beginner-friendly movement and a strong foundation to build on.