Exercise guide
Dumbbell Seated Bench Extension
- Intermediate
- Isolation
- Rep-based
- Chest
- Upper arms
This isolation movement targets all three heads of the triceps, with a specific emphasis on the long head due to the overhead arm position. It provides a deep stretch at the bottom of the movement, which is highly effective for muscle growth and overhead stability.
Reviewed by the Crucible Fit team · Updated June 2026
Muscles worked
Setup
- Sit upright on the end of a flat bench with your feet firmly planted on the floor for stability.
- Grasp a single dumbbell with both hands, forming a diamond shape with your palms against the underside of the top weight plate.
- Lift the dumbbell directly overhead until your arms are fully extended, keeping your chest up and shoulders down.
How to do it
- Inhale as you slowly lower the dumbbell behind your head by bending only at the elbows, keeping your upper arms vertical and tucked close to your ears.
- Lower the weight in a controlled manner until your forearms reach at least parallel to the floor or you feel a deep stretch in the triceps.
- Exhale as you drive the weight back up to the starting position by extending your elbows, following a 2-0-2 tempo.
Form checklist
- Keep your elbows pointed forward rather than flaring them out to the sides.
- Maintain a neutral spine and avoid excessively arching your lower back to compensate for the weight.
- Ensure your upper arms remain stationary throughout the movement; only the forearms should move.
- Keep your core braced to prevent your ribcage from flaring upward.
Pro tips
- Pause for one second at the bottom of the rep to maximize the stretch on the long head of the triceps.
- Focus on squeezing the triceps hard at the top of the movement without locking out the elbows aggressively.
Make it harder
- Increase the time under tension by using a 4-second eccentric (lowering) phase.
- Transition to a unilateral (one-arm) variation to increase the stability requirement and address muscle imbalances.
Frequently asked
- What muscles does the dumbbell seated bench extension work?
- The dumbbell seated bench extension primarily targets the triceps, and also works the abs and obliques as secondary muscles.
- What equipment do you need for the dumbbell seated bench extension?
- The dumbbell seated bench extension uses dumbbell.
- Is the dumbbell seated bench extension good for beginners?
- The dumbbell seated bench extension is rated intermediate. Build a base with simpler variations first, then progress to it with light load and strict form.