Exercise guide
Dumbbell Seated Single Arm Overhead Triceps Extension Left
- Beginner
- Isolation
- Rep-based
- Shoulders
- Upper arms
This isolation exercise specifically targets the long head of the triceps by placing the muscle in a fully stretched position overhead. Performing it unilaterally allows for a greater range of motion and helps correct strength imbalances between arms.
Reviewed by the Crucible team · Updated June 2026
Muscles worked
Setup
- Sit upright on a flat bench with your feet planted firmly on the floor for stability.
- Hold a dumbbell in your left hand and extend your arm straight up toward the ceiling.
- Rotate your wrist so your palm faces inward (neutral grip) and tuck your left elbow close to your ear.
- Place your right hand on your waist or use it to lightly support your left upper arm to keep it vertical.
How to do it
- Inhale and slowly lower the dumbbell behind your head by bending only at the elbow, keeping your upper arm completely stationary.
- Lower the weight until your forearm is at least parallel to the floor or you feel a deep stretch in your triceps.
- Exhale as you contract your triceps to extend your arm back to the starting position, avoiding locking out the elbow aggressively.
- Maintain a controlled tempo, taking roughly two seconds to lower the weight and one second to press it back up.
Form checklist
- Keep your left elbow pointing forward or slightly inward; do not let it flare out to the side.
- Ensure only your forearm moves; your upper arm should remain perpendicular to the floor throughout.
- Keep your core tight and your back flat against an imaginary wall to avoid arching your spine.
- Maintain a neutral neck position, looking straight ahead rather than down at the floor.
Pro tips
- Focus on the deep stretch at the bottom of the movement, as this is where the long head of the triceps is most active.
- Use your right hand to feel the left triceps contracting to enhance the mind-muscle connection.
Make it harder
- Slow down the eccentric (lowering) phase to 3-4 seconds to increase time under tension.
- Add a one-second pause at the bottom of the rep to eliminate momentum and force the muscle to work harder from a dead stop.
Frequently asked
- What muscles does the dumbbell seated single arm overhead triceps extension left work?
- The dumbbell seated single arm overhead triceps extension left primarily targets the triceps, and also works the abs and obliques as secondary muscles.
- What equipment do you need for the dumbbell seated single arm overhead triceps extension left?
- The dumbbell seated single arm overhead triceps extension left uses dumbbell.
- Is the dumbbell seated single arm overhead triceps extension left good for beginners?
- Yes. The dumbbell seated single arm overhead triceps extension left is a beginner-friendly movement and a strong foundation to build on.