Exercise guide
Dumbbell Standing One Arm Extension
- Intermediate
- Isolation
- Rep-based
- Shoulders
- Upper arms
This unilateral isolation exercise targets the triceps, specifically the long head, by utilizing an overhead position to provide a deep stretch and focused contraction. It is highly effective for correcting muscle imbalances and improving overhead stability.
Reviewed by the Crucible team · Updated June 2026
Muscles worked
Setup
- Stand with your feet shoulder-width apart and engage your core to stabilize your spine.
- Hold a dumbbell in one hand and extend your arm straight up toward the ceiling.
- Position your elbow close to your ear, pointing it forward or slightly outward.
- Place your non-working hand on your waist or across your torso for balance.
How to do it
- Inhale and slowly lower the dumbbell behind your head by hinging only at the elbow while keeping the upper arm stationary.
- Lower the weight until your forearm is at least parallel to the floor or you feel a deep stretch in the triceps.
- Exhale and contract the triceps to drive the weight back up to the starting position.
- Maintain a controlled 2-0-2 tempo, ensuring no momentum is used at the bottom of the lift.
Form checklist
- Keep the upper arm vertical and locked in place; only the forearm should move.
- Avoid arching your lower back; keep your ribs tucked and glutes squeezed.
- Ensure your head remains neutral and is not pushed forward by your working arm.
- Do not allow the elbow to flare out excessively to the side during the descent.
Pro tips
- Focus on the 'stretch' at the bottom of the movement to maximize recruitment of the triceps' long head.
- Use your non-working hand to lightly touch the working triceps to enhance the mind-muscle connection.
Make it harder
- Add a 2-second pause at the bottom of each repetition to eliminate the stretch reflex.
- Perform the exercise while standing on one leg (opposite to the working arm) to increase the core stability demand.
Frequently asked
- What muscles does the dumbbell standing one arm extension work?
- The dumbbell standing one arm extension primarily targets the triceps, and also works the deltoids and forearms as secondary muscles.
- What equipment do you need for the dumbbell standing one arm extension?
- The dumbbell standing one arm extension uses dumbbell.
- Is the dumbbell standing one arm extension good for beginners?
- The dumbbell standing one arm extension is rated intermediate. Build a base with simpler variations first, then progress to it with light load and strict form.