Exercise guide
Dumbbell Lying One Arm Supinated Triceps Extension
- Intermediate
- Isolation
- Rep-based
- Chest
- Upper arms
This unilateral isolation exercise targets the triceps, specifically emphasizing the medial and lateral heads through a supinated grip. It helps correct muscle imbalances and allows for a greater range of motion compared to bilateral variations.
Reviewed by the Crucible team · Updated June 2026
Muscles worked
Setup
- Lie flat on a bench with your feet planted firmly on the floor for stability.
- Hold a dumbbell in one hand using a supinated (underhand) grip, so your palm is facing toward your head.
- Extend the arm straight up over your shoulder, positioning the dumbbell directly above your chest.
- Place your non-working hand on the bench or use it to lightly stabilize the upper arm of the working side.
How to do it
- Inhale and slowly lower the dumbbell toward your opposite shoulder by bending only at the elbow.
- Keep your upper arm stationary and perpendicular to the floor throughout the entire descent.
- Exhale as you contract the triceps to extend the arm back to the starting position, focusing on a controlled tempo.
- Complete the full set on one arm before switching to the other side.
Form checklist
- Keep the elbow tucked in and avoid letting it flare out to the side.
- Ensure only the forearm moves; the upper arm should remain vertical and still.
- Maintain a neutral wrist to avoid unnecessary strain during the supinated grip.
- Lower the weight under control to prevent the dumbbell from bouncing at the bottom.
Pro tips
- Slightly angle your upper arm back toward your head (about 10-15 degrees) to maintain constant tension on the triceps at the top of the rep.
- Focus on the mind-muscle connection by visualizing the triceps lengthening during the eccentric phase and shortening during the extension.
Make it harder
- Add a two-second pause at the bottom of the movement to eliminate momentum and increase difficulty.
- Perform 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 one arm supinated triceps extension work?
- The dumbbell lying one arm supinated triceps extension primarily targets the triceps, and also works the abs and obliques as secondary muscles.
- What equipment do you need for the dumbbell lying one arm supinated triceps extension?
- The dumbbell lying one arm supinated triceps extension uses dumbbell.
- Is the dumbbell lying one arm supinated triceps extension good for beginners?
- The dumbbell lying one arm supinated triceps extension is rated intermediate. Build a base with simpler variations first, then progress to it with light load and strict form.