One-Arm Standing DB Extension

Illustration of a man performing standing single arm tricep extension with dumbbell, showing the starting phase on the left and the finishing phase on the right, with highlighted muscles.

Exercise Description

The One-Arm Standing Dumbbell Triceps Extension is an isolation exercise that targets the triceps one arm at a time. By performing the movement unilaterally, it helps improve muscular balance, coordination, and mind-muscle connection while placing significant emphasis on the long head of the triceps. The standing position also challenges core stability and shoulder control throughout the exercise.

Primary Muscles Worked

  • Triceps Brachii (Long Head, Lateral Head, and Medial Head)

Secondary Muscles Worked

  • Anconeus

  • Anterior Deltoids (Stabilization)

  • Rotator Cuff Muscles (Stabilizers)

  • Upper Trapezius

  • Rectus Abdominis

  • Obliques

  • Erector Spinae (Lower Back Stabilizers)

How to Perform Correctly

Setup

  1. Stand upright holding a dumbbell in one hand.

  2. Press the dumbbell overhead until your arm is fully extended.

  3. Position your feet shoulder-width apart.

  4. Engage your core and maintain a neutral spine.

  5. Keep your elbow close to your head and pointing upward.

Movement

  1. Slowly lower the dumbbell behind your head by bending your elbow.

  2. Keep your upper arm stationary throughout the movement.

  3. Lower the weight until you feel a comfortable stretch in your triceps.

  4. Pause briefly at the bottom position.

  5. Extend your elbow and raise the dumbbell back to the starting position.

  6. Squeeze your triceps at the top of the movement.

  7. Complete all repetitions on one arm before switching sides, or alternate arms as desired.

Common Mistakes to Avoid

Allowing the Elbow to Flare Out

  • Keep the elbow close to your head to maximize triceps activation and maintain proper mechanics.

Using Excessive Weight

  • Heavy weights often lead to poor technique and reduced range of motion.

Moving the Upper Arm

  • Only the forearm should move during the exercise.

Arching the Lower Back

  • Engage your core and glutes to maintain a stable, neutral spine.

Using Momentum

  • Avoid leaning or swinging your body to assist the lift.

Incomplete Range of Motion

  • Lower the dumbbell fully under control and extend the elbow completely at the top.

Lowering the Weight Too Quickly

  • Control the descent to improve muscle engagement and reduce injury risk.

Arm Exercises