Cable One Arm Tricep Extension

About This Exercise

The Cable One-Arm Tricep Extension is an isolation exercise that targets the triceps brachii muscle on the back of the upper arm. It is performed unilaterally (one arm at a time) using a cable machine, which provides constant tension throughout the range of motion. This exercise is useful for developing arm strength and definition, and for addressing muscular imbalances.

1Setup

1. Attach a single handle to the high pulley of a cable machine. 2. Stand facing the machine, feet roughly shoulder-width apart. You may stagger your stance for stability. 3. Grasp the handle with a supinated (underhand, palm facing up) grip using your right hand. 4. Step back to create tension in the cable, keeping your torso upright.

2Execution

1. Starting Position: Tuck your right elbow firmly into your side. Your upper arm should be vertical and your forearm should be raised, forming roughly a 90-degree angle at the elbow, with the handle near your shoulder. 2. Movement: Exhale and contract your triceps to extend your elbow, pulling the handle straight down until your arm is fully extended (but not hyperextended) at your side. Only your forearm should move. 3. Peak Contraction: Hold the extended position for a second, squeezing your triceps. 4. Return: Inhale and slowly allow the handle to return along the same path to the starting position, maintaining control against the weight. 5. Complete all repetitions for one arm before switching to the left.

Pro Tips

• Imagine your upper arm is a hinge fixed at your side; only your forearm should swing down.
• Avoid letting your elbow flare out or your shoulder shrug up during the movement.
• Squeeze your triceps hard at the bottom of the movement for a full contraction.
• Control the weight on the way up—don't let it yank your arm back into the start position.
• Keep your torso upright and avoid leaning into the movement to maintain isolation on the triceps.