Cable One Arm Tricep Side Extension
The Cable One Arm Tricep Side Extension is a unilateral isolation exercise performed on a cable machine that targets the outer portion of the upper arm. By extending the forearm across the body to the side, it isolates the lateral head of the triceps while correcting strength imbalances between arms.
Iridium uses this isolation movement to specifically target the lateral head of the triceps when your calculated adaptive volume requires direct work without the systemic fatigue of heavy pressing. The AI reviews your recent push training to ensure this exercise complements rather than duplicates fatigue from overhead or long-head dominant movements.
Form Cues
- Pin your elbow firmly against your ribcage
- Start with your forearm across your stomach
- Extend your arm fully out to the side
- Squeeze the tricep hard at the point of full extension
- Control the weight slowly as you return to the start
- Don't let your elbow drift away from your side
- Don't rotate your torso to help move the weight
- Don't use momentum or swing the handle
- Don't hunch your shoulder up toward your ear
Common Mistakes
- Moving the upper arm during the rep
- Twisting the body to generate force
- Cutting the range of motion short
- Using a weight that causes form breakdown
- Flaring the elbow out
Muscles Worked
This exercise places primary emphasis on the lateral head of the triceps brachii, which is responsible for the 'horseshoe' look of the arm. It also engages the medial head and forearm muscles for stability, offering a distinct angle of contraction compared to standard overhead or downward pressing movements.
Primary
Secondary
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