Exercise guide
Cable Alternate Triceps Extension
- Intermediate
- Isolation
- Rep-based
- Shoulders
- Upper arms
This isolation exercise targets all three heads of the triceps, using an alternating unilateral approach to correct muscle imbalances and ensure symmetrical arm development.
Reviewed by the Crucible Fit team · Updated June 2026
Muscles worked
Setup
- Set the cable pulley to the highest position and attach a single D-handle.
- Stand facing the machine with feet shoulder-width apart and a slight bend in the knees for stability.
- Grasp the handle with your right hand using an overhand (palms down) grip.
- Position your elbow tucked firmly against your side with the forearm parallel to the floor.
How to do it
- Exhale as you push the handle down by extending the elbow until the arm is fully straight.
- Squeeze the triceps hard at the bottom of the movement for a one-second peak contraction.
- Inhale and slowly return the weight to the starting position using a controlled 2-3 second tempo.
- Switch the handle to your left hand and repeat the movement to complete one alternating repetition.
Form checklist
- Keep your upper arm stationary and pinned to your ribcage throughout the entire set.
- Maintain a tall posture with your core engaged to prevent leaning forward or using body weight.
- Ensure the movement occurs only at the elbow joint, avoiding any shoulder swinging.
- Keep your wrist straight and firm to maximize force transfer directly to the triceps.
Pro tips
- Imagine there is a pin through your elbow holding it in place against your side to ensure perfect isolation.
- At the bottom of the rep, slightly rotate your wrist outward (supination) to further engage the lateral head of the triceps.
Make it harder
- Incorporate a 3-second isometric hold at the point of peak contraction (full extension) on every rep.
- Perform the movement with a thumbless grip to increase the demand on triceps stability and focus.
Frequently asked
- What muscles does the cable alternate triceps extension work?
- The cable alternate triceps extension primarily targets the triceps, and also works the biceps and forearms as secondary muscles.
- What equipment do you need for the cable alternate triceps extension?
- The cable alternate triceps extension uses cable.
- Is the cable alternate triceps extension good for beginners?
- The cable alternate triceps extension is rated intermediate. Build a base with simpler variations first, then progress to it with light load and strict form.