Cable single arm Biceps Hammer Curl
Exercise

Cable single arm Biceps Hammer Curl

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BicepsForearms
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Workout Center

The cable single-arm biceps hammer curl is a unilateral isolation exercise performed at a low cable pulley using a neutral, palm-in grip. Unlike free-weight hammer curls, the cable provides constant tension throughout the entire range of motion, including at full arm extension where dumbbells lose resistance. It primarily builds the biceps brachii and brachialis, with the neutral grip placing extra emphasis on the brachioradialis of the forearm, and working one arm at a time helps address strength imbalances.

Muscles Targeted

  • Primary: Biceps brachii, brachialis
  • Secondary: Brachioradialis (forearm)
  • Tertiary: Core and oblique stabilizers (resisting rotation)

Starting Position

Attach a single D-handle to a low pulley on a cable machine. Stand facing the machine with feet shoulder-width apart and a slight knee bend, holding the handle with a neutral grip (palm facing your torso) and your arm fully extended down by your side with the elbow lightly pinned to your ribs. Keep your torso upright and core braced so the cable pulls you slightly forward rather than sideways.

Execution Steps

  1. Set your elbow position against your side and take up the cable slack before starting the rep
  2. Curl the handle upward by flexing at the elbow only, keeping your upper arm stationary throughout
  3. Maintain the neutral grip with your palm facing inward the entire way up, avoiding any rotation of the wrist
  4. Bring the handle toward your shoulder, squeezing the biceps hard at the top of the movement
  5. Lower the handle under control, resisting the cable's pull back to full elbow extension
  6. Complete all reps on one arm before switching sides, keeping tension constant throughout the set

Form Cues

  • Pin the elbow: Keep it locked against your torso for the entire rep to isolate the biceps
  • Don't rotate the wrist: The hammer grip stays neutral throughout, unlike a standard curl
  • Resist the urge to swing: Keep your torso still and avoid using your hips to help initiate the curl
  • Control the eccentric phase actively rather than letting the cable snap your arm back down
  • Stand close enough to the pulley that the cable path stays roughly vertical through the rep

Common Mistakes

  • Swinging the torso for momentum: This shifts work away from the biceps and can strain the lower back. Keep your core braced and torso stationary.
  • Letting the elbow drift forward: This turns the movement into a shoulder-assisted curl and reduces biceps isolation. Keep the elbow fixed at your side.
  • Not achieving full extension at the bottom: Stopping short shortens the range of motion and reduces the stretch stimulus. Let the arm fully straighten each rep.
  • Rushing the eccentric: Letting the cable pull the arm back quickly wastes a major portion of the muscle-building stimulus. Lower for at least 2-3 seconds.
  • Standing too far from the pulley: This changes the cable angle and reduces tension at the top or bottom of the movement. Stay close enough for a mostly vertical cable path.

Variations

  • Rope cable hammer curl: Using a rope attachment lets you train both arms simultaneously with the same neutral grip
  • Double cable hammer curl: Attaching two single handles allows a bilateral version for greater total load
  • Standing dumbbell hammer curl: A free-weight alternative without constant cable tension, useful when a cable station is unavailable
  • Seated single-arm cable curl: Removes lower-body movement, increasing strictness and isolation
  • Cross-body cable curl: Curling the handle toward the opposite shoulder shifts emphasis and engages the obliques for stability

Tips for Progression

  • Add weight in small 2.5-5 pound increments once you can complete all sets with full range of motion
  • Build up to 12-15 reps per arm before adding load
  • Add a 1-2 second pause at peak contraction to increase time under tension
  • Slow the eccentric to 3-4 seconds to increase overall training volume without adding weight

Training Notes

Include this exercise on arm or upper-body days 2-3 times per week as an isolation finisher after compound pulling movements like rows or pull-ups. Work in the 10-12 rep range per arm for 3-4 sets, resting 45-60 seconds between sets and sides. The unilateral setup makes it particularly useful for correcting left-right strength imbalances in the biceps and forearms.

Exercise Details

Body Parts
Biceps, Forearms
Category
Workout Center

Frequently Asked Questions

How often should I do the Cable single arm Biceps Hammer Curl?

Because the Cable single arm Biceps Hammer Curl works biceps, forearms, two to three sessions a week is a sensible range for most people. Leave at least a day between sessions that hammer biceps so the tissue can recover and adapt. If you train it harder, do it less often.

Is the Cable single arm Biceps Hammer Curl suitable for beginners?

Yes. The Cable single arm Biceps Hammer Curl is rated beginner-friendly, so it is a solid starting point. Start light, nail the technique, and only add load once the pattern feels automatic. New to lifting? A coach can check your setup in a single session.

What should I do if the Cable single arm Biceps Hammer Curl causes pain?

Stop the set right away. A working burn in biceps is fine, but sharp or pinching pain is a signal, not a challenge. Reset your cable setup, drop the weight, and if the pain comes back, talk to a physio or certified trainer before your next session.

How much weight should I use for the Cable single arm Biceps Hammer Curl?

Pick a load you can move with clean form for every planned rep, where only the last one or two feel genuinely hard. Since this is a pulling movement, let your back and arms drive the work rather than yanking with momentum. When form holds across all sets, nudge the load up a little.

Can I modify the Cable single arm Biceps Hammer Curl?

Plenty of options exist. You can swap the cable for something similar, shorten the range of motion while you learn the groove, or change your stance to shift the emphasis around biceps, forearms. Single-joint moves like this one also work well as a finisher after heavier lifts. Adjust to fit your body, not the other way round.