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  1. Home
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  3. Exercises
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  5. Chest
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  7. Cable Kneeling Single Arm Fly

Exercise guide

Cable Kneeling Single Arm Fly

  • Intermediate
  • Isolation
  • Rep-based
  • Chest
  • Shoulders
  • Upper arms
  • Waist

This unilateral isolation exercise uses constant cable tension to target the pectorals and anterior deltoids while the kneeling position increases core stability and prevents momentum. It is highly effective for correcting muscle imbalances and achieving a deep peak contraction at the midline of the chest.

Reviewed by the Crucible Fit team · Updated June 2026

Watch the Cable Kneeling Single Arm Fly demonstrationVideo and instructions for every movement are in the Crucible Fit app.

Muscles worked

Primary

  • Pectorals

Secondary

  • Abs
  • Deltoids
  • Serratus anterior

Equipment

  • Cable

Setup

  1. Set the cable pulley to shoulder height and attach a D-handle.
  2. Kneel perpendicular to the machine in a half-kneeling position, with the leg closest to the machine forward for stability.
  3. Grasp the handle with the hand furthest from the machine using a neutral grip (palm facing forward).
  4. Position yourself far enough away so there is tension on the cable while your arm is extended to the side.

How to do it

  1. Maintain a slight bend in your elbow and exhale as you pull the handle across your body toward the midline of your chest in a wide arc.
  2. Squeeze your chest hard at the end of the movement, slightly crossing the midline of your body to maximize the contraction.
  3. Inhale as you slowly reverse the movement back to the starting position, resisting the weight to maintain control.
  4. Follow a controlled tempo, taking 2 seconds to reach the center and 3 seconds to return to the start.

Form checklist

  • Keep your torso upright and core braced to prevent the weight from rotating your hips.
  • Maintain a consistent 'soft' bend in the elbow throughout the entire range of motion.
  • Keep your shoulder blade retracted and depressed to ensure the chest, not the front delt, does the work.
  • Ensure the movement occurs only at the shoulder joint; do not turn it into a press.

Pro tips

  • Focus on bringing your inner bicep toward your sternum rather than just moving your hand to maximize pectoral shortening.
  • Place your non-working hand on the working pectoral muscle to enhance the mind-muscle connection and feel the fibers contracting.

Make it harder

  • Add a 2-second isometric hold at the point of maximum contraction across the midline.
  • Slow down the eccentric (return) phase to 5 seconds to increase time under tension.

Frequently asked

What muscles does the cable kneeling single arm fly work?
The cable kneeling single arm fly primarily targets the pectorals, and also works the abs, deltoids, and serratus anterior as secondary muscles.
What equipment do you need for the cable kneeling single arm fly?
The cable kneeling single arm fly uses cable.
Is the cable kneeling single arm fly good for beginners?
The cable kneeling single arm fly is rated intermediate. Build a base with simpler variations first, then progress to it with light load and strict form.

Related exercises

  • Air Punches MarchBeginner · calves, pectorals, and quadriceps
  • Alternate Front Kick In Place With Arm CirclesBeginner · abs, calves, deltoids, and pectorals
  • Archer Push-UpAdvanced · pectorals
  • Aztec Push UpIntermediate · pectorals, serratus anterior, and triceps

Train it with Crucible Fit.

Every movement in this library is in the app with video and instructions, ready for your own sessions on the days between Crucibles. Your first Crucible is on us.

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