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  5. Arms
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  7. Cable Concentration Extension On Knee

Exercise guide

Cable Concentration Extension On Knee

  • Intermediate
  • Isolation
  • Rep-based
  • Lower legs
  • Upper arms
  • Waist

This unilateral isolation exercise targets the triceps by using the inner thigh as a stabilizer to eliminate momentum and ensure peak contraction. The cable provides constant tension throughout the range of motion, making it highly effective for muscle hypertrophy and definition.

Reviewed by the Crucible Fit team · Updated June 2026

Watch the Cable Concentration Extension On Knee demonstrationVideo and instructions for every movement are in the Crucible Fit app.

Muscles worked

Primary

  • Triceps

Secondary

  • Abs
  • Obliques

Equipment

  • Cable

Setup

  1. Set the cable pulley to a low position and attach a single D-handle.
  2. Kneel on the floor perpendicular to the machine, placing the elbow of the working arm against the inside of the same-side thigh.
  3. Grasp the handle with a neutral grip, ensuring the cable is taut and your torso is slightly leaned forward.

How to do it

  1. Exhale as you extend your arm fully by contracting the triceps, keeping the upper arm stationary against your thigh.
  2. Squeeze the triceps at the point of full extension for a one-second pause.
  3. Inhale and slowly return the handle to the starting position over a 2-3 second count, maintaining tension.

Form checklist

  • Keep the elbow pinned firmly to the thigh to prevent the shoulder from assisting the movement.
  • Maintain a neutral wrist position throughout the range of motion to avoid forearm strain.
  • Ensure the torso remains still; do not rock your body or use momentum to move the weight.
  • Complete all reps on the weaker arm first to manage fatigue and ensure muscular symmetry.

Pro tips

  • At the peak of the contraction, try to 'push' your pinky finger toward the wall behind you to intensify the squeeze on the lateral head.
  • Use your non-working hand to touch the triceps of the working arm to enhance the mind-muscle connection.

Make it harder

  • Add a 2-second isometric hold at the point of maximum extension on every rep.
  • Perform slow-tempo eccentrics, taking 4-5 seconds to return to the starting position.

Frequently asked

What muscles does the cable concentration extension on knee work?
The cable concentration extension on knee primarily targets the triceps, and also works the abs and obliques as secondary muscles.
What equipment do you need for the cable concentration extension on knee?
The cable concentration extension on knee uses cable.
Is the cable concentration extension on knee good for beginners?
The cable concentration extension on knee is rated intermediate. Build a base with simpler variations first, then progress to it with light load and strict form.

Related exercises

  • Barbell Clean And PressAdvanced · deltoids, erector spinae, glutes, hamstrings, quadriceps, and triceps
  • Baseball HitAdvanced · biceps, deltoids, glutes, hamstrings, lats, obliques, pectorals, quadriceps, and triceps
  • Dumbbell BurpeeIntermediate · deltoids, glutes, hamstrings, pectorals, quadriceps, and triceps
  • Dumbbell Glute Bridge Skull CrusherIntermediate · glutes, hamstrings, and triceps

Train it with Crucible Fit.

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