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  3. Exercises
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  5. Legs
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  7. Lever Seated One Leg Curl

Exercise guide

Lever Seated One Leg Curl

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

This unilateral isolation exercise targets the hamstrings individually, allowing for focused muscle activation and the correction of strength imbalances. The seated position provides maximum stability, ensuring the hamstrings perform the bulk of the work through knee flexion.

Reviewed by the Crucible Fit team · Updated June 2026

Watch the Lever Seated One Leg Curl demonstrationVideo and instructions for every movement are in the Crucible Fit app.

Muscles worked

Primary

  • Hamstrings

Secondary

  • Abs
  • Obliques

Equipment

  • Leverage machine

Setup

  1. Adjust the backrest so your knee aligns perfectly with the machine's pivot point.
  2. Position the lower roller pad just above your heel, against the lower Achilles tendon of the working leg.
  3. Lower the thigh stabilization pad firmly against your lap to prevent your hips from lifting during the movement.
  4. Grip the side handles to stabilize your upper body and keep your glutes pressed into the seat.

How to do it

  1. Exhale as you curl the weight downward by flexing your knee as far as comfortably possible toward the seat.
  2. Squeeze your hamstring hard at the bottom of the movement for a one-second peak contraction.
  3. Inhale as you slowly return the weight to the starting position, maintaining controlled tension throughout the ascent.
  4. Complete all repetitions on one leg before switching to the other side to ensure equal volume.

Form checklist

  • Keep your lower back pressed firmly against the backrest throughout the set.
  • Ensure the working knee stays aligned with the machine's axis of rotation.
  • Avoid using momentum or 'kicking' the weight down; focus on a smooth, controlled pull.
  • Keep your non-working leg relaxed and stationary on the floor or footrest.

Pro tips

  • Keep your toes pointed toward your shin (dorsiflexion) to maximize hamstring tension and minimize calf involvement.
  • Focus on pulling your heel directly toward the underside of the seat to maximize the shortening of the hamstring fibers.

Make it harder

  • Implement a 3-4 second slow eccentric (negative) phase to increase time under tension.
  • Add a 3-second isometric hold at the point of maximum contraction on every rep.

Frequently asked

What muscles does the lever seated one leg curl work?
The lever seated one leg curl primarily targets the hamstrings, and also works the abs and obliques as secondary muscles.
What equipment do you need for the lever seated one leg curl?
The lever seated one leg curl uses leverage machine.
Is the lever seated one leg curl good for beginners?
The lever seated one leg curl is rated intermediate. Build a base with simpler variations first, then progress to it with light load and strict form.

Related exercises

  • 3 Point Standing HopsIntermediate · calves, glutes, hamstrings, and quadriceps
  • 4 Cone Single Foot Lateral HopsIntermediate · calves, glutes, hamstrings, and quadriceps
  • 4 Way Single Leg HopAdvanced · calves, glutes, hamstrings, and quadriceps
  • Air Pillow Balance Counterbalanced Skater SquatAdvanced · glutes, hamstrings, and quadriceps

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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