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  5. Legs
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  7. Hack One Leg Calf Raise

Exercise guide

Hack One Leg Calf Raise

  • Intermediate
  • Isolation
  • Rep-based
  • Lower legs

This unilateral variation isolates the gastrocnemius and soleus while using the hack machine's fixed path for stability, allowing for a greater range of motion and focused muscle fiber recruitment. By training one leg at a time, you can correct strength imbalances and achieve a deeper mind-muscle connection.

Reviewed by the Crucible Fit team · Updated June 2026

Watch the Hack One Leg Calf Raise demonstrationVideo and instructions for every movement are in the Crucible Fit app.

Muscles worked

Primary

  • Calves

Secondary

  • Glutes
  • Hamstrings
  • Quadriceps

Equipment

  • Leverage machine

Setup

  1. Position yourself in the hack squat machine with your shoulders firmly against the pads and your back flat against the backrest.
  2. Place the ball of your working foot on the edge of the footplate, ensuring the heel is hanging off the edge.
  3. Lift the non-working leg off the platform, bending the knee slightly so the foot is clear of the plate.
  4. Disengage the safety handles and stand tall to support the weight entirely on the working leg.

How to do it

  1. Inhale as you slowly lower your heel as far as possible below the level of the footplate to achieve a deep stretch in the calf.
  2. Exhale as you push through the ball of your foot to raise your heel as high as possible into a full contraction.
  3. Maintain a controlled 2-second descent and a 1-second pause at the top of the movement.
  4. Complete all reps on one side before switching to the other leg to ensure equal volume.

Form checklist

  • Keep your hips and back pressed firmly against the machine padding throughout the set.
  • Maintain a slight micro-bend in the knee to protect the joint and keep tension on the muscle.
  • Avoid bouncing at the bottom of the movement; use a controlled transition from stretch to contraction.
  • Ensure the ball of the foot is centered and secure on the platform to prevent slipping.

Pro tips

  • Focus on pushing specifically through the big toe to maximize activation of the medial head of the gastrocnemius.
  • Imagine you are trying to stand on your tiptoes as high as possible to achieve a peak cramp-like contraction at the top.

Make it harder

  • Add a 3-second pause at the bottom of the stretch to eliminate momentum and the stretch-reflex.
  • Implement '1.5 reps' by performing a full rep followed by a half-rep from the bottom to the midpoint.

Frequently asked

What muscles does the hack one leg calf raise work?
The hack one leg calf raise primarily targets the calves, and also works the glutes, hamstrings, and quadriceps as secondary muscles.
What equipment do you need for the hack one leg calf raise?
The hack one leg calf raise uses leverage machine.
Is the hack one leg calf raise good for beginners?
The hack one leg calf raise 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 Single Leg BalanceIntermediate · abs, calves, and obliques

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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