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  5. Legs
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  7. Barbell Single Leg Squat

Exercise guide

Barbell Single Leg Squat

  • Advanced
  • Compound
  • Rep-based
  • Lower legs
  • Upper legs

This advanced unilateral movement builds exceptional lower-body strength, balance, and core stability by forcing the quadriceps and glutes to manage the entire load independently. It effectively addresses muscle imbalances while demanding high levels of ankle and hip mobility.

Reviewed by the Crucible Fit team · Updated June 2026

Watch the Barbell Single Leg Squat demonstrationVideo and instructions for every movement are in the Crucible Fit app.

Muscles worked

Primary

  • Calves
  • Glutes
  • Hamstrings
  • Quadriceps

Secondary

  • Abs
  • Obliques

Equipment

  • Barbell

Setup

  1. Position a barbell across your upper trapezius in a high-bar position, gripping the bar firmly with hands just wider than shoulders.
  2. Stand with feet hip-width apart, then shift your weight entirely onto your starting leg.
  3. Lift the non-working leg slightly off the floor in front of you, keeping it straight to act as a counterweight.
  4. Engage your core and fix your gaze on a point 5-10 feet ahead on the floor to maintain balance.

How to do it

  1. Inhale and begin the descent by sitting your hips back and bending the working knee, keeping the non-working leg extended forward.
  2. Lower yourself under control until your thigh is at least parallel to the floor, ensuring your standing heel remains firmly planted.
  3. Exhale and drive forcefully through the mid-foot of the standing leg to return to the starting upright position.
  4. Maintain a controlled 3-0-1-0 tempo (3 seconds down, no pause, 1 second up).

Form checklist

  • Keep the heel of the working foot glued to the floor throughout the entire rep.
  • Ensure the knee of the working leg tracks in line with your toes, avoiding any inward collapse.
  • Maintain a proud chest and neutral spine to prevent the barbell from shifting your center of mass too far forward.
  • Keep the non-working leg elevated and clear of the ground during the full range of motion.

Pro tips

  • Active Foot: 'Root' your foot into the ground by spreading your toes and gripping the floor to create a stable arch and better balance.
  • Upper Body Tension: Pull the barbell down into your traps to create 'irradiation,' which stabilizes the spine and makes the heavy load feel more integrated with your lower body.

Make it harder

  • Add a 2-second isometric pause at the bottom of the squat to eliminate momentum and maximize glute recruitment.
  • Increase the range of motion by performing the squat while standing on a small wooden block or weight plate.

Frequently asked

What muscles does the barbell single leg squat work?
The barbell single leg squat primarily targets the calves, glutes, hamstrings, and quadriceps, and also works the abs and obliques as secondary muscles.
What equipment do you need for the barbell single leg squat?
The barbell single leg squat uses barbell.
Is the barbell single leg squat good for beginners?
The barbell single leg squat is rated advanced. 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
  • Alternate Knee Cross Over Sit Against WallIntermediate · calves, 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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