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  7. Lying Single Leg Extension

Exercise guide

Lying Single Leg Extension

  • Beginner
  • Compound
  • Rep-based
  • Lower legs
  • Upper legs
  • Waist

This exercise isolates the hamstrings and calves through prone hip extension, emphasizing the posterior chain's ability to stabilize and lift the leg without knee flexion.

Reviewed by the Crucible team · Updated June 2026

Watch the Lying Single Leg Extension demonstrationGuided video and your full workout live in the Crucible app.

Muscles worked

Primary

  • Quadriceps

Secondary

  • Abs
  • Hip flexors

Equipment

  • Body weight

Setup

  1. Lie face down (prone) on a flat, comfortable surface or exercise mat.
  2. Extend both legs straight behind you with your feet hip-width apart.
  3. Rest your forehead on your stacked hands or keep your arms at your sides for stability.
  4. Engage your core by pulling your belly button away from the floor to protect your lower back.

How to do it

  1. Exhale as you lift one leg off the floor, keeping the knee completely locked and the leg straight.
  2. Point your toes (plantarflexion) throughout the movement to maximize calf and hamstring tension.
  3. Lift the leg only as high as you can without tilting your pelvis or arching your lower back.
  4. Inhale as you slowly lower the leg back to the starting position with a controlled 2-second tempo.

Form checklist

  • Keep your hip bones (ASIS) in contact with the floor at all times.
  • Ensure the movement comes from the hip, not by bending the knee.
  • Maintain a neutral neck by looking straight down at the mat.
  • Keep your toes pointed to ensure the calves remain active throughout the set.

Pro tips

  • Focus on 'lengthening' the leg toward the back wall as you lift to increase hamstring recruitment.
  • Pause for a one-second squeeze at the top of the movement to maximize the mind-muscle connection in the upper hamstring.

Make it harder

  • Perform the movement with a 3-second eccentric (lowering) phase to increase time under tension.
  • Add a small pulse at the top of the range of motion before lowering the leg.

Frequently asked

What muscles does the lying single leg extension work?
The lying single leg extension primarily targets the quadriceps, and also works the abs and hip flexors as secondary muscles.
What equipment do you need for the lying single leg extension?
The lying single leg extension requires no equipment — just your body weight.
Is the lying single leg extension good for beginners?
Yes. The lying single leg extension is a beginner-friendly movement and a strong foundation to build on.

Related exercises

  • 90 To 90Beginner · abs, glutes, obliques, and quadriceps
  • 90 To 90 SwitchIntermediate · abs, glutes, obliques, and quadriceps
  • Air Punches MarchBeginner · calves, pectorals, and quadriceps
  • All Fours Squat StretchBeginner · quadriceps

Train this with a plan, not guesswork

Crucible builds the lying single leg extension into a precise program around your body, equipment, location, and time.

Download on the App Store