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  1. Home
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  3. Exercises
  4. /
  5. Core & Abs
  6. /
  7. Lying Single Leg Raise

Exercise guide

Lying Single Leg Raise

  • Beginner
  • Isolation
  • Rep-based
  • Waist

The Lying Single Leg Raise is a foundational core exercise that targets the lower abdominals and hip flexors while providing more stability for the lower back than double leg variations.

Reviewed by the Crucible Fit team · Updated June 2026

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

Muscles worked

Primary

  • Abs

Secondary

  • Obliques

Equipment

  • Body weight

Setup

  1. Lie flat on your back on a mat with both legs fully extended.
  2. Place your hands palms-down by your sides or tucked slightly under your glutes for extra lumbar support.
  3. Bend one knee and place that foot flat on the floor to stabilize your pelvis and protect your lower back.

How to do it

  1. Exhale and engage your core to lift the straight leg toward the ceiling until it is roughly perpendicular to the floor.
  2. Inhale and slowly lower the leg back down with a controlled 2-3 second tempo.
  3. Stop the descent just before your heel touches the floor to maintain constant tension on the abdominals.
  4. Complete the desired repetitions on one side before switching to the opposite leg.

Form checklist

  • Keep your lower back pressed firmly into the floor throughout the entire movement.
  • Ensure the knee of the working leg remains locked or only slightly soft.
  • Avoid using momentum; the movement should be slow and deliberate.
  • Keep your head and shoulders relaxed on the mat to avoid neck strain.

Pro tips

  • Focus on the mind-muscle connection by imagining your lower abs pulling your thigh toward your torso.
  • Flex your foot (toes toward shin) to keep the leg muscles engaged and stable during the lift.

Make it harder

  • Keep the non-working leg straight and hovering two inches off the floor instead of bending the knee.
  • Perform the movement with ankle weights to increase the load on the hip flexors and abdominals.

Frequently asked

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

Related exercises

  • 3/4 Sit-UpBeginner · abs and obliques
  • 45 Degree Bicycle Twisting CrunchIntermediate · abs and obliques
  • 45 Degree Lean Back Alternate Knee RaiseBeginner · abs and obliques
  • 45 Degrees Arms PlankIntermediate · abs, deltoids, obliques, and pectorals

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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