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  3. Exercises
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  5. Core & Abs
  6. /
  7. Seated Single Leg Raise

Exercise guide

Seated Single Leg Raise

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

The Seated Single Leg Raise is a beginner-friendly isolation exercise that strengthens the hip flexors and quadriceps while engaging the lower abdominals for stability. It is particularly effective for improving knee health and core control through a controlled, unilateral range of motion.

Reviewed by the Crucible Fit team · Updated June 2026

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

Muscles worked

Primary

  • Abs
  • Quadriceps

Secondary

  • Glutes
  • Hip flexors

Equipment

  • Body weight

Setup

  1. Sit tall on the edge of a flat bench with your feet flat on the floor, hip-width apart.
  2. Grip the sides of the bench just behind your hips to stabilize your torso.
  3. Extend your target leg straight out in front of you with your heel lightly touching the floor.
  4. Engage your core and maintain a neutral spine with a very slight lean back for balance.

How to do it

  1. Exhale and lift your straightened leg upward toward the ceiling, keeping the knee fully locked.
  2. Raise the leg until it is at least parallel to the floor, or as high as your hip mobility allows without rounding your back.
  3. Inhale as you slowly lower the leg back to the starting position using a 2-second controlled tempo.
  4. Perform all repetitions on one side before switching to the opposite leg.

Form checklist

  • Keep the working knee completely straight throughout the entire set.
  • Maintain an upright chest and avoid slouching or rounding the lower back.
  • Ensure the stationary foot remains firmly planted on the ground for stability.
  • Avoid using momentum or 'swinging' the leg; keep the movement slow and deliberate.

Pro tips

  • Flex your toes toward your shin (dorsiflexion) to increase tension throughout the anterior chain.
  • Focus on a hard squeeze of the quadriceps at the top of the movement to maximize muscle fiber recruitment.
  • Imagine pulling your thigh bone into your hip socket to better engage the deep hip flexors and lower abs.

Make it harder

  • Add ankle weights to increase the resistance on the quadriceps and hip flexors.
  • Perform a 3-second isometric hold at the peak of the contraction on every rep.

Frequently asked

What muscles does the seated single leg raise work?
The seated single leg raise primarily targets the abs and quadriceps, and also works the glutes and hip flexors as secondary muscles.
What equipment do you need for the seated single leg raise?
The seated single leg raise requires no equipment — just your body weight.
Is the seated single leg raise good for beginners?
Yes. The seated single leg raise 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
  • Alternate Leg Lift TwistIntermediate · abs, obliques, and quadriceps
  • Alternating Hamstring Curl JackIntermediate · abs, 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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