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  7. Lying Lower Back Knee To Chest

Exercise guide

Lying Lower Back Knee To Chest

  • Beginner
  • Compound
  • Timed hold
  • Upper legs
  • Waist

This exercise gently stretches the glutes and lower back, improving hip mobility and relieving tension in the lumbar spine. It is an effective recovery or warm-up move for enhancing lower body flexibility and core stability.

Reviewed by the Crucible team · Updated June 2026

Watch the Lying Lower Back Knee To Chest demonstrationGuided video and your full workout live in the Crucible app.

Muscles worked

Primary

  • Abs
  • Obliques

Secondary

  • Erector spinae
  • Hip flexors

Equipment

  • Body weight

Setup

  1. Lie flat on your back on a mat with your legs fully extended.
  2. Place your arms at your sides and relax your head and shoulders against the floor.
  3. Maintain a neutral spine with your gaze directed toward the ceiling.

How to do it

  1. Exhale as you slowly pull one knee toward your chest, grasping your shin or the back of your thigh with both hands.
  2. Pull the knee as close to your torso as comfortable, holding the stretch for 2-3 seconds.
  3. Inhale as you slowly lower the leg back to the starting position with control.
  4. Repeat the movement with the opposite leg, alternating sides for the desired number of repetitions.

Form checklist

  • Keep the non-working leg pressed flat against the floor.
  • Ensure your head and neck remain relaxed on the mat throughout the movement.
  • Avoid holding your breath; time the pull with a deep exhale.
  • Keep your lower back in contact with the floor as you pull the knee in.

Pro tips

  • To deepen the stretch in the glute, pull the knee slightly outward toward your armpit rather than straight to the center of the chest.
  • Focus on 'heavy' hips, allowing your pelvis to sink into the floor to maximize the release in the lumbar region.

Make it harder

  • Perform a double-knee-to-chest tuck, pulling both legs in simultaneously to increase the stretch on the lower back.
  • Lift your forehead toward your knee at the peak of the movement to incorporate a gentle abdominal contraction.

Frequently asked

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

Related exercises

  • 45 Degrees Arms PlankIntermediate · abs, deltoids, obliques, and pectorals
  • 90 To 90Beginner · abs, glutes, obliques, and quadriceps
  • 90 To 90 SwitchIntermediate · abs, glutes, obliques, and quadriceps
  • Air BikeIntermediate · abs and obliques

Train this with a plan, not guesswork

Crucible builds the lying lower back knee to chest into a precise program around your body, equipment, location, and time.

Download on the App Store