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  7. Leg Raise Oblique Crunch

Exercise guide

Leg Raise Oblique Crunch

  • Intermediate
  • Compound
  • Rep-based
  • Waist

This unilateral core exercise combines a lateral leg raise with a side crunch to intensely target the obliques, hip flexors, and abductors. It is highly effective for developing lateral trunk stability and defining the waistline.

Reviewed by the Crucible team · Updated June 2026

Watch the Leg Raise Oblique Crunch demonstrationGuided video and your full workout live in the Crucible app.

Muscles worked

Primary

  • Abs
  • Obliques

Secondary

  • Erector spinae

Equipment

  • Body weight

Setup

  1. Lie on your side on a mat with your legs stacked and perfectly straight.
  2. Place your bottom arm flat on the floor in front of you for balance, and place your top hand lightly behind your head.
  3. Engage your core to create a straight line from head to heels, slightly angling your legs forward to help maintain balance.

How to do it

  1. Exhale as you simultaneously lift your top leg and crunch your upper torso sideways, bringing your elbow toward your hip.
  2. Squeeze your obliques hard at the peak of the movement, ensuring your ribcage moves toward your pelvis.
  3. Inhale as you slowly lower your leg and torso back to the starting position with a 2-second eccentric tempo.
  4. Perform all repetitions on one side before switching to the other side.

Form checklist

  • Avoid pulling on your neck with your hand; use your obliques to lift your chest.
  • Keep your top leg straight and toes pointed to maximize hip and quad engagement.
  • Ensure you are moving laterally (sideways) rather than rolling onto your back.
  • Maintain constant tension by not letting your feet or shoulders fully rest on the floor between reps.

Pro tips

  • Visualize 'closing the gap' between your lower ribs and your hip bone to maximize oblique fiber recruitment.
  • Press your bottom palm lightly into the floor to stabilize your torso, but don't use it to push yourself up.

Make it harder

  • Lift both legs simultaneously while crunching to significantly increase the weight load on the lateral core.
  • Add a pause at the top of each rep for 2-3 seconds to eliminate momentum and increase time under tension.

Frequently asked

What muscles does the leg raise oblique crunch work?
The leg raise oblique crunch primarily targets the abs and obliques, and also works the erector spinae as secondary muscles.
What equipment do you need for the leg raise oblique crunch?
The leg raise oblique crunch requires no equipment — just your body weight.
Is the leg raise oblique crunch good for beginners?
The leg raise oblique crunch is rated intermediate. Build a base with simpler variations first, then progress to it with light load and strict form.

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 this with a plan, not guesswork

Crucible builds the leg raise oblique crunch into a precise program around your body, equipment, location, and time.

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