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  3. Exercises
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  5. Core & Abs
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  7. Oblique Crunches With Straight Leg Lift

Exercise guide

Oblique Crunches With Straight Leg Lift

  • Intermediate
  • Compound
  • Rep-based
  • Waist

This compound core exercise targets the obliques and adductors by combining lateral trunk flexion with a straight leg lift, enhancing lateral stability and hip strength.

Reviewed by the Crucible Fit team · Updated June 2026

Watch the Oblique Crunches With Straight Leg Lift demonstrationVideo and instructions for every movement are in the Crucible Fit app.

Muscles worked

Primary

  • Abs
  • Adductors
  • Obliques

Secondary

  • Erector spinae

Equipment

  • Body weight

Setup

  1. Lie on your side with your legs stacked and perfectly straight.
  2. Place your bottom arm flat on the floor in front of you for balance and your top hand lightly behind your head.
  3. Engage your core to maintain a straight line from your head to your feet.

How to do it

  1. Exhale as you lift your top leg toward the ceiling while simultaneously crunching your upper torso toward your hip.
  2. Focus on bringing your elbow toward your thigh, feeling the squeeze in your side.
  3. Inhale as you slowly lower your leg and torso back to the start position with a controlled 2-second tempo.
  4. Perform all repetitions on one side before switching to the other.

Form checklist

  • Keep your top leg locked straight to maximize adductor and hip engagement.
  • Avoid pulling on your head; use your core to lift your shoulders.
  • Maintain a strictly lateral movement without rolling your hips forward or backward.
  • Keep your neck neutral and aligned with your spine.

Pro tips

  • Think about shortening the distance between your lower ribs and your hip bone for maximum oblique activation.
  • Keep your toes pointed forward rather than up to keep the tension on the lateral chain and glute medius.

Make it harder

  • Lift both legs together (Double Side Leg Lift Crunch) to significantly increase the demand on the obliques.
  • Add a 2-second pause at the top of each rep to increase time under tension.

Frequently asked

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

Related exercises

  • Criss Cross Leg RaisesIntermediate · abs, adductors, and obliques
  • Front Plank To Toe TapIntermediate · abs, adductors, erector spinae, hamstrings, obliques, pectorals, and trapezius
  • Kneeling Forward Hip CirclesBeginner · abs, adductors, erector spinae, glutes, hip flexors, and obliques
  • Lying Abduction Leg Raise On FloorIntermediate · abs, adductors, and obliques

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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