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  1. Home
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  3. Exercises
  4. /
  5. Core & Abs
  6. /
  7. Lying Alternating Crunch And Twist

Exercise guide

Lying Alternating Crunch And Twist

  • Beginner
  • Compound
  • Rep-based
  • Waist

This exercise targets the rectus abdominis and obliques by combining a standard crunch with trunk rotation, effectively building core stability and waistline definition.

Reviewed by the Crucible Fit team · Updated June 2026

Watch the Lying Alternating Crunch And Twist demonstrationVideo and instructions for every movement are in the Crucible Fit app.

Muscles worked

Primary

  • Abs
  • Obliques

Secondary

  • Erector spinae

Equipment

  • Body weight

Setup

  1. Lie flat on your back on a mat with your knees bent and feet flat on the floor, hip-width apart.
  2. Place your fingertips lightly behind your ears or head, keeping your elbows flared out wide.
  3. Tuck your chin slightly toward your chest to maintain a neutral neck position.
  4. Engage your core by pressing your lower back firmly into the floor.

How to do it

  1. Exhale as you lift your head and shoulders off the floor, rotating your torso to bring one shoulder toward the opposite knee.
  2. Focus on the rotation of the ribcage rather than just moving the elbow to maximize oblique engagement.
  3. Inhale as you slowly lower back to the starting position with a controlled tempo.
  4. Repeat the movement on the opposite side, alternating sides for each repetition.

Form checklist

  • Keep your lower back pressed into the mat to protect your spine.
  • Avoid pulling on your neck; your hands should only provide light support.
  • Keep your elbows wide and out of your peripheral vision to ensure the core does the work.
  • Maintain a steady, rhythmic breathing pattern throughout the set.

Pro tips

  • Imagine trying to touch your ribcage to the opposite hip bone to deepen the contraction.
  • Pause for a split second at the peak of the movement to emphasize the mind-muscle connection in the obliques.

Make it harder

  • Lift your feet off the floor into a tabletop position (90-degree bend) to increase the demand on the lower abs.
  • Extend the non-working leg straight out a few inches above the floor as you crunch toward the opposite side.

Frequently asked

What muscles does the lying alternating crunch and twist work?
The lying alternating crunch and twist primarily targets the abs and obliques, and also works the erector spinae as secondary muscles.
What equipment do you need for the lying alternating crunch and twist?
The lying alternating crunch and twist requires no equipment — just your body weight.
Is the lying alternating crunch and twist good for beginners?
Yes. The lying alternating crunch and twist 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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