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  1. Home
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  3. Exercises
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  5. Core & Abs
  6. /
  7. Lying Cycle

Exercise guide

Lying Cycle

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

The Lying Cycle is a dynamic core exercise that targets the rectus abdominis and obliques through rotational movement while engaging the quadriceps and hip flexors. It is highly effective for building rotational strength and improving midsection definition.

Reviewed by the Crucible Fit team · Updated June 2026

Watch the Lying Cycle demonstrationVideo and instructions for every movement are in the Crucible Fit app.

Muscles worked

Primary

  • Abs
  • Obliques

Secondary

  • Glutes
  • Hip flexors

Equipment

  • Body weight

Setup

  1. Lie flat on your back on a mat with your lower back pressed firmly into the floor.
  2. Place your hands lightly behind your head with your elbows flared out wide.
  3. Lift your legs into a tabletop position with knees bent at 90 degrees and shins parallel to the floor.
  4. Engage your core to lift your shoulder blades slightly off the mat.

How to do it

  1. Simultaneously bring your right elbow toward your left knee while extending your right leg straight out at a 45-degree angle.
  2. Exhale as you rotate your torso, focusing on bringing the shoulder—not just the elbow—toward the opposite knee.
  3. Inhale as you switch sides in a fluid, controlled pedaling motion, bringing the left elbow toward the right knee.
  4. Continue alternating sides at a steady, rhythmic tempo while keeping the shoulder blades elevated.

Form checklist

  • Keep your lower back glued to the floor to protect the spine.
  • Rotate from the ribcage and obliques rather than pulling on your neck with your hands.
  • Keep your elbows wide and out of your peripheral vision throughout the movement.
  • Fully extend the straight leg to maximize the challenge to your lower abs and quads.

Pro tips

  • Focus on the 'armpit-to-knee' connection rather than 'elbow-to-knee' to ensure full thoracic rotation and maximum oblique engagement.
  • Slow down the movement to a 2-second count per side to eliminate momentum and increase time under tension.

Make it harder

  • Lower the extended leg so it hovers just an inch above the floor to increase the lever load on the lower abdominals.
  • Hold the peak contraction on each side for 2 seconds before switching.

Frequently asked

What muscles does the lying cycle work?
The lying cycle primarily targets the abs and obliques, and also works the glutes and hip flexors as secondary muscles.
What equipment do you need for the lying cycle?
The lying cycle requires no equipment — just your body weight.
Is the lying cycle good for beginners?
Yes. The lying cycle 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 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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