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

Exercise guide

Side Lying Cycle Oblique Tuck

  • Intermediate
  • Compound
  • Rep-based
  • Waist

This exercise targets the obliques and hip flexors by combining a lateral crunch with a cycling leg motion, significantly improving core stability and side-waist definition.

Reviewed by the Crucible Fit team · Updated June 2026

Watch the Side Lying Cycle Oblique Tuck 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 on your right side with your legs extended and stacked on top of each other.
  2. Prop your upper body up on your right forearm, ensuring your elbow is directly under your shoulder.
  3. Place your left hand lightly behind your head with the elbow pointing toward the ceiling.
  4. Lift both legs slightly off the floor to engage your core before starting the movement.

How to do it

  1. Exhale as you pull your left knee toward your chest while simultaneously crunching your left elbow down to meet it.
  2. Inhale and extend your left leg back out in a circular 'pedaling' motion, keeping the foot hovering just above the floor.
  3. Maintain a controlled 2-1-2 tempo, focusing on the deep contraction of the side abdominals at the top of the tuck.
  4. Complete all repetitions on one side before switching to the left side.

Form checklist

  • Keep your chest open and avoid collapsing your shoulder into your neck.
  • Ensure the movement comes from your waist, not just moving your arm and leg.
  • Keep your hips stacked vertically; do not roll backward onto your glutes.
  • Maintain constant tension by never letting the working leg touch the ground.

Pro tips

  • Focus on the 'mind-muscle connection' by visualizing the space between your lower ribs and hip bone closing as you tuck.
  • Point your toes during the extension phase to maximize the engagement of the quadriceps and hip flexors.

Make it harder

  • Perform the movement from a full side plank position (supported by a straight arm) to increase the stability demand.
  • Wear ankle weights to increase the resistance on the obliques and hip flexors during the cycling phase.

Frequently asked

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