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  3. Exercises
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  5. Core & Abs
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  7. Bicycle Crunch

Exercise guide

Bicycle Crunch

  • Intermediate
  • Compound
  • Rep-based
  • Waist

The bicycle crunch is a premier core exercise that targets the rectus abdominis and obliques by combining spinal flexion with trunk rotation. It is highly effective for developing rotational stability and deep abdominal definition through a coordinated, alternating movement.

Reviewed by the Crucible Fit team · Updated June 2026

Watch the Bicycle Crunch demonstrationVideo and instructions for every movement are in the Crucible Fit app.

Muscles worked

Primary

  • Abs
  • Obliques

Secondary

  • Serratus anterior

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 fingertips lightly behind your ears or the base of your skull, keeping 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. Lift your shoulder blades slightly off the ground to create initial tension in the upper abdominals.

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 forcefully 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 motion, bringing the left elbow toward the right knee while extending the left leg.
  4. Continue alternating sides in a rhythmic 'pedaling' motion, maintaining a slow and steady tempo to avoid using momentum.

Form checklist

  • Keep your lower back glued to the floor throughout the entire set to protect the spine.
  • Avoid pulling on your neck with your hands; use your core to lift and rotate the torso.
  • Ensure the extended leg stays straight and hovers just above the floor for maximum tension.
  • Keep your elbows wide and out of your peripheral vision to force the obliques to do the work.

Pro tips

  • Focus on the 'mind-muscle connection' by visualizing your ribcage rotating toward your opposite hip bone.
  • Slow down the movement significantly; a 2-second hold at the peak of each rotation will dramatically increase muscle fiber recruitment.

Make it harder

  • Perform the movement with straight legs (Scissor Crunches) to increase the lever length and demand on the lower abs.
  • Pause for 3 seconds at the point of peak contraction on every repetition.

Frequently asked

What muscles does the bicycle crunch work?
The bicycle crunch primarily targets the abs and obliques, and also works the serratus anterior as secondary muscles.
What equipment do you need for the bicycle crunch?
The bicycle crunch requires no equipment — just your body weight.
Is the bicycle crunch good for beginners?
The bicycle 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 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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