Bicycle Crunches

Body Part: Core

Muscle: Obliques

Equipment: Body Weight

Bicycle Crunches are a bodyweight core exercise that combines a crunch, torso rotation, and alternating leg extension. The obliques are the main target, while the rectus abdominis and hip flexors help lift the torso and move the legs through the cycling pattern.

A clean bicycle crunch is slower and more deliberate than many people expect. The shoulder rotates toward the opposite knee while the other leg extends, but the hands stay light behind the head and the neck should not be pulled forward. The rotation should come from the rib cage, not just the elbow moving across the body.

Set up on your back with knees lifted, hands lightly behind the head, and lower back controlled. Rotate one shoulder toward the opposite knee as the other leg reaches out, then switch sides with the same control. Keep breathing and avoid letting the legs pull the lower back into an arch.

Use Bicycle Crunches as an oblique-focused core exercise, warmup, or finisher. They can be made easier by keeping the extended leg higher or moving more slowly. Quality rotation and trunk control matter more than fast rep counts.

Instructions

• Lie on your back with your hands lightly behind your head and elbows open.
• Lift your knees over your hips and brace your abs.
• Raise your shoulders slightly from the floor without pulling on your neck.
• Rotate one shoulder and elbow toward the opposite knee.
• Extend the other leg away from you at a height your lower back can control.
• Switch sides by rotating through the torso as the legs trade positions.
• Exhale during each twist toward the knee.
• Continue alternating with smooth, controlled reps.

Tips & Tricks

• Keep your hands light behind the head so the abs lift the torso.
• Think shoulder toward opposite knee, not elbow yanking across.
• Extend the leg higher if a low leg position arches your back.
• Move slowly enough that each side has a clear rotation.
• Keep the elbows wide instead of folding them around the head.
• Exhale on the twist to help the ribs rotate.
• Pause briefly if you start rushing the cycling pattern.
• Stop when neck tension replaces abdominal work.

Frequently Asked Questions

What muscles do bicycle crunches work?

They mainly work the obliques, with help from the abs and hip flexors.

Should I go fast?

Controlled reps are usually better than fast reps that lose rotation and core tension.

Why does my neck get tired?

You may be pulling on your head. Keep the hands light and let the torso do the work.

Should my elbow touch my knee?

It does not have to. Aim for controlled torso rotation toward the opposite knee.

Where should my lower back be?

Keep it controlled against the floor. Raise the extended leg higher if your back arches.

Can beginners do Bicycle Crunches?

Yes, but beginners should move slowly and keep the leg extension higher or shorter.

Are Bicycle Crunches good for obliques?

Yes. The cross-body rotation is a strong oblique-focused pattern when performed with control.

What is the biggest mistake?

Rushing through reps by pulling the head and barely rotating the torso.