Also known as: air bike, air bicycle, bike crunches, bicycle sit-ups, bicycle abs

What is Bicycle Crunches?

Bicycle crunches are a bodyweight abdominal exercise that combines a crunch with alternating knee-to-elbow twists to target the rectus abdominis and obliques. They improve core stability and rotational control. Difficulty: easy - suitable for beginners when performed with controlled tempo and a flat lower back to protect the spine.

How to Do Bicycle Crunches

  1. Start position: Lie flat with lower back pressed to the floor, knees bent, feet on the ground, hands lightly behind head; brace your core before moving.
  2. Lift knees: Lift knees to a 90-degree angle and raise feet off the floor, keeping shoulder blades elevated and neck neutral; engage your core to protect the spine.
  3. Pedal motion: Extend one leg straight while drawing the opposite knee toward your chest; move slowly, initiating rotation from the ribs and core rather than the neck.
  4. Elbow-to-knee: Rotate your torso and bring the opposite elbow toward the raised knee, exhaling on the twist; keep the motion controlled and avoid jerking.
  5. Alternate sides: Switch sides in a steady, controlled rhythm, keeping hips level and both legs elevated; maintain tension in the core to prevent lower-back arching.
  6. Finish safely: Slowly lower feet and shoulders back to the floor, release tension, reset lumbar contact with the ground, and breathe deeply; stop if you feel pain.

Muscle Groups

Core

Description

Lie flat on the floor with your lower back pressed to the ground and knees bent. Your feet should be on the floor and your hands are behind your head. Contract your core muscles, drawing in your abdomen to stabilise your spine.

With your hands gently holding your head, pull your shoulder blades back and slowly raise your knees to about a 90-degree angle, lifting your feet from the floor.

Exhale and slowly, at first, go through a bicycle pedal motion, bringing one knee up towards your armpit while straightening the other leg, keeping both elevated higher than your hips.

Rotate your torso so you can touch your elbow to the opposite knee as it comes up.

Alternate to twist to the other side while drawing that knee towards your armpit and the other leg extended until your elbow touches the alternate knee.

Repeat for the required amount of repetition for each side.
Movement Group: Core
Equipment: None (bodyweight only)

Progressions and Regressions

None

Frequently Asked Questions

What are the benefits of bicycle crunches?

Bicycle crunches strengthen the rectus abdominis and obliques, improving core stability, rotational control, and posture. They require no equipment and help build endurance and coordination when performed with proper tempo and form.

What are common mistakes with bicycle crunches?

Common errors include pulling on the neck, using momentum instead of core engagement, letting the lower back arch, and dropping legs too low. These mistakes reduce effectiveness and increase spinal strain—focus on slow, controlled movements.

How can I progress or regress bicycle crunches?

To progress, increase tempo control, add a light weight behind the head, decline the bench, or try slow eccentric reps. To regress, perform bent-leg marches, standing bicycle taps, or reduce range of motion while maintaining core bracing.