Bicycle Crunch
The bicycle crunch is a bodyweight exercise that targets the abdominal muscles with a strong emphasis on the obliques. The alternating rotation and leg extension mimic a cycling motion, making it one of the most effective core exercises for muscle activation.
How to do it
- Lie flat on your back with your hands placed lightly behind your head and legs lifted off the ground.
- Bend your right knee toward your chest while simultaneously rotating your left elbow toward it.
- Extend your right leg and bring your left knee in, rotating your right elbow toward the left knee.
- Continue alternating sides in a smooth pedaling and twisting motion.
- Repeat for the desired number of repetitions.
Form cues
- Keep your lower back pressed flat against the floor throughout the movement.
- Rotate from your ribcage rather than pulling on your neck with your hands.
- Move in a slow, controlled rhythm rather than rushing through the reps.
- Breathe out steadily as you twist and touch your elbow toward the knee.
Breathing: Exhale as you twist toward your knee, and inhale as you switch sides in the center.
Common mistakes
- Pulling on the neck with the hands, which strains the cervical spine instead of working the abs.
- Arching the lower back off the floor, which reduces core engagement and can cause discomfort.
- Moving too fast and using momentum rather than muscle control to cycle the legs.
Muscles worked
Primary: abs. Secondary: obliques, hip flexors.
Suggested sets & reps
Get fitter
3 sets × 12–15 reps per side, rest 60 s
Lose weight
3 sets × 15–20 reps per side, rest 45 s
Build muscle
3 sets × 10–15 reps per side, rest 60 s
Easier, harder & alternatives
Make it harder
Take care if…
- If you feel sharp neck or lower back discomfort, ease off and rest.
General educational guidance, not medical advice. Stop on sharp pain and check with a qualified professional if unsure.
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Start free →Frequently asked questions
Should my neck hurt during bicycle crunches?
No. If your neck aches, you are likely pulling your head with your hands. Support your head lightly and focus on lifting your shoulders using your upper abs.
How can I stop my lower back from arching?
Keep your core braced and consciously press your lower back into the floor. If it lifts, try keeping your legs higher in the air.
How often can I do bicycle crunches?
You can include them 2 to 3 times per week as part of your regular core or full-body routine.