If you’re looking to strengthen your rectus abdominus (AKA your six-pack muscles), as well as your obliques (the muscles on the sides of your abdominal wall), bicycle crunches are an excellent exercise. Crunches activate your abdominal muscles through lumbar flexion, which is flexing or rounding at the lower part of the spine. Bicycle crunches take it one step further by adding spinal rotation— this is the extra sauce that hits your obliques.

Although bicycle crunches are great for firing up your abs, many people do them incorrectly and focus too much on crunching movements in general, which can lead to back pain and injury. Including other core exercises in your workouts, such as deadbugs, Pallof presses, and loaded carries (farmer’s walks, for instance), is vital. These help build spinal stability and mobility for a strong, functional core.

How To Do Bicycle Crunches

To correctly perform a bicycle crunch, you must re-learn how to engage your abs before starting. Most people flex at the hips rather than the lumbar spine, which stresses the lower back and does not effectively activate the abs.

Start by laying on the floor and tilting your pelvis so your lower back (or sacrum) presses into the floor. Next, think about curling your chest toward your belly button (or the bottom of your ribcage toward the top of your pelvis) using your abdominals. These movements engage your abdominal muscles and protect your spine. 

1. From a lying position, with your abs engaged and lower back pressed into the floor, place your hands behind your head (without grabbing it) and raise your head and tops of your shoulder blades off the floor.
2. Lift your legs a few inches off the floor with a slight knee bend, maintaining your core engagement. This is the starting position.
3. Bring your left elbow to your right knee by rotating your torso while crunching your abdominals (think: chest toward belly button). Keep your left leg extended.
4. Reverse the motion, straightening your right leg back to the starting position.
5. Switch sides and repeat the motion using your right elbow and left knee.

Tip: Raise your legs higher at the starting position to make this slightly more manageable.

5 Bicycle Crunch Variations

Try these bicycle crunch variations for beginners, advanced, reduced mobility, and more.

Variation for Beginners: Supported Bicycle Crunches

Supported bicycle crunches make this movement easier by taking out the challenge of keeping your rectus abdominus curled and activated throughout the movement. Instead, this version focuses on the leg movement while keeping the torso still. This version is a great way to introduce yourself to bicycle crunches and works well for those who cannot yet support the weight of their upper body with their abdominal muscles.

1. Sit on the floor with your knees bent and lean back onto your forearms, elbows stacked under your shoulders.
2. Crunch your chest toward your belly button to engage your abdominals.
3. Extend your left leg, keeping it a couple of inches off the floor. Lift your right foot off the floor and pull your right knee toward your chest.
4. Slowly reverse the motion and repeat on the other side.

Tip: Make this even easier by resting your extended leg on the floor.

Advanced Variation: Weighted Bicycle Crunches

Adding resistance with weights is one of the easiest and most effective ways to increase the challenge of any core exercise. As with any resistance training movement, adding load provides an additional stimulus for the muscle fibers, boosting muscle growth. Progressing your ab exercises is often overlooked but is just as crucial for results as adding weight to the bar for movements such as squats and deadlifts.

1. Lie on your back with your abs engaged and lower back pressed into the floor. Hold a kettlebell or dumbbell in your hands at chest height and raise your head and the tops of your shoulder blades off the floor.
2. Lift your legs a few inches off the floor with a slight knee bend, maintaining your core engagement and holding the weight in front of you. This is the starting position.
3. Twist your left elbow to your right knee by rotating your torso and the weight while crunching your abdominals. Keep your left leg extended.
4. Reverse the motion, straightening your right leg back to the starting position.
5. Switch sides and repeat the motion using your right elbow and left knee.

Variation for Back Pain or Limited Mobility: Seated Bicycle Crunches

If you have limited mobility, are chair-bound, or have difficulty getting onto and off of the floor due to your weight, joint pain, back issues, or any other limitation, you can still perform a variation of bicycle crunches that work your rectus abdominus and obliques.

1. Sit upright in a firm, stable chair with your feet flat on the floor. Tilt your pelvis so your lower back is pressed against the back of the chair so your abdominals are engaged.
2. Bring your hands behind your head without grasping it, elbows out to the sides. 
3. Using your abdominal muscles, twist your torso to bring your right elbow toward your left knee. Think about curling your chest toward your belly button. Only rotate as far as you are comfortable.
4. Reverse the motion to return to the center and repeat on the other side.

Variation for Added Resistance: Banded Bicycle Crunches

Adding resistance by using a band on your feet increases the demand on your abdominals, requiring you to brace against the band’s pull. Perform these bicycle crunches slowly, controlling the movement instead of allowing the band to pull you.

1. Lie on your back with your abs engaged and lower back pressed into the floor with a band attached or looped around your ankles. Raise your head and the tops of your shoulder blades off the floor.
2. Lift your legs a few inches off the floor with a slight bend in your knees, maintaining your core engagement and feeling the pull of the band. This is the starting position.
3. Twist your left elbow to your right knee by rotating your torso while pulling the band toward you using your abs. Keep your left leg extended.
4. Reverse the motion, straightening your right leg back to the starting position while resisting the band’s pull.
5. Switch sides and repeat the motion using your right elbow and left leg.

Variation for Building Stability: Isohold Bicycle Crunches

Adding an isometric hold to your bicycle crunch will force you to work against gravity as your body rotates, pulling you from side to side. This bracing and stabilizing effort increases the demand for small internal core muscles that help keep your spine aligned and supported. Isometrics can also help recruit more motor units, producing more significant muscle-building effects. 

1. Lie on the floor holding a weight plate or dumbbell straight above your head, your abs engaged and lower back pressed into the floor. Raise your head and the tops of your shoulder blades off the floor, raising the weight straight upward.
2. Lift your legs a few inches off the floor with a slight knee bend, maintaining your core engagement. This is the starting position.
3. Rotate your torso while crunching your abdominals, keeping your elbows locked with the weight above you. Keep your left leg extended.
4. Reverse the motion, straightening your right leg back to the starting position.
5. Switch sides and repeat the motion.