Lying Bicycle Crunch

Body Part: Waist

Muscle: Glutes

Equipment: Body Weight

Lying Bicycle Crunch is a floor-based abdominal exercise that combines a crunch with a controlled pedaling leg motion. It is designed to train the rectus abdominis, obliques, and hip flexors through a repeated cross-body pattern that keeps the torso slightly curled while the legs alternate in the air. The movement looks simple, but the quality of each rep depends on how well you keep the rib cage, pelvis, and neck organized.

The setup matters because the exercise works best when the lower back stays close to the floor and the shoulders remain lightly lifted. Lie on your back, place one knee in toward the chest, and extend the other leg without letting the lumbar spine arch. Hands should support the head without pulling on it, and the elbows should stay wide enough that the neck can remain relaxed. If the starting position is sloppy, the hips and lower back usually take over before the abs can.

Each rep should feel like a small, deliberate twist rather than a fast leg swing. Rotate the torso so the opposite elbow moves toward the raised knee while the other leg extends long and low. Then switch sides smoothly, keeping the shoulder blades hovering and the motion continuous. The goal is not to touch elbow to knee at all costs; the goal is to keep the trunk curled and the pelvis steady while alternating sides with control.

This exercise is useful in ab circuits, conditioning blocks, warmups, or as accessory work after heavier compound lifting. It is also a practical option for beginners because the movement can be shortened and slowed down easily. Keep the range of motion honest, breathe through the twist, and stop the set once the neck starts pulling, the lower back lifts, or the legs begin to swing instead of pedal. Clean reps with a controlled tempo will train the trunk far better than rushed repetitions.

Instructions

• Lie on your back with your lower back pressed into the floor and your knees bent over your hips.
• Lift your shoulders and head off the floor, and place your hands lightly behind your head with your elbows open.
• Bring one knee in toward your chest and extend the other leg long without letting your low back arch.
• Rotate your rib cage so the opposite elbow moves toward the raised knee.
• Keep the hovering leg low and controlled instead of letting it drift down to the floor.
• Switch sides in a smooth pedaling motion, alternating the elbow-to-knee twist each rep.
• Exhale as you twist and inhale as you pass through the center of the movement.
• Lower your shoulders and legs only when the set is finished and your trunk stays in control.

Tips & Tricks

• Think about bringing your ribs toward the opposite hip, not forcing your elbow to the knee.
• Keep the chin gently tucked and avoid jutting the head forward as fatigue builds.
• Let the hands support the skull only; if you pull on the neck, the abs usually lose the job.
• Straighten the moving leg only as far as you can keep the low back heavy on the floor.
• Keep the nonworking leg active and low instead of dropping it loosely and resting between reps.
• A slower switch between sides makes the obliques work harder and reduces leg momentum.
• If your lower back lifts, shorten the extension on both legs before trying more reps.
• Breathe out during the twist and keep the abs tight through the center position.

Frequently Asked Questions

What muscle does Lying Bicycle Crunch target most?

It mainly targets the rectus abdominis and obliques, with the hip flexors helping during the leg drive.

Should my lower back stay on the floor the whole time?

Yes. Keep the lumbar spine pressed down as much as possible so the abs do the work instead of the lower back.

How high should my shoulders be?

Just high enough to keep the shoulder blades off the floor. If you curl too high, the neck usually takes over.

Do I need to touch elbow to knee?

No. Aim for a strong cross-body crunch, but keep the movement smooth and controlled instead of chasing contact.

Why does my neck get tired on this exercise?

Usually because the head is being pulled forward. Keep the hands light and keep your gaze up rather than tucking hard.

Is this exercise good for beginners?

Yes, if you shorten the leg extension and move slowly. Beginners should focus on control before increasing speed.

What is the biggest form mistake?

Letting the legs swing while the torso rests. The best reps keep the trunk curled and the switches deliberate.

How can I make it harder without adding weight?

Slow the alternating switch, extend the legs a little lower, or add a brief pause at each twist while keeping the low back down.