Reverse Crunch

Body Part: Waist

Muscle: Abs

Equipment: Body Weight

Reverse Crunch is a floor-based bodyweight core exercise that emphasizes curling the pelvis toward the ribs instead of swinging the legs. The image shows a lifter lying on the back with the knees bent and the thighs raised, then lifting the hips off the floor in a short, controlled arc. That makes this movement different from a regular crunch or leg raise: the rep should begin with the abs initiating a posterior pelvic tilt, not with momentum from the legs.

The main training effect is on the rectus abdominis, with the obliques and deep abdominal wall helping keep the torso stable while the pelvis rolls upward. The hip flexors assist to hold the legs in position, but if they dominate the set the lower back usually starts to arch and the hips stop curling cleanly. The goal is to keep the ribs down, pelvis tucked, and the lower back controlled against the floor through the whole rep.

Setup matters because the floor gives you a fixed reference point. Lie on your back, press the upper back and arms into the ground for support, and keep the knees bent so the shins stay roughly parallel to the floor. From that starting position, the motion should be small and deliberate: curl the tailbone up, lift the hips just enough to stack them slightly, then lower without letting the feet crash or the low back take over.

This exercise is useful when you want direct abdominal work without loading the spine with a machine or external weight. It works well in beginner core training, accessory blocks, warmups, and controlled abdominal finishers, especially when the athlete needs to learn how to posteriorly tilt the pelvis. The set should feel crisp and repeatable, not explosive. If the lower back arches, the knees drift, or the shoulders start to lift, the rep is too big or too fast.

Done well, Reverse Crunch builds better control of trunk position and helps teach the abs to finish the curl by lifting the pelvis rather than just moving the knees. Keep the breathing steady, use the floor to stay organized, and stop each set before momentum replaces abdominal tension.

Instructions

• Lie on your back on the floor with your arms down by your sides, palms pressing lightly into the ground for support.
• Bend your hips and knees so your thighs are up and your knees are roughly over your hips, with the shins close to parallel to the floor.
• Keep your low back gently connected to the floor and draw your ribs down before the first rep.
• Exhale and tuck your pelvis, then curl your tailbone off the floor to start lifting the hips.
• Bring the knees slightly toward your chest as the pelvis rolls upward; do not swing the legs.
• Lift only as high as you can while keeping the movement smooth and the neck relaxed.
• Pause briefly at the top, then lower the hips under control until the lower back returns to the floor.
• Reset the pelvis before the next rep and repeat for the planned number of repetitions.

Tips & Tricks

• Think about curling the pelvis upward, not throwing the feet overhead.
• Keep the knees bent throughout so the abs, not the hip flexors, drive the finish.
• If your lower back arches as you lower, shorten the range until you can keep it flat.
• A slow lowering phase usually exposes weak control better than adding more reps.
• Press your hands into the floor only enough to stay stable; do not turn it into an arm-driven press.
• Keep the chin gently tucked so the neck does not help lift the chest.
• Exhale as the hips curl up and inhale as you lower back down.
• Stop the set when the motion turns into leg swing or the pelvis stops rolling cleanly.

Frequently Asked Questions

What muscle does the Reverse Crunch target most?

It primarily targets the rectus abdominis, with the obliques and deep core muscles helping stabilize the torso.

How is this different from a regular crunch?

A regular crunch lifts the shoulders and upper spine, while a reverse crunch curls the pelvis upward and keeps the torso mostly fixed.

Do my feet have to touch the floor between reps?

No. Lower until the low back reconnects to the floor, then reset the pelvis and start the next rep without bouncing.

Why do my hip flexors take over this exercise?

If the knees straighten or the legs swing, the hip flexors start doing more of the work. Keep the knees bent and focus on rolling the pelvis.

Is the head supposed to come off the floor?

No. Keep the head and shoulders relaxed on the floor so the abs drive the movement instead of the neck.

Can beginners do Reverse Crunches?

Yes. Beginners usually do best with a small range of motion, bent knees, and a slow tempo until they can control the pelvic curl.

What should I do if I feel my lower back arching?

Shorten the lowering range and keep the ribs down so the pelvis stays tucked instead of tipping forward.

How should I breathe during each rep?

Exhale as you curl the pelvis up, then inhale as you lower under control.