core

Reverse Crunch

A lower-ab focused core exercise that curls the hips and knees toward the chest instead of lifting the shoulders like a standard crunch.

Equipment: bodyweight

How to do it

1Lie on your back with your knees bent and lifted so your shins are roughly parallel to the floor.
2Using your lower abs, curl your hips up off the floor, bringing your knees toward your chest.
3Squeeze briefly at the top of the motion.
4Lower back down under control without letting your feet touch the floor between reps.

Common mistakes

Using momentum to swing the legs instead of a controlled curl driven by the abs.
Letting the lower back arch off the floor during the lowering phase.

Sets & reps by goal

Goal	Sets	Reps	Rest
Strength	2-3	8-12	60-90 sec
Build muscle	2-3	10-15	45-60 sec
General fitness	2-3	12-15	45-60 sec

Ranges reflect the same goal-based logic used by the workout plan tool. Actual set count in a generated plan also depends on how often this muscle group appears elsewhere in your week.

Frequently asked questions

Is the Reverse Crunch safe for beginners?

Yes. The Reverse Crunch is tagged as beginner-friendly in GetFitArchitect's exercise database, meaning it doesn't demand much prior strength or mobility. Start with a weight or resistance level where you can complete every rep with good form, and only add load once that feels controlled.

What muscles does the Reverse Crunch work?

The primary mover is your core. As a core movement, it also involves your hip flexors and lower-back stabilizers.

How do I make the Reverse Crunch harder as I get stronger?

Since this is a bodyweight movement, progress by adding reps or sets before anything else, slowing the tempo down (especially the lowering portion), or shortening rest between sets. Once bodyweight reps stop feeling challenging, that's usually the sign to add external load or move to a more advanced variation.

Related exercises

Learn more

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