Core · Abs
Reverse crunch
How to do the reverse crunch: curling the pelvis without momentum, common mistakes, progressions and why it is a good option if your neck bothers you.
| Focus | Abs · obliques |
| Movement | Leg raise |
| Equipment | Bodyweight |
| Suggested sets | 3 × 15 |
| Estimated time | ≈ 4 min |
| Joints loaded |
Technique video
The reverse crunch is the crunch "in reverse": instead of lifting your torso, you lie on your back, bring your knees toward your chest and lift your pelvis off the floor. It is often associated with the lower abs and has a practical advantage: it does not strain the neck, because your head stays on the floor.
Muscles worked
The rectus abdominis, which curls the pelvis toward the ribs. The obliques assist. The hip flexors help bring the legs in, but the goal is for the abs to do the final work of lifting the pelvis.
How to do it
- Lie on your back with your hands by your sides or holding a bench behind your head.
- Lift your legs with your knees bent at 90°, feet off the floor.
- Breathing out, curl your pelvis by bringing your knees toward your chest and lifting your butt a few centimeters off the floor.
- Hold for a second at the top.
- Lower your pelvis slowly without dropping your legs.
Common mistakes
- Swinging your legs for momentum.
- Only moving your legs without lifting the pelvis: the hip flexors work, not the abs.
- Dropping back down.
- Fully straightening your legs, which arches the lower back.
Progressions
- Easier: smaller range, with your feet close to the floor.
- Harder: on a decline bench, or the captain's chair leg raise.
Do 12–20 slow reps.
Precautions
It does not load any joint significantly. Since your feet are off the floor, it suits an ankle injury, and since your head stays down, it suits neck pain.
Log your sets for this exercise and see your progress month by month.
Start for freeIf you have an injury, pain or a medical condition, check with a professional before doing this exercise.