Reverse Crunch

CoreBW

A crunch variant where the hips and knees curl up toward the chest instead of the torso curling up toward the knees, emphasizing the lower rectus abdominis through posterior pelvic tilt.

Demo: General S&C demo

Sets

3

Reps

12-15

Rest

45s

Contraindications

Flexion-intolerant low back pain — reduce range of motion.

Setup

Lie on your back, knees bent to 90 degrees, hands at the sides or lightly under the low back.

Execution

  1. 1Brace the core and posteriorly tilt the pelvis, curling the hips off the floor
  2. 2Bring the knees up and slightly toward the chest
  3. 3Avoid using the legs to swing — the motion should come from the pelvis curling
  4. 4Pause briefly at the top
  5. 5Lower the hips back down with control, resisting a fast drop

Key cues

  • Curl the pelvis, don't just swing the knees
  • Keep the motion slow and controlled
  • Exhale on the curl up
  • Lower with control, don't let gravity do the work

Common faults

  • Swinging the legs with momentum instead of curling the pelvis
  • Using the hip flexors exclusively without any posterior pelvic tilt
  • Rushing the eccentric lowering
  • Arching the low back at the bottom instead of maintaining control

Tweaks

  • Straighten the legs for more difficulty
  • Add a stability ball squeeze between the knees
  • Slow the tempo for more time under tension

Progressions

Hanging Knee Raise

Muscles

Primary: Rectus Abdominis, Hip Flexors

Secondary: Obliques

Notes

FLEXION.

Sources

Attribution: Classic S&C canon