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  7. Reverse Crunch

Exercise guide

Reverse Crunch

  • Beginner
  • Compound
  • Rep-based
  • Waist

The reverse crunch is a highly effective core exercise that targets the lower rectus abdominis and obliques by utilizing a posterior pelvic tilt. It strengthens the deep core and improves pelvic stability while minimizing neck strain compared to traditional crunches.

Reviewed by the Crucible team · Updated June 2026

Watch the Reverse Crunch demonstrationGuided video and your full workout live in the Crucible app.

Muscles worked

Primary

  • Abs
  • Obliques

Secondary

  • Erector spinae

Equipment

  • Body weight

Setup

  1. Lie flat on your back on a mat with your arms by your sides and palms facing down for stability.
  2. Bend your knees at a 90-degree angle and lift your feet off the floor so your thighs are perpendicular to the ground.
  3. Press your lower back firmly into the mat to engage your core and eliminate any arch in your spine.

How to do it

  1. Exhale and contract your lower abdominals to curl your hips off the floor, bringing your knees toward your chest.
  2. Focus on 'rolling' your pelvis toward your ribcage rather than just swinging your legs upward.
  3. Inhale as you slowly lower your hips back to the starting position using a controlled 2-second tempo.
  4. Stop the descent just before your lower back begins to arch or your feet touch the floor to maintain constant tension.

Form checklist

  • Keep your head, neck, and shoulders relaxed on the floor throughout the entire set.
  • Avoid using momentum or 'kicking' your legs to lift your hips off the mat.
  • Ensure the movement comes from the contraction of the abs, not from pushing down with your arms.
  • Maintain the 90-degree bend in your knees to keep the focus on the core rather than the hip flexors.

Pro tips

  • Visualize trying to touch your hip bones to your bottom ribs to maximize the shortening of the abdominal wall.
  • Pause for a split second at the top of the movement to emphasize the peak contraction of the lower abs.

Make it harder

  • Straighten your legs completely to increase the lever length and the resistance placed on the abdominal muscles.
  • Perform the exercise on a decline bench to increase the range of motion and work against a steeper angle of gravity.

Frequently asked

What muscles does the reverse crunch work?
The reverse crunch primarily targets the abs and obliques, and also works the erector spinae as secondary muscles.
What equipment do you need for the reverse crunch?
The reverse crunch requires no equipment — just your body weight.
Is the reverse crunch good for beginners?
Yes. The reverse crunch is a beginner-friendly movement and a strong foundation to build on.

Related exercises

  • 3/4 Sit-UpBeginner · abs and obliques
  • 45 Degree Bicycle Twisting CrunchIntermediate · abs and obliques
  • 45 Degree Lean Back Alternate Knee RaiseBeginner · abs and obliques
  • 45 Degrees Arms PlankIntermediate · abs, deltoids, obliques, and pectorals

Train this with a plan, not guesswork

Crucible builds the reverse crunch into a precise program around your body, equipment, location, and time.

Download on the App Store