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  7. 90 Degree Heel Touch

Exercise guide

90 Degree Heel Touch

  • Beginner
  • Compound
  • Rep-based
  • Waist

The 90 Degree Heel Touch is a core isolation exercise that targets the obliques and rectus abdominis through lateral flexion. It is highly effective for improving waistline definition and developing lateral core stability without the need for equipment.

Reviewed by the Crucible team · Updated June 2026

Watch the 90 Degree Heel Touch 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 with your knees bent at 90 degrees and feet flat on the floor, hip-width apart.
  2. Extend your arms straight by your sides with palms facing inward.
  3. Lift your head, neck, and shoulder blades slightly off the mat to create initial tension in your upper abdominals.

How to do it

  1. Exhale and crunch your torso laterally to the right, reaching your right hand to touch your right heel.
  2. Inhale as you return to the center starting position while keeping your shoulders elevated.
  3. Exhale and repeat the movement to the left side, reaching for your left heel.
  4. Continue alternating sides in a smooth, controlled rhythm.

Form checklist

  • Keep your lower back pressed firmly into the floor at all times.
  • Maintain a consistent gap between your chin and chest to avoid neck strain.
  • Focus on moving your ribcage toward your hip rather than just swinging your arms.
  • Keep your shoulder blades off the ground throughout the entire set.

Pro tips

  • Visualize 'closing the gap' between your lower ribs and your hip bone to maximize oblique contraction.
  • Hold the peak contraction for one second at the heel touch to increase time under tension.

Make it harder

  • Walk your feet further away from your glutes to increase the distance you must crunch to reach your heels.
  • Slow down the tempo significantly, taking 3 seconds to reach the heel and 3 seconds to return to center.

Frequently asked

What muscles does the 90 degree heel touch work?
The 90 degree heel touch primarily targets the abs and obliques, and also works the erector spinae as secondary muscles.
What equipment do you need for the 90 degree heel touch?
The 90 degree heel touch requires no equipment — just your body weight.
Is the 90 degree heel touch good for beginners?
Yes. The 90 degree heel touch 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 90 degree heel touch into a precise program around your body, equipment, location, and time.

Download on the App Store