Seated Straight Leg Crunch On Chair

Muscles worked

Setup

1. Sit on the front edge of a sturdy, armless chair with your feet flat on the floor.
2. Grip the sides or front of the chair seat firmly with both hands for stability.
3. Extend your legs straight out in front of you with your heels lightly touching the floor.
4. Lean your torso back slightly (about 20-30 degrees), keeping your spine neutral and chest lifted.

How to do it

1. Exhale and contract your abdominals to lift both legs toward the ceiling while keeping them perfectly straight.
2. Simultaneously bring your chest slightly forward toward your knees to create a 'V' shape with your body.
3. Inhale and slowly lower your legs back to the starting position, stopping just before your heels touch the floor.
4. Maintain a controlled 2-1-2 tempo (2 seconds up, 1 second hold, 2 seconds down).

Form checklist

• Keep your legs straight and knees locked throughout the entire set.
• Avoid rounding your lower back; maintain a proud chest and neutral spine.
• Ensure the movement is driven by your core rather than swinging your legs with momentum.
• Keep your neck neutral by looking slightly forward rather than down at your lap.

Pro tips

• Focus on the 'hollow body' sensation by pulling your belly button toward the back of the chair during the lift.
• To increase oblique engagement, perform a slight torso twist toward the knees at the peak of the contraction.

Make it harder

• Hover your heels 2 inches off the floor between reps to maintain constant tension on the abs.
• Hold a light object, like a water bottle or small pillow, between your feet to add resistance.

Frequently asked

What muscles does the seated straight leg crunch on chair work?

The seated straight leg crunch on chair primarily targets the abs and obliques, and also works the erector spinae as secondary muscles.

What equipment do you need for the seated straight leg crunch on chair?

The seated straight leg crunch on chair requires no equipment — just your body weight.

Is the seated straight leg crunch on chair good for beginners?

Yes. The seated straight leg crunch on chair is a beginner-friendly movement and a strong foundation to build on.

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• 45 Degree Lean Back Alternate Knee RaiseBeginner · abs and obliques
• 45 Degrees Arms PlankIntermediate · abs, deltoids, obliques, and pectorals