Seated Diagonal Crunch On Chair

Muscles worked

Setup

1. Sit on the front edge of a sturdy, armless chair with your feet flat on the floor, hip-width apart.
2. Maintain an upright posture with a tall spine and your shoulders pulled back.
3. Place your fingertips lightly behind your ears or at your temples, keeping your elbows flared out to the sides.

How to do it

1. Exhale as you lift your right knee toward your chest while simultaneously rotating your torso to bring your left elbow toward the rising knee.
2. Squeeze your obliques at the peak of the contraction, aiming to bring the shoulder across the body rather than just the elbow.
3. Inhale as you slowly lower your foot and return your torso to the upright, neutral starting position.
4. Repeat the movement on the opposite side, alternating in a controlled, rhythmic tempo.

Form checklist

• Avoid pulling on your neck with your hands; let the core do the work.
• Keep your chest open and avoid rounding your upper back excessively.
• Ensure your stationary foot remains firmly planted for stability.
• Focus on rotating the ribcage toward the opposite hip.

Pro tips

• To maximize oblique recruitment, think about 'shortening' the distance between your bottom rib and the opposite hip bone.
• Pause for one second at the point of maximum contraction to increase time under tension.

Make it harder

• Perform the movement with both feet hovering an inch off the floor throughout the entire set.
• Hold a light medicine ball or weighted object against your chest to increase the resistance during the rotation.

Frequently asked

What muscles does the seated diagonal crunch on chair work?

The seated diagonal 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 diagonal crunch on chair?

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

Is the seated diagonal crunch on chair good for beginners?

The seated diagonal crunch on chair is rated intermediate. Build a base with simpler variations first, then progress to it with light load and strict form.

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• 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