Diagonal In Out On Chair

Muscles worked

Setup

1. Sit on the front edge of a sturdy, non-rolling chair with your feet flat on the floor.
2. Lean your torso back at a 45-degree angle while keeping your spine neutral and chest lifted.
3. Grip the sides or front of the chair seat firmly for stability and lift your feet 2-3 inches off the floor.

How to do it

1. Exhale as you pull your right knee diagonally toward your left shoulder, rotating your torso slightly toward the rising knee.
2. Inhale as you extend your leg back to the starting position with control, keeping the foot hovering off the ground.
3. Alternate sides by pulling your left knee toward your right shoulder on the next breath.
4. Maintain a steady, rhythmic tempo, focusing on the contraction of the abdominal wall.

Form checklist

• Keep your lower back flat or slightly arched; do not allow your spine to round forward.
• Ensure the movement comes from your core, not by pulling with your hip flexors alone.
• Keep your shoulders down and away from your ears to avoid neck tension.
• Maintain a constant hover with your feet to keep the abs under continuous tension.

Pro tips

• Think about bringing your opposite ribcage toward your hip to maximize oblique engagement.
• Pause for a split second at the peak of the tuck to emphasize the mind-muscle connection with your lower abs.

Make it harder

• Perform the movement with your hands behind your head (prisoner style) to remove the stability of the chair grip.
• Slow down the extension phase to a 3-second count to increase time under tension.

Frequently asked

What muscles does the diagonal in out on chair work?

The diagonal in out on chair primarily targets the abs and obliques, and also works the erector spinae as secondary muscles.

What equipment do you need for the diagonal in out on chair?

The diagonal in out on chair requires no equipment — just your body weight.

Is the diagonal in out on chair good for beginners?

Yes. The diagonal in out on chair is a beginner-friendly movement and a strong foundation to build on.

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• 45 Degrees Arms PlankIntermediate · abs, deltoids, obliques, and pectorals