Criss Cross Knee Tuck

Muscles worked

Setup

1. Sit on the floor with your knees bent and feet flat.
2. Lean your torso back at a 45-degree angle, supporting yourself with your hands placed slightly behind your hips, fingers pointing forward.
3. Lift your feet off the floor, bringing your knees toward your chest to find your balance point on your sit bones.

How to do it

1. Inhale and extend your legs straight out in front of you at a 45-degree angle while leaning your torso back slightly further.
2. Exhale and pull your knees back toward your chest while rotating your torso to drive your right knee toward your left shoulder.
3. Inhale as you extend back to the center 'V' position with legs straight.
4. Exhale and repeat the tuck, this time rotating your torso to drive your left knee toward your right shoulder.

Form checklist

• Keep your chest lifted and avoid rounding your shoulders or collapsing your spine.
• Maintain a slight 'hollow body' tension in the abs to protect the lower back.
• Ensure the rotation originates from the waist and ribcage rather than just swinging the legs.
• Keep your feet hovering off the floor throughout the entire set.

Pro tips

• Focus on the mind-muscle connection by visualizing your ribcage moving toward the opposite hip bone during the twist.
• Pause for a split second at the peak of the tuck to maximize the peak contraction in the obliques.

Make it harder

• Remove your hand support and hold your arms out to the sides or behind your head to significantly increase the balance challenge.
• Slow the tempo to a 3-second extension phase to increase time under tension for the lower abdominals.

Frequently asked

What muscles does the criss cross knee tuck work?

The criss cross knee tuck primarily targets the abs and obliques, and also works the erector spinae as secondary muscles.

What equipment do you need for the criss cross knee tuck?

The criss cross knee tuck requires no equipment — just your body weight.

Is the criss cross knee tuck good for beginners?

The criss cross knee tuck 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 Degrees Arms PlankIntermediate · abs, deltoids, obliques, and pectorals