Lying Side Straight Legs Reverse Crunch

Muscles worked

Setup

1. Lie on your side with your legs stacked and fully extended, creating a straight line from head to heels.
2. Place your bottom arm out at a 45-degree angle for balance and your top hand behind your head or on the floor for support.
3. Engage your core and squeeze your thighs together to lock your legs in place.

How to do it

1. Exhale and lift both legs toward the ceiling while simultaneously crunching your upper torso sideways toward your hips.
2. Focus on 'closing the gap' between your ribs and hip bone using your obliques to drive the lift.
3. Inhale and slowly lower your legs and torso back toward the floor with a controlled 2-second eccentric phase.
4. Stop just before your feet touch the ground to maintain constant tension before starting the next rep.

Form checklist

• Keep your knees locked and quads tight to maintain perfectly straight legs throughout.
• Avoid rolling onto your glutes; stay stacked on your side hip to isolate the obliques.
• Keep your neck in line with your spine rather than pulling your chin to your chest.
• Ensure the movement is driven by the core, not by pushing off the floor with your bottom arm.

Pro tips

• Imagine trying to touch your top elbow to your top hip to maximize the lateral contraction at the peak of the movement.
• Squeeze your inner thighs together throughout the set to stabilize the pelvis and increase lower-ab engagement.

Make it harder

• Increase the time under tension by adding a 3-second isometric hold at the peak of the contraction.
• Perform the movement with a small medicine ball or light dumbbell held between your ankles.

Frequently asked

What muscles does the lying side straight legs reverse crunch work?

The lying side straight legs reverse crunch primarily targets the abs and obliques, and also works the hip flexors as secondary muscles.

What equipment do you need for the lying side straight legs reverse crunch?

The lying side straight legs reverse crunch requires no equipment — just your body weight.

Is the lying side straight legs reverse crunch good for beginners?

The lying side straight legs reverse crunch is rated intermediate. Build a base with simpler variations first, then progress to it with light load and strict form.

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