Lying Supine Straight Knee Raise

Muscles worked

Setup

1. Lie flat on your back on a mat with both legs extended straight and feet together.
2. Place your hands flat by your sides or tucked slightly under your glutes for additional lower back support.
3. Engage your core by pressing your lower back firmly into the floor to eliminate any arching.
4. Keep one leg resting on the floor while the working leg is prepared for the lift.

How to do it

1. Exhale as you lift the working leg toward the ceiling, keeping the knee locked perfectly straight.
2. Continue the lift until the leg is at a 45 to 90-degree angle, or as high as you can go without your lower back lifting off the floor.
3. Inhale as you lower the leg back toward the floor using a slow, controlled 2-3 second tempo.
4. Stop the descent just before your heel touches the ground to maintain constant tension, then repeat for the desired reps before switching sides.

Form checklist

• Keep the lower back glued to the floor throughout the entire movement.
• Ensure the knee of the working leg remains fully locked and does not bend.
• Maintain a neutral neck by looking straight up at the ceiling.
• Avoid using momentum or swinging the leg; focus on a smooth, rhythmic motion.

Pro tips

• Squeeze your quadriceps as hard as possible to ensure the leg stays straight, which increases the leverage and difficulty for the lower abs.
• Focus on the 'mind-muscle connection' by imagining your lower abdominals pulling the weight of your leg upward.

Make it harder

• Hover the non-working leg two inches off the floor while the working leg performs the repetitions.
• Add a 2-second pause at the top of the movement to maximize the peak contraction of the hip flexors and core.

Frequently asked

What muscles does the lying supine straight knee raise work?

The lying supine straight knee raise primarily targets the abs, and also works the hip flexors as secondary muscles.

What equipment do you need for the lying supine straight knee raise?

The lying supine straight knee raise requires no equipment — just your body weight.

Is the lying supine straight knee raise good for beginners?

Yes. The lying supine straight knee raise is a beginner-friendly movement and a strong foundation to build on.

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