Lie on your back with your legs hips width apart.
Bend the leg you want to strengthen, keeping your foot on the floor.
Your knee and foot should still be in alignment with your hip.
Tighten your abdominal and buttock muscles and lift your hips up off the floor, allowing your straight leg to lift with the movement.
Your thighs should remain level.
Ensure your hips do not drop on the side of your straight leg.
Control the movement as you lower your hips back down to the floor and repeat the movement.