You will need an assistant for this exercise.
Lie on your back with a buoyancy collar around your neck and a noodle under your hips.
Place an inflatable ring on your affected leg.
Hold onto the pool side with your nearest hand, you will be exercising your opposite leg.
Ask your assistant to stand beside your affected leg.
Try to take your leg out to your side as your assistant generates turbulence to assist this movement.
Return to the start position and repeat.