How to perform the exercise
Lie on your back on a mat with your legs extended in front of you and backs of heels on the floor.
Grab hold of your right knee and gently pull it up to your chest until you can feel a slight stretch in your lower back.
Try to bring the knee as close to your chest as is comfortable while keeping the left leg relaxed.
Hold the stretch and then release the leg to starting position.
Repeat with the left leg.