The lying twist helps with mobility of your trunk and your hips.
Lie on your back with both legs bent and your feet flat on the floor and your arms spread out to the sides.
Keeping your legs together, drop your knees down to one side whilst simultaneously turning your head away in the opposite direction.
Hold this position, before you bring your legs and head back to the starting position and repeat on the other side.
Increase the depth to which you lower your knees.