Sit upright on a raised surface or chair so that your hips are higher than your knees and your feet are hip width apart.
Sit close to the edge so that you are taking your weight through your legs.
Ask an assistant to hold one end of an exercise band and stand to your side.
Hold the other end of the exercise band in both hands with your arms outstretched in front of you.
Ask the assistant to gently increase the tension in the band as you attempt to stay still through your arms and body.
Ask the assistant to vary the direction of pull on the band, from right to left, and diagonally up and down.