Standing with the band attached at chest height or higher, hold each end of the band with your hands and bring your arms up in front of your body to shoulder height. From this position, keep your shoulder blades down and back and bring your hands down toward your pockets, making sure that your elbows stay extended as shown.
Standing with your feet shoulder width apart and your knees slightly bent, hold onto the band and rotate your trunk pulling the band from high to low as shown. Attaching the band to the top of a door may be an easy way to secure the band. You should not feel an increase in back pain during this exercise.