Both groups will wear a pedometer attached to a gait belt worn around their waist in order to record the number of steps taken in a 24-hour period of time. A pedometer will also be attached to each rocking chair in order to record the number of rocks in a 24-hour period. Participants in each group will be encouraged by the research staff to increase the time spent rocking, sitting in the non-rocking chair, and walking each day. You will be given pain medication as needed.