- Arm I (lifestyle intervention): Patients undergo moderate-intensity aerobic-exercise sessions 3 to 5 days a week for 24 weeks. Patients not able to attend five supervised sessions are counseled on how they can fit an extra 1-2 home/community-based exercise sessions into their weekly routine. All sessions of physical activity are recorded in a physical activity log. Portable pedometers are used to determine the number of steps/distance walked each day. Patients wear heart-rate monitors throughout the exercise sessions. Heart rate and ratings of perceived exertion are assessed at regular intervals. The exercise-therapy sessions use a variety of cognitive-behavioral techniques for promoting exercise adherence as well as positive attitudes and experiences.