The Twist: Nearly every major muscle group—from your shoulders to your legs—has to work against the resistance of the band. Sit with right leg extended and wrap the center of band around your left foot, left knee bent and foot flexed. Hold both ends of band in your left hand in front of your chest, elbow pointing out to the side and palm facing the ground (choke up on band so it's taut). Lean back as you extend left leg out 45 degrees and rotate shoulders to the left. Return to starting position. Switch sides to complete set.