Dorsal dispute . Exercise 2 - Spine Twist  Stand with your feet wide apart , sit down backwards with the knees and feet outward . Sit down backwards and place your hands on your knees. Rotate your upper body and one shoulder toward the other side's knee . Be sure to keep your back perfectly straight throughout the exercise , let it rotate like a spiral . Reinforce the stretch by pushing away from his hand gently and feel like you can rotate a bit , make sure the spine is completely straight .