1, thoracic vertebra correction. Sit in a chair, put your hands around the cervical vertebra, don't look up too much, stick the upper thoracic vertebra on the back of the chair, stretch the thoracic vertebra backwards, and feel the feeling of pushing the thoracic vertebra forward. Hold 10 second, repeat four groups, and be careful not to push too hard. 2. Strengthen upper back muscles. This action is called bending over the bird, and many fitness students should be familiar with it. Lift two hand-held dumbbells to both sides until the upper arm is parallel to the back, pause, and then put down the dumbbells to recover. Don't shrug your shoulders when you do it, each group 15 times, and repeat 4 groups.