Thoracic Flexibility

You potentially get 30° more rotation around the axis of the spine in the thoracic — where the ribs are — than in the lumbar. The lumbar is mostly for support; the thoracic is for rotation. You are moving left and right, so don't forget to double that number: 30° rotation in the lumbar total and more than 90° in the thoracic. Part of the secret is movement in the costovertebral joints between the rib-heads and the spine. If the ribs can move — and they can — then the thoracic spine is where you want more of your rotation. And since almost everyone over-uses their lumbar and under-utilizes their thoracic rotation, freeing the ribs so that you can get more of your rotation from your thoracic spine: that is so good for you.