In the majority of the tennis strokes, you have to perform an upper body rotation, rotating and loading in your hips. But a lot of trunk rotation also comes from the thoratic (upper back) spine. Overuse and small micro tears cause the upper back muscles to tighten to protect themselves. If the upper back becomes weak and tight you can experience severe problems and pains. The tight muscles don’t allow as much blood into them, so there is not enough supply of nutrients and energy needed to stay healthy. Tight muscles eventually get weak and then tighten even more. That is a vicious circle that you need to break. If you don’t stretch properly, especially after your training or practice, the muscle never gets elongated to its natural length and over time will adapt and become short.
