Forehands and backhands are the most basic and most important of tennis skills. The stability of positive and negative strikes is necessary for athletes of all levels. Wrong use of wrist movements can easily damage the stability of the fore and back hands. People's wrists are very flexible, because of its flexibility, they naturally think it is easy to control. In fact, if you want to hit the ball with a weak wrist, not only will the result be bad, but it will also be easy to get injured.