In order to stabilize the arm as you speed up your rotation, we have developed the following exercise. After you use it to develop a sense of how your body is moving, you will likely forget it. If at some future time you find your shots becoming inconsistent, you might come back to this exercise.

The exercise is illustrated in the figure above. In this figure, Becky is positioning her index finger and thumb between her elbow and hip with a space of 4 to 6 inches. Then, as she rotates, she maintains this distance. This exercise starts the process of creating an awareness (in technical terms, somatosensory mesoscopic assemblies) of the relative position of your elbow and hip.

Why Bother?

In order for you to become consistent at high ball speeds, you need to develop an advanced sense of your body movements. It sounds like a big effort, but it is not. You might develop this sense in a few minutes. Neural plasticity allows even very complex motions to be achieved due in as little as forty minutes. For high-speed tennis, you must rotate quickly while maintaining control of your arm position. If you have no internal awareness of this position, you will find that your elbow can drift outward, causing the racquet to turn downward.

The point of an exercise is not to form a rule or habit, but rather to develop a sense of your body's movement for use as the situation requires. When you are playing, your brain will make use without your awareness of the connections you develop from an exercise. You will experience this in the form of increased consistency.