While tennis racquets can be picked off the shelf in any sports equipment shop, professionals prefer to have their racquets customized during the manufacturing process itself, taking into account extra graphite reinforcement, weight, balance, handle shape, etc. This is often called ?tweaking? the racquets to help improve the play.
Even if a racquet appears to be a simple piece of sports equipment, there are many factors that go into the making of it. The tension in a racquet?s strings is an important element because any ?creep? in the strings can affect performance. Of equal significance is the balance of the racquet, which is the weight distribution that is measured from the butt end in inches or centimeters.
Generally, racquets are made ?head light? to allow for better maneuverability. However, today?s super light racquets are made ?head heavy? to supply enough mass to the area of the frame where the ball is being contacted in order to add power to the racquet.
Damping refers to vibration and the handles are devised to reduce frame shock when the ball hits it at full force. Elasticity is the string?s stretch quotient, which is measured in terms of the strings? ability to return to its original position after contact with the ball. Professionals are also very particular about ?pick up? weight, which is a measure of how a racquet feels when picked up from the handle end.
The performance of a racquet also dependents on what is known as the ?sweet spot? or the center of percussion. It is dependent on the location of the axis of rotation of the hand in the stroke. The “sweet” area on the string bed is where the racquet’s bounce is maximized. Those who have been playing tennis for a long time know the value of ?moment,? the turning force pivoting the racquet head down when it is held parallel to the ground. What counts is moment and not weight, but amateur tennis players are often misled into buying racquets that seem light in weight because they have picked them up from the wrong end.
Torque is an equally important contributing factor that is measured as the bending force resulting from impact that causes the hand to bend back and then catapult forward. Professional players tend to prefer the slim, more flexible racquets that absorb torque in frame bending, thereby reducing the catapulting force that flings the racquet forward after impact.
Along the same lines, factors like impulse reaction (the push and pull on the axis of rotation), shock (a sudden change in the racquet’s kinetic energy on impact) and shoulder pull (the force exerted by the shoulder muscles in opposing the centrifugal force acting on the racquet), all contribute to the overall quality of a racquet.