Tennis racquets with old type of strings did not allow power and control over the racquet at the same time. To get a powerful stroke player had to hit the ball with the area of racquet closer to the tip of the racquet (toe). To obtain control and to reduce vibration of the racquet, player had to hit the ball with the area of racquet called “sweet spot”, located around the geometric center of the head. NASA’s 1973 Skylab 3 mission showed that tapered strings can move the “sweet spot” from the center of the racquet toward the position of greater power.