Abstract: A combination of an implement employed in a sports game to impact with a body, and a device coupled to the implement which measures the natural frequency and the relative amplitude of vibration of the implement resulting from the impact. The implement can be a game racket, bat, club or the like and the body impacted can be a ball. The lower the value of the natural frequency of vibration of the implement the more flexible the implement is when it impacts the ball, the greater is the amplitude of the vibration of the implement and the rebound of the ball has a lower velocity. One of the embodiments, called a FLEX METER is a frequency measuring device which employs a series of reeds mounted on a base member each reed being adjusted to vibrate at a maximum amplitude when a vibration having a designated frequency is applied to the base member. Each reed is identified with a designated frequency.

Abstract: A tennis racket having an unconventional weight and stiffness distribution providing for the same swing weight as rackets of the prior art, a large distance of the center of percussion from the handle end, and a weight means in the grip portion of the racket for reducing the shock and vibration transmitted to the player's arm, when the player impacts the ball with the racket.

Abstract: A tennis racket is provided having the same swing weight as rackets of the prior art, but having a significant reduction in the weight, and a significant increase in the distance of the center of percussion and in the distance of the center of gravity from the end of the handle. A significant reduction in the deflection and vibration of the racket caused by the impact of the ball is provided. The tendency of the racket to turn in the players hand when a ball hits the racket off of the longitudinal axis of the racket, is reduced.These improvements are accomplished by controlling the distribution of material and the crossectional shape along the length, width, and depth of the racket, and by the utilization of materials having a high stiffness and strength per unit weight.Methods are provided to measure the swing weight of the racket about selected axes and to measure the flexibility and vibratory characteristics of the racket.

Abstract: A tennis racket is provided having the same swing weight as rackets of the prior art, but having a significant reduction in the weight, and a significant increase in the distance of the center of percussion and in the distance of the center of gravity from the end of the handle. A significant reduction in the deflection and vibration of the racket caused by the impact of the ball is provided. The tendency of the racket to turn in the players hand when a ball hits the racket off of the longitudinal axis of the racket, is reduced.These improvements are accomplished by controlling the distribution of material and the cross-sectional shape along the length, width, and depth of the racket, and by the utilization of materials having a high stiffness and strength per unit weight.Methods are provided to measure the swing weight of the racket about selected axes and to measure the flexibility and vibratory characteristics of the racket.

Abstract: A tennis racket is provided having the same swing weight as rackets of the prior art, but having a significant reduction in the weight, and a significant increase in the distance of the center of percussion and in the distance of the center of gravity from the end of the handle. A significant reduction in the deflection and vibration of the racket caused by the impact of the ball is provided. The tendency of the racket to turn in the players hand when a ball hits the racket off of the longitudinal axis of the racket, is reduced.These improvements are accomplished by controlling the distribution of material and the cross-sectional shape along the length, width, and depth of the racket, and by the utilization of materials having a high stiffness and strength per unit weight.Methods are provided to measure the swing weight of the racket about selected axes and to measure the flexibility and vibratory characteristics of the racket.

Abstract: A tennis racket having an unconventional weight and stiffness distribution providing for the same swing weight as rackets of the prior art, a large distance of the center of percussion from the handle end, and a weight means in the grip portion of the racket for reducing the shock and vibration transmitted to the player's arm, when the player impacts the ball with the racket.