An apparatus for assisting and improving baseball hitting is described. The apparatus includes a spherical object having an interior anchor and a cord extending therefrom. An adjustable mass body is disposed within the spherical object along the cord. The interior anchor allows the spherical object to rotate about the cord.

An American style football including an inflatable bladder, a cover surrounding the bladder, a battery carried by the football, and a light emitter. The light emitter is carried by the football and is electrically connected to the battery. At least a portion of the cover transmits light from the light emitter.

An American style football including an inflatable bladder, a cover surrounding the bladder, a battery carried by the football, and a light emitter. The light emitter is carried by the football and is electrically connected to the battery. At least a portion of the cover transmits light from the light emitter.

An inflatable sports ball is provided. The inflatable sports ball having a bladder defining an exterior bladder surface and a bladder circumference. The inflatable sports ball may further comprise a cover disposed about the bladder, the cover comprising an outer cover layer and an intermediate structure. The intermediate structure is disposed between the outer cover layer and the bladder. The intermediate structure comprises a restriction structure. The restriction structure may comprise a plurality of overlapping strips. Each of the overlapping strips is interwoven with each of the other strips and wrapped about the bladder circumference. In this way, the restriction structure comprises a uniform number of radially-stacked layers of the overlapping strips over a substantial entirety of the exterior bladder surface between the exterior bladder surface and the outer cover layer.

A sports ball system for calculating movement characteristics has a sports ball. The sports ball monitors movement characteristics of the sports ball. A plurality of wearable devices is worn by a batter whom the sports ball is being thrown towards. At least one of the plurality of wearable devices receiving and displaying data transmitted by the sports ball and a remaining plurality of wearable devices recording data relating to movement of the batter.

A rotating spin top device for creating rotational force for a spin top includes a shell. The shell has a radius being a length between a center of the shell and an exterior surface of the shell. The shell has a cavity where a ball is nested within. The ball has a radius being a length between a center of the ball and an exterior surface of the ball. A length from the center of the ball to a center of the cavity defines a distance when the ball is positioned at an end of a pair of ends of the cavity. The radius of the ball and the radius of the shell are relative to the distance whereby defining a proportion. The proportion creates the rotational movement of the rotating spin top device.

A golf ball according to the present invention includes: a module including an electronic circuit and its power source; a protective layer that surrounds an outer periphery of the module and is formed from a material having a Shore D hardness of at least 60; a core that surrounds an outer periphery of the protective layer; and a cover that surrounds an outer periphery of the core. A weight may be arranged on a surface of the protective layer. A difference between a value MOImax of the moment of inertia in a direction in which the moment of inertia of the golf ball is maximum and a value MOImin of the moment of inertia in a direction in which the moment of inertia of the golf ball is minimum is at most 1.0 g.Math.cm.sup.2.

A rotating spin top device for creating rotational force for a spin top includes a shell. The shell has a radius being a length between a center of the shell and an exterior surface of the shell. The shell has a cavity where a ball is nested within. The ball has a radius being a length between a center of the ball and an exterior surface of the ball. A length from the center of the ball to a center of the cavity defines a distance when the ball is positioned at an end of a pair of ends of the cavity. The radius of the ball and the radius of the shell are relative to the distance whereby defining a proportion. The proportion creates the rotational movement of the rotating spin top device.

A rotating spin top device for creating rotational force for a spin top includes a shell. The shell has a radius being a length between a center of the shell and an exterior surface of the shell. The shell has a cavity where a ball is nested within. The ball has a radius being a length between a center of the ball and an exterior surface of the ball. A length from the center of the ball to a center of the cavity defines a distance when the ball is positioned at an end of a pair of ends of the cavity. The radius of the ball and the radius of the shell are relative to the distance whereby defining a proportion. The proportion creates the rotational movement of the rotating spin top device.

A hollow, compressible or rigid hollow body has mechanical retaining devices such as sound generators, scent capsules, LED lights and vibrating mechanisms and identifying or responding detection elements held, secured and locked therein without the use of any solvents, glues, sonic welding, spin welding or other bonding materials. The hollow contaminant-free bodies are particularly useful for animals and recreation. Some of the above contain carcinogens harmful to animals if ingested.