A hollow golf club head having face end and tail ends, a strike face at the face end, a crown, a sole, and a structural response modifying constraining member having first and second ends, the second being forward of the first and spaced from the strike face, the constraining member extending vertically and in contact with the sole and the crown at its first and second ends, and extending horizontally distance that is substantially less than the sole length, when the club head is in address position.

A ball includes a first housing, at least a fixing body, at least a ceramic vibration unit and a second housing. The fixing body is disposed on the internal wall of the first housing. The ceramic vibration unit is configured to make a sound and is fixed on the fixing body. The ceramic vibration unit includes a vibrating plate, a ceramic sheet and a cover body. The ceramic sheet and the cover body are disposed on the vibrating plate, and the ceramic sheet is located between the vibrating plate and the cover body. The second housing covers the first housing.

A golf club includes a shaft, and a club head provided at an end of the shaft, wherein: the club head includes a head body and plate-like face member provided as a hitting face of the head body; and the face member is fixed to the head body only at a part of an upper or lower edge surface, or parts of both upper and lower edge surfaces of the face member. A fixing position of the face member may be located in the proximity of a node of a characteristic vibration in a case of freely supporting the face member. The Rockwell C-scale hardness of the face member is preferably no less than 40. The face member may be fixed to the head body by a set screw, at two locations of the upper edge surface, and two locations of the lower edge surface of the face member.

An apparatus for golf training includes a wrist strap and a ring which are shaped and sized to be worn by a user. A cable extends between the wrist strap and the ring, and certain movements thereof are configured to provide an indication of improper swing form using an audible stimulus

An exercise machine carriage handle system for providing handles for an exerciser to grasp with their hands thereby expanding the type of exercises that may be performed. The exercise machine carriage handle system generally includes a frame having a track, a carriage movably connected to the track, a bias member connected between the frame and the carriage, a first handle connected to the carriage near the first side, and a second handle connected to the carriage near the second side. The first handle and second handle are adapted for grasping with a first hand and a second hand respectively of a user during the performance of an exercise on the exercise machine.

A golf club head includes a body having a recessed channel formed in an outer surface. A weight assembly that includes a weight at least partially disposed within the recessed channel, a cover extending at least partially over the recessed channel, and a fastener coupling the cover to the body. The fastener is adapted to retain the weight in the recessed channel only indirectly by the cover. The weight is slidably engaged with the cover and the cover is positionable in at least an unlocked configuration whereby the cover is raised at least partially out of the recessed channel and the weight is selectively slidable within the recessed channel, and a locked configuration whereby the cover is at least partially disposed within the recessed channel and the weight is secured within the recessed channel. The weight moves with the cover between the unlocked configuration and the locked configuration.

A low friction rehabilitation board having an integral band retaining feature is described. The rehabilitation board may have a coefficient of static friction of no more than about 0.5 and in some embodiments no more than about 0.06. The rehabilitation board has a plurality of band retaining feature configured along one or both ends and may be an integral band retaining features being formed in the board. Additionally, the rehabilitation may include one or more band retaining features on one or both sides of the board. The unique configuration of the band retaining features enables rehabilitation method heretofore not possible with a single board. Resistance bands may be retained in the band retaining features and coupled to a user's limb, such as a foot or ankle, to resist motion, such as sliding or extending the foot along the low friction surface of the rehabilitation board.

A swing speed training club includes a shaft having a proximal end and a distal end; and a head portion affixed to the distal end of the shaft and having a body having a proximal end and a distal end. The head portion is configured to produce a distinctive sound when the head portion is swung through the air at the distal end of the club shaft at a suitable speed.

An apparatus, kit, and method for rehabilitating and/or strengthening the soft tissues of a user's lower arm is disclosed. The apparatus has a first arm with a proximal end and a distal end; a second arm with a proximal end, a distal end, one or more discrete sections therebetween for engaging one or more weights, and a means for providing an audible feedback to the user upon completion of an exercise repetition or a half-repetition; and a hinge in contact with the proximal ends of the first and second arms. The hinge is configured to adjust the distance between the distal ends of the first and second arms, or the angle separating the first and second arms.

Disclosed is system and method for measuring the tension of a tennis net, and, alternatively or in addition, for determining if a service let occurs via the measuring of the net tension. The disclosed embodiments measure a force exerted on the center-strap or the singles stick by the net. In these embodiments, the measured force provides an accurate reflection of the tension of the net.