Present invention discloses a golf swing practicing apparatus for practicing golf swing in a confined environment with a short-shaft golf club, practicing methods for setting up the short-shaft golf club at a proper incline angle in mid air at address position, and a mechanic model for determining the required club head weight that enables golfer to feel the same Swing Weight as he swings the short-shaft golf club or the conventional golf club.

A golf club 2 includes a head 4, a shaft 6, and a grip 8. A club inertia moment about a swing axis is defined as Isw. A club inertia moment about a grip end is defined as Ige. Ige is 2870 (kg.Math.cm.sup.2) or greater and less than 2920 (kg.Math.cm.sup.2). Isw/Ige is equal to or less than 2.46. A club weight is defined as Wc (kg), an axial direction distance from the grip end to a center of gravity of the club is defined as Lc (cm), and a club inertia moment about the center of gravity of the club is defined as Ic (kg.Math.cm.sup.2). Isw is calculated by Equation (1) below. Ige is calculated by Equation (2) below.
Isw=Wc×(Lc+60).sup.2+Ic  (1)
Ige=Wc×(Lc).sup.2+Ic  (2)

A golf club 2 includes a head 4, a shaft 6, and a grip 8. A club inertia moment about a swing axis is defined as Isw. A club inertia moment about a grip end is defined as Ige. Ige is 2870 (kg.Math.cm.sup.2) or greater and less than 2920 (kg.Math.cm.sup.2). Isw/Ige is equal to or less than 2.46. A club weight is defined as Wc (kg), an axial direction distance from the grip end to a center of gravity of the club is defined as Lc (cm), and a club inertia moment about the center of gravity of the club is defined as Ic (kg.Math.cm.sup.2). Isw is calculated by Equation (1) below. Ige is calculated by Equation (2) below.
Isw=Wc×(Lc+60).sup.2+Ic  (1)
Ige=Wc×(Lc).sup.2+Ic  (2)

A balanced club head includes an encasing with a face plate, a rear side, left and right side, a top side, and a bottom side, defining an interior, right and left inner longitudinal walls, a shaft aperture, a shaft receptacle, a notch in one of the walls, such that the balanced club head is configured to receive a golf shaft, such that the shaft receptacle is configured to receive a lower end of the golf shaft, which protrudes through the shaft aperture with the notch accommodating an angled position of the golf shaft, thereby creating a counter weight and balance that maximizes distance and provides greater accuracy of direction when mounted on a golf club.

A conventional length golf putter a first grip attached to the end of the shaft and a second grip attached to the shaft spaced from and below the first grip. The grips have matching frustoconical portions to create similar feel. The putter has a head with an alignment system to accommodate heel and toe putts.

A conventional length golf putter a first grip attached to the end of the shaft and a second grip attached to the shaft spaced from and below the first grip. The grips have matching frustoconical portions to create similar feel. The putter has a head with an alignment system to accommodate heel and toe putts.

Golf club heads are releasably engaged with shafts so that the club heads and shafts can be readily interchanged and/or so that the shaft position with respect to the club head can be readily changed. Assemblies for connecting the club head and shaft may include: a shaft adapter, a collet, a ferrule, and a club head having an interior chamber. The club head and shaft may be changed by releasing the securing system and exchanging the original parts with different parts.

Golf club heads are releasably engaged with shafts so that the club heads and shafts can be readily interchanged and/or so that the shaft position with respect to the club head can be readily changed. Assemblies for connecting the club head and shaft may include: a shaft adapter, a collet, a ferrule, and a club head having an interior chamber. The club head and shaft may be changed by releasing the securing system and exchanging the original parts with different parts.

A motion sensor package with an elastomer layer that encases the sensor electronics, including the sensors, a processor, an antenna, and a battery. The elastomer layer may provide shock isolation and water resistance to protect the enclosed electronics. Embodiments may also include an outer housing into which the elastomer encased package is installed. The outer housing may for example comprise two cylindrical sections that screw together to close the outer housing. In one or more embodiments part of the outer housing may be integrated into an item of sports equipment. Embodiments for golf may also include a golf club grip adapter that is inserted into the top of a grip, and which attaches to the outer housing containing the elastomer enclosed sensor package.

A grip device is disposed on a handle of a piece of equipment. The grip device includes a lower concave surface contacting the handle and a lower concave surface oriented away from the handle. An adhesive tape is wrapped around the handle and grip device in one embodiment. In another embodiment, an adhesive layer is disposed between the handle and grip device. The lower concave surface includes a first taper at an end of the grip device oriented toward a knob of the handle. The upper convex surface includes a second taper at an end of the grip device oriented away from the knob of the handle. The grip device bends to follow a curvature of the handle.