To obtain a golf club and a connecting member for a golf club shaft and a golf club head that can provide a flexibility in choice of reshafting to a user regardless of types of the golf club shaft and the golf club head and that can also provide excellent strength and/or appearance. A connecting member connects an inner-hosel-type golf club shaft and an over-hosel-type golf club head. The connecting member includes a hybrid structure combining different kinds of material.

To obtain a golf club and a connecting member for a golf club shaft and a golf club head that can provide a flexibility in choice of reshafting to a user regardless of types of the golf club shaft and the golf club head and that can also provide excellent strength and/or appearance. A connecting member connects an inner-hosel-type golf club shaft and an over-hosel-type golf club head. The connecting member includes a hybrid structure combining different kinds of material.

A universal swing training apparatus is provided that includes a sports-related implement and a slide mechanism. The implement includes a proximal section and a distal section that are spaced apart to form a gap there-between. The slide mechanism is inserted within this gap and is connected to the upper end of the proximal section and the lower end of the distal section. The slide mechanism includes a rail guide, a plurality of front ball bearings, a plurality of rear ball bearings, and a sliding rail assembly that are cooperatively configured to insure that this upper end and this lower end are coaxial when the sliding rail assembly is situated in a coaxial position on the rail guide, and permit a lateral shift of this lower end relative to this upper end during a swinging of the implement.

A universal swing training apparatus is provided that includes a sports-related implement and a slide mechanism. The implement includes a proximal section and a distal section that are spaced apart to form a gap there-between. The slide mechanism is inserted within this gap and is connected to the upper end of the proximal section and the lower end of the distal section. The slide mechanism includes a rail guide, a plurality of front ball bearings, a plurality of rear ball bearings, and a sliding rail assembly that are cooperatively configured to insure that this upper end and this lower end are coaxial when the sliding rail assembly is situated in a coaxial position on the rail guide, and permit a lateral shift of this lower end relative to this upper end during a swinging of the implement.

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.

Provided are the golf club shaft and the golf club for offering excellent feel of swing motions without demanding fine setting while keeping advantages of the short-sized golf club shaft. The golf club shaft includes a shaft body which extends in a longitudinal direction, and a gravity center shifting member attached to the shaft body for shifting a shaft gravity center toward a distal-end side in the longitudinal direction. In the case where the shaft body is cut to have a shaft full length of 43 inches or shorter, and positions of a distal-end portion and a proximal-end portion in the longitudinal direction are defined by percentage as 0% and 100%, respectively, a position of the shaft gravity center is set to be in a range from 39% to 45%.

Provided are the golf club shaft and the golf club for offering excellent feel of swing motions without demanding fine setting while keeping advantages of the short-sized golf club shaft. The golf club shaft includes a shaft body which extends in a longitudinal direction, and a gravity center shifting member attached to the shaft body for shifting a shaft gravity center toward a distal-end side in the longitudinal direction. In the case where the shaft body is cut to have a shaft full length of 43 inches or shorter, and positions of a distal-end portion and a proximal-end portion in the longitudinal direction are defined by percentage as 0% and 100%, respectively, a position of the shaft gravity center is set to be in a range from 39% to 45%.

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 resilient rod that provides adjustable directional resistance is disclosed. In one aspect of the invention, a resistance level may be determined based on a thickness of the rod and a position of an applied force with respect to a fulcrum point. In another aspect of the invention, at least one spine may be attached to the beam to increase a diameter of the beam along one axis. The resistance level may be determined based on the thickness of the rod, the position of the applied force and an orientation of the at least one spine with regard to the direction of the applied force. In other aspects of the invention, the resilient rods may be incorporated into a golf club that provides for adjustable resistance levels.