Abstract: A start timing instructing device includes a sensor attachable to the body of a player to detect changes in angle and/or acceleration associated with a backswing movement of the player. A variable resistor sets a start timing associated with a predetermined angle and/or acceleration data and has a volume by which the set start timing is adjustable. A microprocessor calculates an angle and/or acceleration data of the backswing movement based on the detected angle and/or acceleration and generates a start timing instruction if the calculated angle and/or acceleration data meet the angle and/or acceleration data which have been set and adjusted through the variable resistor and the volume. The microprocessor controls a stimulator attached to the body of the player to generate a vibration, sound or electric stimulation upon receiving the start timing instruction so as to inform the player of the body start timing for the downswing.

Abstract: To provide a downswing assisting device in a golf swing In order to increase one's hitting force, since power is generated by the stretching and the contraction of muscles, by making a difference in the returning from being twisted of the upper and lower limbs, the timing of the returning from being twisted of the trunk is important and hence, the present technique adjusts the timing of the downswing for each player separately and conducts the downswing.

Abstract: In order to stabilize golf swing motion of a player, downswing motion that is the most important but difficult part in golf swing is streamlined. A moving object is set in a golf club. When the club is in a vertical position in a flow of its movement from the top of the swing to downswing, the moving object starts to fall by the player's kinetic energy and gravity. The player swings down the club while confirming the fall of the moving object and matching his/her motion to the vector of the object in a direction of the fall. This enables the player to perform an efficient downswing where the club is swung in a shortcut path. A more realistic club swing can be made when it is performed on a address mat where a stance and a distance of a ball are indicated. This can be achieved by a removable handle end portion.

Abstract: The present invention provides a practice golf ball for approach shots and putting practice for helping golfers to improve the precision of their approach shots and putting when they hit regular golf balls, from which the golfers receive the same feeling of hit as from a regular golf ball. The smaller practice ball has a heavy metal core covered with rubber and the outer surface is coated or covered with a coating or covering material or a surface finishing material. Its weight and resilience are established to give the same feelings of heaviness and hit as the regular golf ball. Using these balls in the practice of applying the club face to the balls toward the target using an approach shot club or a putter, golfers acquire a latent image of the practice golf ball. Thus, the regular golf ball appears to be larger than its actual size. In this manner, golfers become capable of precisely applying the club face to the golf ball and improving the precision of their approach shots and putting.

Abstract: In order to stabilize golf swing motion of a player, downswing motion that is the most important but difficult part in golf swing is streamlined. A moving object is set in a golf club. When the club is in a vertical position in a flow of its movement from the top of the swing to downswing, the moving object starts to fall by the player's kinetic energy and gravity. The player swings down the club while confirming the fall of the moving object and matching his/her motion to the vector of the object in a direction of the fall. This enables the player to perform an efficient downswing were the club is swung in a shortcut path. A more realistic club swing can be made when it is performed on a address mat where a stance and a distance of a ball are indicated. This can be achieved by a removable handle end portion.