A golf club shaft stiffening device with a flexible tubular body including an inner circumference and a length forming a tubular cavity is described. The inner circumference of the shaft stiffening device is sized and configured to circumscribe and constrictively engage an outer surface of a shaft and to cause the shaft to have an increased stiffness characteristic, allow the location of a kick point to be modified or modify other characteristics of the golf club. The shaft stiffening device may be housed on various sections of the shaft and may be slidably adjusted or positioned on the shaft. An associated method for fitting a golf club with a shaft stiffening device is also described. The shaft stiffening devices may be provided in a kit to facilitate fitting of a golf club with appropriate shaft stiffening devices.

[0037] FIGS. 5B-5D illustratively show the golf club 199 with a shaft stiffening device 300A-300C housed on the low 400A, mid 400B, and high 400C sections of the shaft 190. FIGS. 5B-5D also demonstrate the effect shaft stiffening devices 300A-300C have on various golf club 199 characteristics including flex length 290B-290D and the location of the kick point 205B-205D. FIG. 5B illustratively shows the golf club 199 with shaft stiffening device 300A housed on the low section 400A of the shaft 190 adjacent to the golf club head end 100. The shaft stiffening device is constrictively engaged about the exterior of the shaft 190. The stiffening device 300A may be composed of a number of materials as described previously including rubbers, polymers, plastics and other materials. The shaft stiffening device 300A constrictively engaging the low section 400A of the shaft causes the region portion of the shaft radially inward of the shaft stiffening device to exhibit an increased stiffness characteristic down the length 330A between the ends 311A, 312A of the shaft stiffening device 300A. Here, the stiffness characteristics have been altered such that the shaft 190 is rigid in the low section 400A of the shaft of the golf club 199. Accordingly, the portion of the shaft that exhibits flex or bending can be changed as can the associated flex length 290B. Additionally, the kick point 205B is shifted upward further towards the high section 400C and the grip 195 of the golf club. FIG. 5C illustratively shows the golf club 199 with shaft stiffening device 300B housed on the mid section 400B of the shaft 190 of the golf club head 100. Similarly, the shaft stiffening device 300B is depicted through its constrictive engagement as causing the mid section 400B to exhibit increased stiffness characteristics and in particular fairly rigid characteristics. Accordingly, the shaft 190 now has two flex length regions 205C. Additionally, the shaft in the configuration of FIG. 5C also has a pair of kick points 205C on opposite sides of the shaft stiffening device. Lastly, FIG. 5D illustratively shows the golf club 199 with shaft stiffening device 300C housed on the high section 400C of the shaft 190. The high section 400C of the golf club shaft is shown as having an increased stiffness trait as the shaft in this region is illustrated as being held generally rigid by the shaft stiffening device 300C. Accordingly, flex lengths 290D extend down near golf club head 100 end of the golf club head 100 and at the grip 195 respectively. Also, the kick points 205D have varied locations.