A system, method, and apparatus for an athlete to variably control the flexibility and stiffness parameters of a piece of athletic equipment to select a desired performance characteristic of the equipment based on the stiffness parameter. According to certain embodiments discussed herein, an item of sporting equipment may be embedded, impregnated, lined, or encased using nitinol components, wherein the nitinol components may themselves be treated using a specific method in order to achieve the desired transformation results, as described below.