A controller of a training system is disclosed. In at least one embodiment of the invention, a controller defines an inner curved surface and includes a strap or clip so that the controller may be worn by the user comfortably and securely on either the backside of the hand, on the fingers, in the palm of the hand, on a wrist, arm or leg. The controller includes programmable control elements that allow a user to specify what functions are activated on a trainer by selection or depression of the control elements. In one embodiment, the controller may be programmed via a remote computing unit such as a computer or a smart phone. Alternatively, the controller can be programmed manually.
