rrently affixed to a location that is appropriate for the prescribed exercise type, the user will move the sensor unit at this time, affixing or reaffixing the motion sensor by way of a clip, strap or magnet 523 to an item worn by the person 504 for example, clothing, wristband, belt or shoe, 506, a body part of the user for example a wrist or ankle or neck, or a movable portion of a piece of exer