Abstract: A sensing device is attached to a living subject that includes a first sensors for distinguishing lying, sitting, and standing positions. In another embodiment, sensor data is stored in a storage device as a function of time. Multiple points or multiple intervals of the time dependent data are used to direct a feedback mechanism to provide information or instruction in response to the time dependent output indicating too little activity, too much time with a joint not being moved beyond a specified range of motion, too many motions beyond a specified range of motion, or repetitive activity that can cause repetitive stress injury.