Abstract: An exercise-diligence-encouragement and coaching system, providing a small and widely configurable position-sensing device to existing weightlifting machines which provide resistance by leveraging the weight of a rack of vertically-stacked incremental weights. The position-sensing device communicates with a mobile device kept in view of a user of the weightlifting machine, to provide live instructions to the user and track progress of the user over time and tailor future exercises. Location of the device, type of sensor used, power source, and method of communication are all variable.