Abstract: A combined sensor-transducer with a calculator or computer is provided in which the sensor senses mechanical motions as in muscular exercising to provide a transduced pulse to the calculator or transducer to tally the number of muscular movments or by inserting a factor in the computer to read out the pulses in terms of calories or energy. An improved type of reed switch is provided for sensing mechanical motions in which a magnet is slidably supported near magnetically responsive metal lead wires, the magnetic flux with each movement of the slidable magnet bending the wires into conductive contact.