Body building goes high-tech

The improvement in technology and the increased preoccupation-at least in the US-with personal fitness is evident in four basic categories of home equipment: electronic exercise machines, such as bicycles and rowing machines; bodily function monitors that measure blood pressure and pulse; pain control devices that use ultrasound and vibration; and stress management systems that depend on biological feedback from the skin. The newest so-called smart machines rely on electronics to calculate in real time and to display digitally and in LED graphics the rate of pedaling or running (speedometer), the elapsed time (clock) and/or distance (odometer), the amount of work being done (ergometer), and the number calories expended (calorimeter). Often these microprocessor-controlled machines can vary the intensity of a workout, remember prerecorded workout patterns, and record and print workout performances. A number of currently available products are described.