Abstract: An apparatus for measuring heart rate is provided which comprises a sensor for generating a signal which includes the biopotential signal produced by a heart. This signal is filtered, amplified and digitized. A microcomputer autocorrelates the digitized signal. A plurality of signal indication routines then scan the autocorrelated output for the presence of periodic signals. Each of the signal indication routines uses different search criteria, such as peak and waveform detection, and generates a candidate heart rate. An arbitrator then selects one of the candidate heart rates according to predetermined criteria. These criteria include the value of previously selected heart rates.

Abstract: In an exercise machine where an electric motor is used to simulate a weight stack a more realistic feel plus stability of operation is achieved by compensating the torque output of the motor for the mechanical characteristics of the machine including inertia, friction and gravitational effects on the user interface. Also by controlling the motor so as to increase its output torque as a function of the displacement of the user interface, it is possible to produce a measure of the user's strength. A heavy negative feature which may be selected by the user is provided as well. The exercise machine additionally includes a computer control which allows a pyramid type exercise program to be implemented.

Abstract: A control system for a health club which stores user records including user activity data in order to monitor and control use of the club's facilities. A central controller includes a memory for storing the user records including attendance data and accounting data, and a main control which is responsive to the user record data for determining whether a user is authorized to use the club's facilities. The central controller is coupled to various club facilities and equipment such as a computerized scale to prevent use thereof if a user is not authorized. The central controller also stores user history data such as user weight data for the computerized scale to alleviate data storage problems.