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Microcomputer servo-controlled bicycle ergometer system for psychophysiological research.

A R Laperriere·D H VanDercar·L Y Shyu·M F Ward·P M McCabe·A C Perry·P E Mosher·N Schneiderman
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Abstract

Steady state exercise is widely used for psychophysiological studies in which a constant heart rate at a predetermined level is desired. We have developed a microcomputer servo-controlled bicycle ergometer system that can be used for administering steady state exercise. Fourteen healthy male subjects, with a wide range of fitness levels (measured by VO2max) were exercised to either a fixed workload (130 watts) or a predetermined heart rate level (servo-heart rate) of 122 bpm (i.e., 65% of maximum calculated heart rate for the sample). Servo-heart rate was implemented using a feedback loop that automatically adjusted workload to compensate for immediate variations in heart rate, resulting in a more consistent heart rate. Heart rate varied from the predetermined value by 17 bpm during fixed workload but only 3 bpm during servo-heart rate (p less than .05). Therefore, by using the microcomputer servo-controlled bicycle ergometer, heart rate was maintained at a predetermined level regardless of the subject's fitness level. VO2max and workload during servo-heart rate were significantly correlated (r = .85, p less than .05). Therefore, the workload necessary to maintain heart rate at a constant level may provide an approximate index of aerobic fitness level.

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AdultExercise TestHeart RateHumansMaleMicrocomputersPsychophysiologyJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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BibTeXRIS

A R Laperriere, D H VanDercar, L Y Shyu, M F Ward, P M McCabe, A C Perry, P E Mosher, N Schneiderman. 1989. Microcomputer servo-controlled bicycle ergometer system for psychophysiological research.. https://doi.org/10.1111/j.1469-8986.1989.tb03157.x

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