Microcomputer servo-controlled bicycle ergometer system for psychophysiological research.
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.
Laperriere
A R
AR
VanDercar
D H
DH
Shyu
L Y
LY
Ward
M F
MF
McCabe
P M
PM
Perry
A C
AC
Mosher
P E
PE
Schneiderman
N
N
D000328:Adult; D005080:Exercise Test / Q000295:instrumentation*; D006339:Heart Rate; D006801:Humans; D008297:Male; D008838:Microcomputers; D011603:Psychophysiology / Q000295:instrumentation*