Validity of Expired Gas Dynamics Model during Intermittent Load Exercise

抄録

The purpose of this study was to determine a predictive validity of an expired gas dynamics (EGD) model during intermittent exercise using by system dynamics, individually. Five healthy males performed an incremental exercise test to determine maximal oxygen uptake (VO₂max) and anaerobic threshold (AT). Subjects then undertook intermittent load tests with three degrees of intensity (60 %VO₂max, 80 %VO₂max and 100 %VO₂max) using cycle ergometer. The EGD model was constructed using the incremental load test data. Data obtained from intermittent load tests were used as validity criterion of simulation. In simulation of the EGD model, oxygen uptake (VO₂), carbon dioxide output (VCO₂) and lactate (La) showed significantly high determination coefficient to validity criterion (R2 > 0.84, P < .05). In the comparison of simulation errors, there were no significant differences in VO₂, VCO₂ and La during 60 %VO₂max intensity exercise. At recovery period of 80 %VO₂max and 100 %VO₂max intensities simulation errors of VO₂ and VCO₂ were significant. It was inferred that time constant of VO₂ kinetics was slowed down by effect of excess post-exercise oxygen consumption (EPOC). Conclusively, the EGD model for individual was valid and accurate predictor of VO₂, VCO₂ and La during moderate intermittent load exercise.