To evaluate the exercise performance of the time constant in the VO_2-kinetics in female athletes, we made examination of VO_2 max and the oxgen uptake kinetics (VO_2) during treadmill running (seven females) or walking (eight females). In the study of the treadmill running, the time constant of the VO_2-kinetics was significantly correlated with VO_2 max. In the study of the treadmill walking, however the time constant of the VO_2-kinetics was not significantly correlated with VO_2 max. Our results suggest that the time constant of VO_2 kinetics may perform something different from anaerobic threshold or VO_2 max that are widely used as exercise performance
