Ventilatory Threshold and Maximal Oxygen Uptake during Cycling and Running in Female Triathletes

Abstract

Maximal oxygen uptake (V̇O₂max) and the ventilatory threshold (T_vent) were measured during cycle ergometry (CE) and treadmill running (TR) in a group of 10 highly trained female triathletes. T_vent was defined as the V̇O₂ at which the ventilatory equivalent for oxygen increased without a marked rise in the ventilatory equivalent for carbon dioxide. Female triathletes achieved a significantly higher mean (±SE) relative V̇O₂max for running (63.6 ± 1.2 ml·kg^-1·min ^-1) than for cycling (59.9 ± 1.3 ml·kg·min^-1). When oxygen uptake measured at the ventilatory threshold was expressed as a percent of V̇O₂max, the mean value obtained for TR (74.0 ± 2.0% of V̇O₂max) was significantly greater than the value obtained for CE (62.7 ± 2.1% of V̇O₂max). This occurred even though the total training time and intensity were similar for the two modes of exercise. Female triathletes had average running and cycling V̇O₂max values that compared favorably with maximal oxygen uptake values previously reported for elite female runners and cyclists, respectively. However, mean running and cycling T_vent values (V̇O₂ @ T_vent as%V̇O₂max) were lower than recently reported values for single-sport athletes. The physiological variability between the triathletes studied and single-sport athletes may be attributed in part to differences in training distance or intensity, and/or to variations in the number of years of intense training in a specific mode of exercise. It was concluded that these triathletes were well-trained in both running and cycling, but not to the same extent as female athletes who only train and compete in running or cycling.

Key words

Female triathlete - ventilatory threshold - anaerobic threshold - maximal oxygen uptake