This study examined how, ventilatory threshold (VT), and cardiorespiratory responses during a simulated triathlon contributed to triathlon performance. Nine male trained triathletes conducted both maximal exercise tests and simulated triathlon test in a laboratory. Vo₂max and Vo₂ @VT during each exercise were determined by the former test. The latter tests consisted of flume-pool swimming (S), ergometer cycling (C) and treadmill running (R) as a continuous task. The exercise intensity and duration were 60% of Vo₂max during a swimming, cycling and running for 30,75 and 45 min, respectively. The index of cardiorespiratory responses during simulated triathlon was determined by the change ratios (⊿) of Vo₂, VE and HR between the 10 th min and last min at each stage.
　Results indicated that there were no significant correlations between triathlon performance (total time) and Vo₂max , between total time and Vo₂@VT. However, it was found that total time was significantly correlated to ⊿R-Vo₂ (r=0.670, P<0.05), ⊿R-VE (r=0.834, P<0.01), ⊿C-HR (r=0.753, P<0.05), and ⊿R-HR (r=0.704, P<0.05). These results demonstrated that small increments of Vo₂, VE and HR at latter stage during a simulated triathlon test were more important factors to determine the triathlon performance rather than Vo₂max and/ or anaerobic threshold in trained triathletes.

DESCENTE SPORTS SCIENCE Vol.17/THE DESCENTE AND ISHIMOTO MEMORIAL FOUNDATION FOR THE PROMOTION SPORTS SCIENCE