Abstract
The purpose of this study was to determine the influence of starting strategy on time
trial performance in the heat. Eleven endurance trained male cyclists (30±5 years,
79.5±4.6 kg, V˙O2max 58.5±5.0 ml.kg.−1 min−1) performed four 20-km time trials in the heat (32.7±0.7°C and 55% relative humidity).
The first time trial was completed at a self-selected pace (SPTT). During the following
time trials, subjects performed the initial 2.5-km at power outputs 10% above (10%
ATT), 10% below (10% BTT) or equal (ETT) to that of the average power during the initial
2.5-km of the self-selected trial; the remaining 17.5-km was self-paced. Throughout
each time trial, power output, rectal temperature, skin temperature, heat storage,
pain intensity and thermal sensation were taken. Despite significantly (P<0.05) greater
power outputs for 10% BTT (273±45W) compared with the ETT (267±48W) and 10% ATT (265±41W)
during the final 17.5-km, overall 20-km performance time was not significantly different
amongst trials. There were no differences in any of the other measured variables between
trials. These data show that varying starting power by ±10% did not affect 20 km time
trial performance in the heat.
Key words
pacing strategy - power - thermoregulation - bicycling - hyperthermia
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Correspondence
C. R. AbbissBSc. Sports Science
School of Exercise
Biomedical and Health Sciences
Edith Cowan University
100 Joondalup drive
6168 Perth
Australia
Phone: +61/8/6304 51 56
Fax: +61/8/6304 50 36
Email: c.abbiss@ecu.edu.au