Abstract
This study aimed to assess the level of agreement between internal (i.e., oxygen uptake,
heart rate, or ratings of perceived exertion) and external load markers (power output)
at critical power intensity, compared to the first ventilatory threshold, respiratory
compensation point, and maximum oxygen uptake derived from the cardiopulmonary exercise
test, and estimate critical power from values derived from the cardiopulmonary exercise
test in trained cyclists. Fourteen (13 males and 1 female) road master cyclists completed
a cardiopulmonary exercise test to determine the first ventilatory threshold, respiratory
compensation point, and maximum oxygen uptake. On a subsequent day, they completed
three maximal time-trial tests to estimate critical power and W’. Associated physiological
and perceptual values at critical power were estimated from linear regressions applied
to the cardiopulmonary exercise test results. Internal and external markers significantly
(p<0.05) increased from the first ventilatory threshold to the respiratory compensation
point and then maximum oxygen uptake. There were no significant differences between
internal and external markers at the respiratory compensation point vs. critical power
with strong correlations between responses. However, there was a mean bias for responses
at respiratory compensation point markers to overestimate some responses at critical
power (power output and oxygen uptake by ~8%). This study shows that critical power
can be estimated from a single cardiopulmonary exercise test. While the respiratory
compensation point is not a reliable critical power substitute, predictive equations
improve its estimation for more precise prescriptions in trained cyclists.
Keywords
Workload - training - intensity - distribution - volume - master cyclist
