Energetics of Indoor Track Cycling in Trained Competitors

Abstract

Steady-state track VO₂ was estimated by means of the retroex-trapolation method in seventeen competitive male cyclists at speeds ranging from 28 to 43 km·h^-1. Peak VO₂ was also determined using an ergocycle multistage test (80 rev·min^-1). Results showed large VO₂ variations at similar speeds on the track (SEE > 10%Y; n = 17). Third degree regressions were the most accurate to describe the evolution of VO₂ with speed, while the units ml·kg^-0.667·min^-1 showed better correlations and lower dispersions than I·min^-1, ml.kg^-1·min^-1, and I·min^-1·m^-2. When categorized according to the Québec Cycling Federation ranking, (elites: n = 6; nonelites: n = 11), the elites tended to demonstrate a lower mean VO₂ for the range of velocities studied. The difference was, however, not statistically significant (P > 0.05). Inte-rindividual variations were reduced by expressing VO₂ and speed as relative percentages of maximal values in ten subjects:% MAP = 6.475 e exp [0.0274% MAS] where% MAP = track VO₂/laboratory peak VO₂, and%MAS = speed/speed associated with peak VO₂ on the track. No significant difference was observed between track and ergocycle peak VO₂ (P > 0.05), indicating the validity of the 80 rev.min^-1 protocol for laboratory evaluation of racing cyclists. The concept of cycling economy as a contributing factor to performance and applications of the% MAP -% MAS relationship are discussed.

Key words

cycling - VO₂ - speed - training intensities - performance