title: Reproducibility of a laboratory based 20-km time trial evaluation in competitive cyclists using the Velotron Pro ergometer.
abstract: The purpose of this study was to evaluate the reliability of a 20-km cycling time trial using the Velotron cycle ergometer in competitive cyclists. Twenty male cyclists (V.O (2max) = 68.5 +/- 3.6 ml . kg (-1) . min (-1); peak power (P (peak)) = 469 +/- 33 W) participated in this study. Each subject performed a V.O (2max) test and 3 separate 20-km time trials (TT1, TT2, and TT3). Data from trials were compared using a one-way ANOVA. Coefficients of variation (CV) and 95 % confidence intervals (CI) were calculated between trials. Values are mean +/- SD unless otherwise noted. Performance time T (tot) (30.03 +/- 1.24, 30.12 +/- 1.21, and 30.14 +/- 1.21 min) and mean absolute power (P (mean)) (326 +/- 35, 323 +/- 35, 322 +/- 34 Watts) were not significantly different across TT1 - TT3. P (mean) was highly related between TT1 - TT2 (r = 0.96; p < 0.01) and TT2 - TT3 (r = 0.97; p < 0.01). A low CV was also demonstrated between trials for P (mean) (TT1 - TT2 = 2.1 %, CI = 1.6 % to 3.1 %; TT2 - TT3 = 1.9 %, CI = 1.4 % to 2.8 %). P (peak) and P (mean) were both correlated to T (tot) in TT1 with P (mean) accounting for most of the variance in T (tot) (R (2) = 0.993). These data show that performance in a 20-km time trial using the Velotron ergometer is highly reproducible in competitive cyclists. Furthermore, the CV variance demonstrated between trials is comparable to that expected during actual performance in elite athletes.
authors.affiliation: Department of Human Kinetics, University of British Columbia, Vancouver, Canada. sporer@interchange.ubc.ca
authors.forename: B C
authors.initials: BC
authors.lastname: Sporer
authors.forename: D C
authors.initials: DC
authors.lastname: McKenzie
mesh_terms: D000328:Adult; D001642:Bicycling / Q000502:physiology*; D005080:Exercise Test / Q000295:instrumentation* / Q000379:methods*; D006801:Humans; D008297:Male; D010807:Physical Endurance; D015203:Reproducibility of Results