Reproducibility of a laboratory-based 40-km cycle time-trial on a stationary wind-trainer in highly trained cyclists

The purpose of the present study was to examine the reproducibility of laboratory-based 40-km cycle time-trial performance on a stationary wind-trainer. Each week, for three consecutive weeks, and on different days, forty-three highly trained male cyclists (x̄ ± SD; age = 25 ± 6 y; mass = 75 ± 7 kg; peak oxygen uptake [V̇O 2peak] = 64.8 ± 5.2 ml x kg-1 x min-1) performed: 1) a V̇O2peak test, and 2) a 40-km time-trial on their own racing bicycle mounted to a stationary wind-trainer (Cateye - Cyclosimulator). Data from all tests were compared using a one-way analysis of variance. Performance on the second and third 40-km time-trials were highly related (r=0.96; p < 0.001), not significantly different (57:21 ± 2: 57 vs. 57:12 ± 3:14 min:s), and displayed a low coefficient of variation (CV)=0.9 ± 0.7%. Although the first 40-km time-trial (58:43 ± 3: 17 min:s) was not significantly different from the second and third tests (p = 0.06), inclusion of the first test in the assessment of reliability increased within-subject CV to 3.0 ± 2.9%. 40-km time-trial speed (km x h -1) was significantly (p < 0.001) related to peak power output (W; r = 0.75), V̇O2peak (1 x min-1; r = 0.53), and the second ventilatory turnpoint (1 x min-1; r = 0.68) measured during the progressive exercise tests. These data demonstrate that the assessment of 40-km cycle time-trial performance in well-trained endurance cyclists on a stationary wind-trainer is reproducible, provided the athletes perform a familiarization trial.