Effect Of Pedaling Feedback On 20-km Time Trial Gross Efficiency And Power Output

Abstract

INTRODUCTION: Gross efficiency (GE) is a crucial factor in endurance cycling performance. Elite cyclists have superior pedaling technique, sustaining a greater average power output (PO) through the pedaling cycle than non-elite cyclists. Previous studies have demonstrated that pedaling technique can be improved with visual feedback (FB), however, the effect of pedaling feedback on GE and PO has not been investigated. PURPOSE: Determine the effect of FB from pedaling technique software on GE and PO during a 20-km time trial completed with feedback (WF) and without feedback (WO). METHODS: Eight recreationally-trained males (39 ± 6 y, VO2peak: 47.5 ± 6.1 mL·kg-1·min-1 at 282 ± 43 W) with at least six months of consistent cycling or triathlon training completed three 20-km TT. The first TT served to familiarize subjects with the FB software and cycle ergometer. During the other two sessions, subjects completed the time trial in the fastest time possible in both WF and WO conditions completed in randomized order. For WF, subjects received feedback regarding the smoothness of their pedal stroke cycle and attempted to optimize their pedaling technique real-time. Both GE and PO were calculated at 25, 50, 75, and 100% completion time. Statistical analyses of GE and PO for all stages of both WO and WF were completed using a 2x4 repeated measures ANOVA. RESULTS: GE and PO tended to be greater in all stages of WF when compared to WO (GE: 25%: 20.2 vs. 19.1%, 50%: 19.0 vs. 16.9%, 75%: 19.0 vs. 17.1%, 100%: 19.7 vs. 19.0%) (PO: 25%: 195 vs. 194 W, 50%: 203 vs. 171 W, 75%: 203 vs. 195 W, 100%: 221 vs. 213 W), but none were statistically significant (GE p = 0.084, PO p = 0.119). The biggest differences in GE and PO between the WF and WO conditions were at 50 and 75% completion. CONCLUSIONS: The monitoring of pedaling technique with FB of pedaling technique during a 20-km TT may lead to an improvement in GE without a reduction in PO during a single session using FB.