The availability of task-specific feedback does not affect 20 km time trial cycling performance or test-retest reliability in trained cyclists

Abstract Objectives This study examined the influence of the availability of task-specific feedback on 20 km time trial (20 T T) cycling performance and test-retest reliability. Design Thirty trained, club-level cyclists completed two 20 T T’s on different days, with (feedback, FB) or without (no-feedback, NFB) task-specific feedback (i.e., power output, cadence, gear and heart rate [HR]). Elapsed distance was provided in both conditions. Methods During trials, ergometer variables and HR were continuously recorded, and a rating of perceived exertion (RPE) was collected every 2 km. Data were analysed using linear mixed-effects models in a Bayesian framework, and Cohen’s d was calculated for standardised differences. The reliability of finish time and mean power output (PO) was determined via multiple indices, including intraclass correlations (ICC). Results Performance, pacing behaviour, and RPE were not statistically different between conditions. The posterior mean difference [95% credible interval] between TT1 and TT2 for FB and NFB was 10 seconds [-5, 25] and −2 seconds [-17, 14], respectively. In TT2, HR was statistically higher (∼8 b·min-1) in FB compared to NFB after 13 km (d = 2.08–2.25). However, this result was explained by differences in maximal HR. Finish time (FB: ICC = 0.99; NFB: ICC = 0.99) and mean power output (FB: ICC = 0.99; NFB: ICC = 0.99) in each condition were substantially reliable. Conclusions The availability of task-specific information did not affect 20 T T performance or reliability. Except for elapsed distance, task-specific feedback should be withheld from trained cyclists when evaluating interventions that may affect performance, to prevent participants from recalling previous performance settings.