Influence of accurate and inaccurate 'split-time' feedback upon 10-mile time trial cycling performance

The objective of the study is to examine the impact of accurate and inaccurate 'split-time' feedback upon a 10-mile time trial (TT) performance and to quantify power output into a practically meaningful unit of variation. Seven well-trained cyclists completed four randomised bouts of a 10-mile TT on a SRM (TM) cycle ergometer. TTs were performed with (1) accurate performance feedback, (2) without performance feedback, (3) and (4) false negative and false positive 'split-time' feedback showing performance 5% slower or 5% faster than actual performance. There were no significant differences in completion time, average power output, heart rate or blood lactate between the four feedback conditions. There were significantly lower (p <0.001) average (V) over dotO(2) (ml min(-1)) and (V) over dotE (l min(-1)) scores in the false positive (3,485 +/- 596; 119 +/- 33) and accurate (3,471 +/- 513; 117 +/- 22) feedback conditions compared to the false negative (3,753 +/- 410; 127 +/- 27) and blind (3,772 +/- 378; 124 +/- 21) feedback conditions. Cyclists spent a greater amount of time in a '20 watt zone' 10 W either side of average power in the negative feedback condition (fastest) than the accurate feedback (slowest) condition (39.3 vs. 32.2%, p <0.05). There were no significant differences in the 10-mile TT performance time between accurate and inaccurate feedback conditions, despite significantly lower average (V) over dotO(2) and (V) over dotE scores in the false positive and accurate feedback conditions. Additionally, cycling with a small variation in power output (10 W either side of average power) produced the fastest TT. Further psycho-physiological research should examine the mechanism(s) why lower (V) over dotO(2) and (V) over dotE scores are observed when cycling in a false positive or accurate feedback condition compared to a false negative or blind feedback condition.