Abstract

INTRODUCTION: Cycling at the highest sustainable intensity (i.e. isolated time-trial power output) is suggested as the best strategy to optimise sprint-distance triathlon performance (Suriano & Bishop, 2010, Eur J Appl Physiol, 110, 4:753-760). However, it is unclear how expectations, beliefs and perceptions influence the effectiveness of aggressive mid-event pacing during multi-modal endurance events. Taylor & Smith (2014, Physiol Behav, 133:45-52) suggest meaningful changes in triathlon performance may result from deceptive run pacing. However, it is yet to be determined whether deceptively aggressive bike pacing allows triathletes to maximise their sustainable intensity in this discipline, without the impairments in run performance typically associated with this strategy. It is also evident that the importance of different perceptual responses to pacing and so-called ‘reserve’ access during multi-modal exercise remains unclear. This study therefore examined the effects of deceptively aggressive bike pacing on sprint-distance triathlon performance and associated perceptual responses.

METHODS: Ten non-elite, competitive male triathletes completed three separate simulated sprint-distance triathlons (0.75 km swim, 500 kJ bike, 5 km run), the first of which established ‘baseline’ (i.e. personal best) performance (BL). During the remaining two trials athletes maintained a cycling power output 5% greater than BL, before completing the run as quickly as possible. However, participants were informed of this aggressive cycling strategy before and during only one of the two trials (HON). Prior to the alternate trial (DEC), participants were misinformed that mean cycling power output would equal that of BL, with on-screen feedback manipulated to display power output 5% below its true value. In addition to performance measures, ratings of perceived exertion (i.e. ‘global’ RPE), effort, muscular pain, breathlessness, thermal discomfort, affect and arousal were recorded throughout each trial.

RESULTS: Making triathletes aware of aggressive cycle pacing (HON) led to impaired run and overall performance (1350 ± 135 and 4356 ± 384 s, respectively) relative to DEC (1333 ± 129 and 4339 ± 395 s, respectively). However, there were no significant differences between trials in perceptual responses during swimming, cycling or running.

CONCLUSION: Expectations and beliefs can have a practically meaningful effect on triathlon pacing and performance, although the importance of different psychophysiological and emotional responses remains unclear. Whilst these findings are conducive with some form of ‘template’ being used by multi-sport athletes to interpret psychophysiological and emotional strain, they suggest that individual constructs such as RPE and affect may be less closely tied with pacing than has been inferred previously.