Time for action: the impact of fatigue and the presence of opponents on the perception of time during a 4-km cycling trial.

The perception of time elapsed is known to vary in accordance with exercise intensity and stress (1). An accurate perception of time may be an important component of pacing during exercise (1). Research has shown that the perception of time is altered during individual endurance exercise at a fixed rate of perceived exertion (RPE) (1). However, further complexities during most sport scenarios include the increase of fatigue over the course of competition, while the presence of opponents also impacts pacing and performance (2). The purpose of this study is therefore to examine the impact of fatigue and opponents on the perception on time in response to exercise. 13 active healthy adults (seven females, six males) completed four, 4-km trials on a Velotron cycling ergometer. Participants were asked to specify when 30 seconds had elapsed, while chronologic time was simultaneously measured using a stopwatch. This task was performed before, during (pseudo randomized at either 500m, 1500m or 2500m) and two minutes after finishing the trial. Visit 1 was a familiarization trial (FAM). Visits 2 to 4 involved the following conditions, in randomized order: 1) cycle alone with the goal of setting the fastest time, 2) cycle alongside a virtual opponent (evenly paced, finish time: 105% of FAM) with the goal of beating the virtual opponent, 3) cycle alongside a virtual opponent with the goal setting the fastest time. RPE was recorded at the start of the trial, at two pseudo randomized moments during the trial (at 1-km, 2-km or 3-km), and directly after finishing the trial. A 3 x 3 repeated measurement ANOVA (p<.05) was used to examine differences in the perception of time pre-, during- and post-exercise, and between the three conditions. Two one-way ANOVAs (p<.05) were used to examine differences in the inter-trial perception of time and RPE over the course of the trials. Participants perceived time as slower during exercise (27.14±6.71s) compared to pre- (31.78±6.83s) and post-exercise (31.13±7.48s) (F2, 24=4.99, p=0.02). There was no difference in the perception of time (F2, 24=0.15, p=0.864) between the conditions. RPE increased throughout the trials (F4, 152=271.70, p<0.001). There was no inter-trial difference in the perception of time (F2, 4=0.207, p=0.814). Time is perceived to move slower during exercise, compared to rest, indicating that participates felt it took longer than chronologic time. This indicates some education of time perception could be useful for accurate pacing. The perception of time returns back to pre-exercise level state after a short recovery period. An increase in perceived fatigue over the course of continued exercise, or the presence of an opponent, do not further impact the perception of time, indicating time perception may be based more on internal psychophysiological sensations of discomfort rather than extrinsic factors.

1. Edwards & McCormick. Physiol Behav.2017;180:98-102.
2. Konings et al. Physiol Behav.2016;158:1-5.