Pacing Behavior Development: The Role of Task Experience and the Presence of Competitors.

Introduction: Self-regulation of effort during exercise (i.e., pacing) is a determinant of exercise performance, which develops during childhood and adolescence. Yet the various aspects of pacing under development, such as the capability to use task experience and retain the task goal in the presence of other competitors, have remained relatively unexplored.

Methods: Nine adolescents (14.9 ± 2.1 yr old) and 14 adults (24.2 ± 3.2 yr old) completed four 4-km cycling trials in a well-controlled laboratory setting. After one familiarization visit, trials were performed in random order: alone, with the goal to finish the trial as fast as possible (AloneTime), with a competitor and the same goal (CompTime), or with a competitor and the goal to finish first (CompFirst). Within each age-group, repeated-measures ANOVA ( P < 0.05) examined the differences in the estimated task duration, pacing behavior (distribution of mean power output per 500 m), and performance (finish time) between visits (4) or conditions (3).

Results: In contrast to adults ( P < 0.05, ηp2 > 0.20), adolescents did not exhibit a change in estimation of task duration, pacing behavior, or performance over repeated visits ( P > 0.05, ηp2 < 0.10). Adolescents altered their pacing behavior in the presence of a competitor independent of the task goal (CompTime and CompFirst), whereas adults only demonstrated this alteration when instructed to finish first (CompFirst).

Conclusions: Adolescents are still developing the capability 1) to use experience from previous tasks to adjust their pacing behavior and 2) to inhibit the intuitive action of engaging with the competitor to retain the more abstract task goal of finishing the trial as fast as possible. These findings establish novel experimental evidence for the underpinnings of pacing behavior development.