LAUSR

Objectives: The present study aims to investigate the effect of mentally demanding cognitive tasks on rowing performance in prepubertal athletes. Design: Randomised, counterbalanced and crossover. Method: Seventeen rowers, aged between 10 and 12 years, completed three separate testing sessions during which they performed three different cognitive tasks before completing a 1500 m time trial on the rowing ergometer. In the two experimental conditions, one hour of a standard cognitive task (Stroop task) and an arithmetic school test were used to elicit mental effort; in the control condition a time‐matched, not demanding activity was carried out (painting). Subjective workload and mood were measured before and after the treatments, and the motivation was recorded before the time‐trial. During the time trial, time, power, speed, cadence, heart rate and rate of perceived exertion were assessed. Results: The Stroop task and the arithmetic test were rated more mentally demanding (P < 0.001), effortful (P < 0.001) and frustrating (P = 0.001) than the control task, but the items fatigue (P = 0.437, P = 0.197) and vigour (P = 0.143, P = 1.000) after the cognitive tasks were not significantly different from the control. The performance of the time trial did not differ between conditions (time: P = 0.521; power: P = 0.208; speed: P = 0.341); physiological (P = 0.556) and perceptual (P = 0.864) measures recorded during the physical task were not affected by the conditions. Accordingly, pacing profiles (P = 0.312) and cadence (P = 0.062) did not differ between the conditions. Conclusions: Mentally demanding activities did not affect the subsequent physical performance in prepubertal athletes. HighlightsThe effects of a Stroop task and an arithmetic test on rowing performance in prepubertal children were evaluated.Stroop task and arithmetic test had great mental demand, effort and frustration.Stroop task and arithmetic test did not result in greater fatigue or lower vigour than the control task.Mentally demanding cognitive tasks did not affect time, pacing and cadence of 1500‐m rowing time trial.