Acute stress does not influence the learning of a precise manual task: A randomized clinical trial

Acute stress is frequent in sports and rehabilitation contexts and can impact cognitive processes essential for motor learning. This study aimed to investigate the influence of induced acute stress on the learning of a precise manual task, examining its effect on five key parameters of fine motor control: trajectory error, trajectory error direction, time error, tracing accuracy, and task accuracy. A double-masked, randomized clinical trial with 62 participants (average age 20.65 ± 2.54 years; 39 females; 23 males) was conducted. To examine the effects of stress, participants were assigned to either a stress or a control group through stratified randomization by sex. Initially, all participants underwent the Maastricht Acute Stress Test (in its acute stress and control versions, respectively). Subsequently, they performed the precise manual task on a graphic tablet at three stages of the learning process: acquisition, short-term retrieval, and long-term retrieval. Electrodermal activity and heart rate variability were recorded to assess stress induction. Data analysis from 30 stress group participants and 25 control group participants revealed no statistically significant differences between groups in any of the variables studied at the three learning stages. Both groups exhibited statistically significant improvements in time error, trajectory error direction, and tracing accuracy during both short-term and long-term retrieval compared to acquisition. Our findings suggest that acute physical and psychological stress does not markedly impair learning a precise manual task of adhering to a specific trajectory and pace among young adults.