Does a standardised exercise protocol incorporating a cognitive task provoke postconcussion-like symptoms in healthy individuals?
Lee H., Sullivan SJ., Schneiders AG.
OBJECTIVES: To explore whether an exercise protocol, alone and in combination with two selected cognitive tasks related to working memory, provokes postconcussion-like symptoms in healthy individuals. DESIGN: Prospective single cohort semi-randomised crossover repeated measures (time×condition) design. METHODS: 36 healthy individuals completed three submaximal exercise protocol conditions, namely: exercise alone, exercise with the paced auditory serial addition task, and exercise with Tetris. Self-reported symptoms were measured before exercise and 1-min and 15-min after the cessation of each exercise protocol using the Sports Concussion Assessment Tool 2-Postconcussion symptoms scale. RESULTS: Analysis of variance indicated a significant increase in symptom scores over time (p<0.001), but no effect between conditions (p=0.371) or a significant time×condition interaction (p=0.444). CONCLUSIONS: The combination of working memory tasks and a symptom provoking submaximal exercise protocol did not have an additional effect on the provocation of self-reported symptoms in healthy individuals. Furthermore, the two distinct methods of cognitive load delivery, controlled (paced auditory serial addition task) and pragmatic (Tetris), did not lead to a differential symptom response. These findings provide an initial insight into the scientific foundations for the symptom provocation model that is integral to the currently accepted clinical postconcussion return-to-play protocol.