title: Does a standardised exercise protocol incorporating a cognitive task provoke postconcussion-like symptoms in healthy individuals?
abstract: OBJECTIVE
  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.
  
  
  METHODS
  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.
authors.affiliation: Centre for Physiotherapy Research, University of Otago, New Zealand; Neuroscience Research Australia (NeuRA), Australia; School of Medical Sciences, University of New South Wales, Australia. Electronic address: hopinlee@gmail.com.
authors.forename: Hopin
authors.initials: H
authors.lastname: Lee
authors.affiliation: Centre for Physiotherapy Research, University of Otago, New Zealand.
authors.forename: S John
authors.initials: SJ
authors.lastname: Sullivan
authors.affiliation: Centre for Physiotherapy Research, University of Otago, New Zealand; School of Human, Health and Social Sciences, Central Queensland University, Australia.
authors.forename: Anthony G
authors.initials: AG
authors.lastname: Schneiders
mesh_terms: D000293:Adolescent; D000328:Adult; D018592:Cross-Over Studies; D005080:Exercise Test / Q000379:methods*; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D008297:Male; D008570:Memory, Short-Term; D038223:Post-Concussion Syndrome / Q000175:diagnosis* / Q000523:psychology; D011446:Prospective Studies; D057566:Self Report; D013647:Task Performance and Analysis; D055815:Young Adult
keywords: Brain concussion; Cognitive load; Exercise; Postconcussion symptoms; Return-to-play