title: Evidence for Acute Electrophysiological and Cognitive Changes Following Routine Soccer Heading.
abstract: BACKGROUND
  There is growing concern around the effects of concussion and sub-concussive impacts in sport. Routine game-play in soccer involves intentional and repeated head impacts through ball heading. Although heading is frequently cited as a risk to brain health, little data exist regarding the consequences of this activity. This study aims to assess the immediate outcomes of routine football heading using direct and sensitive measures of brain function.
  
  
  METHODS
  Nineteen amateur football players (5 females; age 22±3y) headed machine-projected soccer balls at standardized speeds, modelling routine soccer practice. The primary outcome measure of corticomotor inhibition measured using transcranial magnetic stimulation, was assessed prior to heading and repeated immediately, 24h, 48h and 2weeks post-heading. Secondary outcome measures were cortical excitability, postural control, and cognitive function.
  
  
  RESULTS
  Immediately following heading an increase in corticomotor inhibition was detected; further to these electrophysiological alterations, measurable reduction memory function were also found. These acute changes appear transient, with values normalizing 24h post-heading.
  
  
  CONCLUSIONS
  Sub-concussive head impacts routine in soccer heading are associated with immediate, measurable electrophysiological and cognitive impairments. Although these changes in brain function were transient, these effects may signal direct consequences of routine soccer heading on (long-term) brain health which requires further study.
authors: Physiology, Exercise and Nutrition Research Group, University of Stirling, Scotland, UK.
authors: Thomas G
authors: TG
authors: Di Virgilio
authors: Physiology, Exercise and Nutrition Research Group, University of Stirling, Scotland, UK.
authors: Angus
authors: A
authors: Hunter
authors: Psychology, University of Stirling, Scotland, UK.
authors: Lindsay
authors: L
authors: Wilson
authors: Department of Neuropathology, Queen Elizabeth University Hospital, Glasgow and Institute of Neuroscience and Psychology, University of Glasgow, Scotland, UK.
authors: William
authors: W
authors: Stewart
authors: Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, UK.
authors: Stuart
authors: S
authors: Goodall
authors: Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, UK; Water Research Group, Unit for Environmental Sciences and Management, North West University, Potchefstroom, South Africa.
authors: Glyn
authors: G
authors: Howatson
authors: Psychology, University of Stirling, Scotland, UK.
authors: David I
authors: DI
authors: Donaldson
authors: Psychology, University of Stirling, Scotland, UK. Electronic address: magdalena.ietswaart@stir.ac.uk.
authors: Magdalena
authors: M
authors: Ietswaart
mesh_terms: D000328:Adult; D056352:Athletes; D001924:Brain Concussion / Q000209:etiology / Q000503:physiopathology* / Q000523:psychology*; D000070642:Brain Injuries, Traumatic / Q000209:etiology / Q000503:physiopathology / Q000523:psychology; D003071:Cognition; D003072:Cognition Disorders / Q000209:etiology / Q000523:psychology; D004576:Electromyography; D055724:Electrophysiological Phenomena; D005260:Female; D006801:Humans; D008297:Male; D004856:Postural Balance; D012916:Soccer; D050781:Transcranial Magnetic Stimulation; D004561:Transcutaneous Electric Nerve Stimulation; D055815:Young Adult
keywords: Sports concussion; Sub-concussion; Transcranial magnetic stimulation; Traumatic brain injury