title: The assessment of neuromuscular fatigue during 120 min of simulated soccer exercise.
abstract: OBJECTIVE
  This investigation examined the development of neuromuscular fatigue during a simulated soccer match incorporating a period of extra time (ET) and the reliability of these responses on repeated test occasions.
  
  
  METHODS
  Ten male amateur football players completed a 120 min soccer match simulation (SMS). Before, at half time (HT), full time (FT), and following a period of ET, twitch responses to supramaximal femoral nerve and transcranial magnetic stimulation (TMS) were obtained from the knee-extensors to measure neuromuscular fatigue. Within 7 days of the first SMS, a second 120 min SMS was performed by eight of the original ten participants to assess the reliability of the fatigue response.
  
  
  RESULTS
  At HT, FT, and ET, reductions in maximal voluntary force (MVC; -11, -20 and -27%, respectively, P ≤ 0.01), potentiated twitch force (-15, -23 and -23%, respectively, P < 0.05), voluntary activation (FT, -15 and ET, -18%, P ≤ 0.01), and voluntary activation measured with TMS (-11, -15 and -17%, respectively, P ≤ 0.01) were evident. The fatigue response was robust across both trials; the change in MVC at each time point demonstrated a good level of reliability (CV range 6-11%; ICC2,10.83-0.94), whilst the responses identified with motor nerve stimulation showed a moderate level of reliability (CV range 5-18%; ICC2,10.63-0.89) and the data obtained with motor cortex stimulation showed an excellent level of reliability (CV range 3-6%; ICC2,10.90-0.98).
  
  
  CONCLUSIONS
  Simulated soccer exercise induces a significant level of fatigue, which is consistent on repeat tests, and involves both central and peripheral mechanisms.
authors.affiliation: Department of Sport, Exercise and Rehabilitation, Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, NE1 8ST, UK. stuart.goodall@northumbria.ac.uk.
authors.forename: Stuart
authors.identifier: http://orcid.org/0000-0001-9029-2171
authors.initials: S
authors.lastname: Goodall
authors.affiliation: Department of Sport, Exercise and Rehabilitation, Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, NE1 8ST, UK.
authors.forename: Kevin
authors.initials: K
authors.lastname: Thomas
authors.affiliation: Department of Sport, Exercise and Rehabilitation, Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, NE1 8ST, UK.|School of Human and Health Sciences, University of Huddersfield, Huddersfield, UK.
authors.forename: Liam David
authors.initials: LD
authors.lastname: Harper
authors.affiliation: Department of Sport, Exercise and Rehabilitation, Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, NE1 8ST, UK.
authors.forename: Robert
authors.initials: R
authors.lastname: Hunter
authors.affiliation: Department of Sport, Exercise and Rehabilitation, Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, NE1 8ST, UK.
authors.forename: Paul
authors.initials: P
authors.lastname: Parker
authors.affiliation: Institute of Cellular Medicine, Newcastle University, Newcastle, UK.
authors.forename: Emma
authors.initials: E
authors.lastname: Stevenson
authors.affiliation: Institute of Cellular Medicine, Newcastle University, Newcastle, UK.
authors.forename: Daniel
authors.initials: D
authors.lastname: West
authors.affiliation: Department of Sport, Health and Nutrition, Leeds Trinity University, Leeds, UK.
authors.forename: Mark
authors.initials: M
authors.lastname: Russell
authors.affiliation: Department of Sport, Exercise and Rehabilitation, Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, NE1 8ST, UK.|Water Research Group, School of Environmental Sciences and Development, Northwest University, Potchefstroom, South Africa.
authors.forename: Glyn
authors.initials: G
authors.lastname: Howatson
mesh_terms: D000328:Adult; D015444:Exercise; D006801:Humans; D008297:Male; D018763:Muscle Fatigue; D018482:Muscle, Skeletal / Q000294:innervation / Q000502:physiology*; D012916:Soccer / Q000502:physiology*
keywords: Brain; Central nervous system; Intermittent exercise; Muscle; Performance