title: Neuromuscular fatigue of the knee extensors during repeated maximal intensity intermittent-sprints on a cycle ergometer.
abstract: BACKGROUND
  We studied the time course of neuromuscular fatigue during maximal intensity intermittent-sprint cycling.
  
  
  METHODS
  Eight participants completed 10, 10-s sprints interspersed with 180 s of recovery. The power outputs were recorded for each sprint. Knee extensor maximum voluntary contraction (MVC) force, voluntary activation, and evoked contractile properties were recorded presprint, postsprint 5, and postsprint 10.
  
  
  RESULTS
  Total work over the 10 sprints decreased significantly (P < 0.05) and could be described by 2 linear relationships from sprints 1-5 compared with sprints 6-10. Participants had significantly (P < 0.05) lower MVC and twitch forces postsprint 5 compared with presprint. MVC, voluntary activation, and twitch force were decreased (P < 0.05) postsprint 10 compared with postsprint 5.
  
  
  CONCLUSIONS
  The maximal intermittent sprints induced neuromuscular fatigue. Neuromuscular fatigue in the first 5 sprints was mainly peripheral, whereas in the last 5 sprints it was both peripheral and central.
authors.affiliation: School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. 230 Elizabeth Avenue, John's, NL, Canada, A1C 5S7.
authors.forename: Gregory E P
authors.initials: GE
authors.lastname: Pearcey
authors.forename: Justin R
authors.initials: JR
authors.lastname: Murphy
authors.forename: David G
authors.initials: DG
authors.lastname: Behm
authors.forename: Dean C
authors.initials: DC
authors.lastname: Hay
authors.forename: Kevin E
authors.initials: KE
authors.lastname: Power
authors.forename: Duane C
authors.initials: DC
authors.lastname: Button
mesh_terms: D000293:Adolescent; D000328:Adult; D001642:Bicycling / Q000502:physiology*; D004576:Electromyography / Q000379:methods; D016552:Ergometry / Q000379:methods; D006801:Humans; D007717:Knee / Q000502:physiology*; D007719:Knee Joint / Q000502:physiology; D008297:Male; D009119:Muscle Contraction / Q000502:physiology*; D018763:Muscle Fatigue / Q000502:physiology*; D005082:Physical Exertion / Q000502:physiology; D055815:Young Adult
keywords: cycling; force; intermittent sprints; neuromuscular fatigue; voluntary activation