title: The Effects of a 6-Week Strength Training on Critical Velocity, Anaerobic Running Distance, 30-M Sprint and Yo-Yo Intermittent Running Test Performances in Male Soccer Players.
abstract: The objectives of this study were to examine the effects of a moderate intensity strength training on changes in critical velocity (CV), anaerobic running distance (D'), sprint performance and Yo-Yo intermittent running test (Yo-Yo IR1) performances.
  
  
  METHODS
  two recreational soccer teams were divided in a soccer training only group (SO; n = 13) and a strength and soccer training group (ST; n = 13). Both groups were tested for values of CV, D', Yo-Yo IR1 distance and 30-m sprint time on two separate occasions (pre and post intervention). The ST group performed a concurrent 6-week upper and lower body strength and soccer training, whilst the SO group performed a soccer only training.
  
  
  RESULTS
  after the re-test of all variables, the ST demonstrated significant improvements for both, YoYo IR1 distance (p = 0.002) and CV values (p<0.001) with no significant changes in the SO group. 30-m sprint performance were slightly improved in the ST group with significantly decreased performance times identified in the SO group (p<0.001). Values for D' were slightly reduced in both groups (ST -44.5 m, 95% CI = -90.6 to 1.6; SO -42.6 m, 95% CI = -88.7 to 3.5).
  
  
  CONCLUSIONS
  combining a 6-week moderate strength training with soccer training significantly improves CV, Yo-Yo IR1 whilst moderately improving 30-m sprint performances in non-previously resistance trained male soccer players. Critical Velocity can be recommended to coaches as an additional valid testing tool in soccer.
authors.affiliation: University of Greenwich, Department of Life and Sports Science, Kent, England.
authors.forename: Bettina
authors.initials: B
authors.lastname: Karsten
authors.affiliation: Texas Tech University Health Science Center, Clinical Research Institute, Lubbock, Texas, United States of America.
authors.forename: Eneko
authors.initials: E
authors.lastname: Larumbe-Zabala
authors.affiliation: University of Greenwich, Department of Life and Sports Science, Kent, England.
authors.forename: Gokhan
authors.initials: G
authors.lastname: Kandemir
authors.affiliation: Hacettepe University, Faculty of Sports Sciences, Ankara, Turkey.
authors.forename: Tahir
authors.initials: T
authors.lastname: Hazir
authors.affiliation: Westfälische Wilhelms-Universität Münster, Arbeitsbereich für Sportpädagogik, Münster, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Klose
authors.affiliation: University of Greenwich, Department of Life and Sports Science, Kent, England.
authors.forename: Fernando
authors.initials: F
authors.lastname: Naclerio
mesh_terms: D000328:Adult; D054874:Athletic Performance / Q000502:physiology*; D015444:Exercise / Q000502:physiology*; D006801:Humans; D008297:Male; D053580:Muscle Strength / Q000502:physiology*; D010807:Physical Endurance / Q000502:physiology; D055070:Resistance Training; D012420:Running; D012916:Soccer / Q000502:physiology*