title: Physiological, Perceptual and Performance Responses Associated With Self-Selected Versus Standardized Recovery Periods During a Repeated Sprint Protocol in Elite Youth Football Players: A Preliminary Study.
abstract: To examine the physiological and perceptual responses of youth footballers to a repeated sprint protocol employing standardized and self-selected recovery.
  
  
  
  Eleven male participants (13.7 ± 1.1 years) performed a repeated sprint assessment comprising 10 × 30 m efforts. Employing a randomized cross-over design, repeated sprints were performed using 30 s and self-selected recovery periods. Heart rate was monitored continuously with ratings of perceived exertion (RPE) and lower body muscle power measured 2 min after the final sprint. The concentration of blood lactate was measured at 2, 5 and 7 min post sprinting. Magnitude of effects were reported using effect size (ES) statistics ± 90% confidence interval and percentage differences. Differences between trials were examined using paired student t tests (p < .05).
  
  
  
  Self-selected recovery resulted in most likely shorter recovery times (57.7%; ES 1.55 ± 0.5; p < .01), a most likely increase in percentage decrement (65%; ES 0.36 ± 0.21; p = .12), very likely lower heart rate recovery (-58.9%; ES -1.10 ± 0.72; p = .05), and likely higher blood lactate concentration (p = .08-0.02). Differences in lower body power and RPE were unclear (p > .05).
  
  
  
  Self-selected recovery periods compromise repeated sprint performance.
authors.affiliation: 1 Oriam: Scotland's Sports Performance Centre.
authors.forename: Neil
authors.initials: N
authors.lastname: Gibson
authors.affiliation: 2 Heriot-Watt University.
authors.forename: Callum
authors.initials: C
authors.lastname: Brownstein
authors.affiliation: 2 Heriot-Watt University.
authors.forename: Derek
authors.initials: D
authors.lastname: Ball
authors.affiliation: 3 University of Chester.
authors.forename: Craig
authors.initials: C
authors.lastname: Twist
mesh_terms: D000293:Adolescent; D054874:Athletic Performance / Q000502:physiology / Q000523:psychology; D015415:Biomarkers / Q000097:blood; D018592:Cross-Over Studies; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D019344:Lactic Acid / Q000097:blood; D008297:Male; D010465:Perception; D012146:Rest / Q000502:physiology / Q000523:psychology; D012420:Running / Q000502:physiology / Q000523:psychology; D012916:Soccer / Q000502:physiology / Q000523:psychology; D013997:Time Factors; D000067009:Youth Sports / Q000502:physiology / Q000523:psychology
chemical_list: D015415:Biomarkers; D019344:Lactic Acid