title: Oxygen uptake during repeated-sprint exercise.
abstract: OBJECTIVE
  Repeated-sprint ability appears to be influenced by oxidative metabolism, with reductions in fatigue and improved sprint times related to markers of aerobic fitness. The aim of the current study was to measure the oxygen uptake (VO₂) during the first and last sprints during two, 5 × 6-s repeated-sprint bouts.
  
  
  METHODS
  Cross-sectional study.
  
  
  METHODS
  Eight female soccer players performed two, consecutive, 5 × 6-s maximal sprint bouts (B1 and B2) on five separate occasions, in order to identify the minimum time (trec) required to recover total work done (Wtot) in B1. On a sixth occasion, expired air was collected during the first and last sprint of B1 and B2, which were separated by trec.
  
  
  RESULTS
  The trec was 10.9 ± 1.1 min. The VO₂ during the first sprint was significantly less than the last sprint in each bout (p<0.001), and the estimated aerobic contribution to the final sprint (measured in kJ) was significantly related to VO₂max in both B1 (r=0.81, p=0.015) and B2 (r=0.93, p=0.001). In addition, the VO₂ attained in the final sprint was not significantly different from VO₂max in B1 (p=0.284) or B2 (p=0.448).
  
  
  CONCLUSIONS
  The current study shows that the VO₂ increases from the first to the last of 5 × 6-s sprints and that VO₂max may be a limiting factor to performance in latter sprints. Increasing V˙O₂max in team-sport athletes may enable increased aerobic energy delivery, and consequently work done, during a bout of repeated sprints.
authors.affiliation: Institution of Health Sciences, Mid Sweden University, Sweden; School of Sport Science, Exercise and Health, The University of Western Australia, Australia. Electronic address: kerry.mcgawley@miun.se.
authors.forename: Kerry
authors.initials: K
authors.lastname: McGawley
authors.affiliation: School of Sport Science, Exercise and Health, The University of Western Australia, Australia; Institute of Sport, Exercise and Active Living (ISEAL), College of Sport and Exercise Science, Victoria University, Australia.
authors.forename: David J
authors.initials: DJ
authors.lastname: Bishop
mesh_terms: D000328:Adult; D000332:Aerobiosis; D003430:Cross-Sectional Studies; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D010101:Oxygen Consumption; D012420:Running / Q000502:physiology*; D012916:Soccer / Q000502:physiology; D055815:Young Adult
keywords: Accumulated oxygen deficit; Aerobic contribution; Football; Repeated-sprint ability; Soccer; Team sports