title: Oxygen uptake kinetics and middle distance swimming performance.
abstract: OBJECTIVE
  The aim of this study was to determine whether V˙O(2) kinetics and specifically, the time constant of transitions from rest to heavy (τ(p)H) and severe (τ(p)S) exercise intensities, are related to middle distance swimming performance.
  
  
  METHODS
  Fourteen highly trained male swimmers (mean ± SD: 20.5 ± 3.0 yr; 75.4 ± 12.4 kg; 1.80 ± 0.07 m) performed an discontinuous incremental test, as well as square wave transitions for heavy and severe swimming intensities, to determine V˙O(2) kinetics parameters using two exponential functions.
  
  
  METHODS
  All the tests involved front-crawl swimming with breath-by-breath analysis using the Aquatrainer swimming snorkel. Endurance performance was recorded as the time taken to complete a 400 m freestyle swim within an official competition (T400), one month from the date of the other tests.
  
  
  RESULTS
  T400 (Mean ± SD) (251.4 ± 12.4 s) was significantly correlated with τ(p)H (15.8 ± 4.8s; r=0.62; p=0.02) and τ(p)S (15.8 ± 4.7s; r=0.61; p=0.02). The best single predictor of 400 m freestyle time, out of the variables that were assessed, was the velocity at V˙O(2max)vV˙O(2max), which accounted for 80% of the variation in performance between swimmers. However, τ(p)H and V˙O(2max) were also found to influence the prediction of T400 when they were included in a regression model that involved respiratory parameters only.
  
  
  CONCLUSIONS
  Faster kinetics during the primary phase of the V˙O(2) response is associated with better performance during middle-distance swimming. However, vV˙O(2max) appears to be a better predictor of T400.
authors.affiliation: Faculty of Human Kinetics, Technical University of Lisbon, Portugal. joanaf.reis@netcabo.pt
authors.forename: Joana F
authors.initials: JF
authors.lastname: Reis
authors.forename: Francisco B
authors.initials: FB
authors.lastname: Alves
authors.forename: Paula M
authors.initials: PM
authors.lastname: Bruno
authors.forename: Veronica
authors.initials: V
authors.lastname: Vleck
authors.forename: Gregoire P
authors.initials: GP
authors.lastname: Millet
mesh_terms: D000293:Adolescent; D054874:Athletic Performance / Q000502:physiology*; D002151:Calorimetry / Q000295:instrumentation; D006801:Humans; D008297:Male; D010101:Oxygen Consumption / Q000502:physiology*; D012044:Regression Analysis; D013550:Swimming / Q000502:physiology*; D055815:Young Adult