title: Reproducibility of the blood lactate-running speed curve in horses under field conditions.
abstract: OBJECTIVE
  To examine the reproducibility of blood lactate-running speed curve parameters derived by a curve-fit equation and by linear interpolation from the results of 4-speed tests of sport horses under field conditions.
  
  
  METHODS
  Thoroughbreds completed 10 test pairs with 3 to 11 days between tests and retest.
  
  
  METHODS
  7 Thoroughbreds.
  
  
  METHODS
  The 4-speed test consisted of 4 runs over a distance of 2,110 m. Exercise intensity was increased by 1 m/s for each run. Blood lactate concentration measured after each run was plotted against running speed to determine the blood lactate-running speed relation. By means of the blood lactate-running speed relation, velocity inducing 2, 2.5, 3, 3.5, or 4 mM blood lactate concentration was calculated by a curve-fit equation and by linear interpolation.
  
  
  RESULTS
  The test-retest correlation coefficient of velocity inducing 2, 2.5, 3, 3.5, and 4 mM blood lactate concentration determined by curve-fit equation was 0.67, 0.78, 0.84, 0.86, and 0.86, respectively, and by linear interpolation was 0.42, 0.58, 0.77, 0.87, and 0.78, respectively. But the test-retest regression was equal to the line of identity only for velocity inducing 3.5 and 4 mM blood lactate concentration.
  
  
  CONCLUSIONS
  The reproducibility of velocity inducing 3.5 and 4 mM blood lactate concentration was sufficient to be used to compare horses and evaluate conditioning effects. This holds both methods of calculation of the parameters derived from the blood lactate-running speed relation.
authors.affiliation: Institut für Anatomie Physiologie und Hygiene der Haustiere, Katzenburgweg, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Guhl
authors.forename: A
authors.initials: A
authors.lastname: Lindner
authors.forename: P
authors.initials: P
authors.lastname: von Wittke
mesh_terms: D000818:Animals; D005260:Female; D006736:Horses / Q000502:physiology*; D007773:Lactates / Q000097:blood*; D008297:Male; D008954:Models, Biological; D010805:Physical Conditioning, Animal; D005082:Physical Exertion; D012044:Regression Analysis; D015203:Reproducibility of Results; D012420:Running; D013997:Time Factors
chemical_list: D007773:Lactates