title: Variation in heart rate and blood lactate concentration in freestyle kytesurfing.
abstract: OBJECTIVE
  The aim of this paper was to evaluate the physiological demands of freestyle kitesurfing.
  
  
  METHODS
  Ten elite subjects performed an incremental running test on a treadmill and a three 7 min simulated freestyle heats of kitesurfing in MW (Midwind) condition ranging from 15 to 22 knots. Oxygen uptake (VO(2)) was estimated from the heart rate (HR) recorded during the freestyle trial using the individual HR-VO(2) relationship determined during the incremental test. Blood lactate concentration [Lab] was measured at rest and 3 min after the exercise completion. 3 experienced kitesurfers acted as judges to better simulate competition conditions.
  
  
  RESULTS
  Linear relationship was demonstrated between scores and % HR(max) on water (r=-0.764, P<0.05), HR(max) on water (r=-0.684, P<0.05) estimated VO(2) on water (r=-0.724, P<0.05), HR on water (r=0.709, P<0.05), % VO(2) on water (r=0.740, P<0.05), final [Lab] (r=-0.884, P<0.05), anaerobic threshold (AT) (r=0.836, P<0.05), HR in AT (r=0.748, P<0.05) and ranking (r=-0,924, P<0.05), mean HR and estimated VO(2) values represented, respectively 85.4±3.0% of maximal heart rate and 80.0±4.5% of maximal oxygen uptake. Mid values for [Lab] were observed at the end of crossing trial (5.2±0.8 mmol L(-1)).
  
  
  CONCLUSIONS
  This first analysis of freestyle kitesurfing suggests that the energy demand is sustained by both aerobic and anaerobic metabolism during a MW condition and freestyle event of kitesurfing.
authors.affiliation: Departament of Sports and Information Technology, Pablo de Olavide University, Sevilla, Spain. acamps@upo.es
authors.forename: A
authors.initials: A
authors.lastname: Camps
authors.forename: F
authors.initials: F
authors.lastname: Vercruyssen
authors.forename: J
authors.initials: J
authors.lastname: Brisswalter
mesh_terms: D000328:Adult; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D019344:Lactic Acid / Q000097:blood*; D008297:Male; D010101:Oxygen Consumption / Q000502:physiology; D013177:Sports / Q000502:physiology*; D055815:Young Adult
chemical_list: D019344:Lactic Acid