title: Anaerobic capacity as a determinant of performance in sprint skiing.
abstract: OBJECTIVE
  As cross-country sprint competitions rely on maximal-effort durations of ∼3 min, a significant anaerobic energy contribution is expected. Anaerobic energy production during supramaximal exercise has been estimated in different sports from the accumulated oxygen deficit (ΣO₂ deficit) but, to date, not in cross-country skiing. Therefore, this study investigated the relative contribution of the aerobic and anaerobic energy systems to performance in ski skating sprint time trials using V1 and V2 techniques.
  
  
  METHODS
  Twelve elite senior male cross-country skiers participated in the study (24 ± 3 yr, 183 ± 5 cm, 79 ± 7 kg, V˙O(2max) = 72 ± 3 mL·kg⁻¹·min⁻¹ or 5.7 ± 0.5 L·min⁻¹). Three submaximal trials (4°-6°), one V˙O(2max) test (8°), and one performance test (7°, 600 m) were performed both in the V1 and in the V2 ski skating technique on a roller ski treadmill.
  
  
  RESULTS
  ΣO₂ deficit was ∼60 mL·kg⁻¹ and contributed to ∼26% of the total energy release during the ∼170-s time trials. Low to moderate correlations (r = 0.09-0.51) were found between O₂ cost of skiing, fractional utilization of V˙O(2peak), fractional utilization, and 600-m time. However, a moderate to strong correlation was found between ΣO₂ deficit and 600-m time in both the V1 (r = -0.75) and the V2 tests (r = -0.64) (both P < 0.05). No significant differences were found between techniques according to 600-m time or physiological responses.
  
  
  CONCLUSIONS
  The contribution from anaerobic energy systems was ∼26% and seemed independent of technique. In a group of elite skiers, the difference in roller ski treadmill sprint performance is more related to differences in anaerobic capacity than maximal aerobic power and O₂ cost.
authors.affiliation: Norwegian Research Centre for Training and Performance, Department of Physical Performance, Norwegian School of Sport Sciences, Oslo, Norway. Thomas.losnegard@nih.no
authors.forename: Thomas
authors.initials: T
authors.lastname: Losnegard
authors.forename: Håvard
authors.initials: H
authors.lastname: Myklebust
authors.forename: Jostein
authors.initials: J
authors.lastname: Hallén
mesh_terms: D000328:Adult; D015308:Anaerobic Threshold / Q000502:physiology*; D054874:Athletic Performance / Q000502:physiology*; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D019344:Lactic Acid / Q000097:blood; D008297:Male; D010101:Oxygen Consumption / Q000502:physiology; D012865:Skiing / Q000502:physiology*; D055815:Young Adult
chemical_list: D019344:Lactic Acid