title: Elite cross-country skiers do not reach their running VO2max during roller ski skating.
abstract: OBJECTIVE
  Cross-country skiers' VO2max is often measured during treadmill running. However, VO2max during treadmill skiing with the diagonal stride technique is higher, whereas it is lower during double poling, another classical style technique. How these values compare to VO2max during ski skating in elite cross country skiers is not known. Therefore, this study compared VO2max during treadmill uphill running and treadmill roller ski skating.
  
  
  METHODS
  Twenty-two males (21±2 years, 182±6 cm, 77±7 kg, VO2max running; 72.4±4.4 mL·kg-1·min-1) elite cross-country skiers and biathlon athletes underwent testing in both running and roller ski skating before (May) and at the end (October) of the preseason training.
  
  
  RESULTS
  From May to October VO2max increased during running (3.1±4.5%, P=0.003, Effect size; ES=0.44, small) but not during roller ski skating (1.8±5.6%, P=0.13, ES=0.24, small). In May the subjects' VO2max during running was 1.7±4.7% higher compared to during roller ski skating (P=0.08, ES=0.24, small) while in October this difference was 3.0±5.0 % (P<0.001, ES=0.49, small).
  
  
  CONCLUSIONS
  Elite cross-country skiers do not elicit higher VO2max during roller ski skating than during running and this relationship does not change during the pre-season training period.
authors.affiliation: Department of Physical Performance, Norwegian School of Sport Sciences, Oslo, Norway - Thomas.losnegard@nih.no.
authors.forename: T
authors.initials: T
authors.lastname: Losnegard
authors.forename: J
authors.initials: J
authors.lastname: Hallén
mesh_terms: D005080:Exercise Test; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008297:Male; D010101:Oxygen Consumption; D010806:Physical Education and Training; D012123:Pulmonary Ventilation; D012420:Running / Q000502:physiology*; D012865:Skiing / Q000502:physiology*; D055815:Young Adult