title: The physiological and biomechanical differences between double poling and G3 skating in world class cross-country skiers.
abstract: BACKGROUND
  The current study compared differences in cycle characteristics, energy expenditure and peak speed between double poling (DP) and G3 skating.
  
  
  METHODS
  Eight world class male sprint skiers performed a 5-min submaximal test at 16 km h(-1) and an incremental test to exhaustion at a 5% incline during treadmill roller skiing with two different techniques: DP where all propulsion comes from poling, and G3 skating where leg skating is added to each double poling movement. Video analyses determined cycle characteristics; respiratory parameters and blood lactate concentration determined the physiological responses.
  
  
  RESULTS
  G3 skating resulted in 16% longer cycle lengths at 16% lower cycle rates, whereas oxygen uptake was independent of technique during submaximal roller skiing. The corresponding advantages for G3 skating during maximal roller skiing were reflected in 14% higher speed, 30% longer cycle length at 16% lower cycle rate and 11% higher peak oxygen uptake (all p < 0.05).
  
  
  CONCLUSIONS
  Compared to DP approximately 14% higher speed was achieved when leg push-offs were added in G3 skating. This was done by major increases in cycle lengths at slightly lower cycle rates and a higher aerobic energy delivery. However, the oxygen uptake for a given submaximal speed was not affected by technique although higher cycle rate was used in DP.
authors.affiliation: Department of Neuroscience, Center for Elite Sports Research, Norwegian University of Science and Technology, 7491, Trondheim, Norway, oyvind.sandbakk@svt.ntnu.no.
authors.forename: Øyvind
authors.initials: Ø
authors.lastname: Sandbakk
authors.forename: Stig
authors.initials: S
authors.lastname: Leirdal
authors.forename: Gertjan
authors.initials: G
authors.lastname: Ettema
mesh_terms: D000328:Adult; D001696:Biomechanical Phenomena; D006801:Humans; D008297:Male; D010101:Oxygen Consumption; D012865:Skiing / Q000502:physiology*