title: Physiological effects of technique and rolling resistance in uphill roller skiing.
abstract: OBJECTIVE
  The double pole technique (DP) has been shown to be more economical than the V1 skate technique (V1 ) on flat terrain. The objective of the present study was to compare these two techniques during uphill roller skiing. In addition, the physiological effects of changing roller ski rolling resistance was examined for V1.
  
  
  METHODS
  Five female and five male competitive cross-country skiers roller skied 4-min bouts on a 5.2% incline while physiological measurements were made.
  
  
  RESULTS
  Oxygen uptake (VO2) values averaged 8% greater (P = 0.0004) with V1, whereas rating of perceived exertion (RPE) and blood lactate concentrations were higher (P < or = 0.002) with DP. Doubling the dynamic friction coefficient of the roller skis, which increased external power output by 16-17%, resulted in VO2 values with V1 that averaged 13% higher (P = 0.0006). This magnitude of change in roller ski rolling resistance did not cause a statistical change in the relationship of VO2 with RPE.
  
  
  CONCLUSIONS
  These findings suggest that 1) grade has little effect on relative economies of DP and V1, possibly because of a lower effectiveness of force application with V1 when going uphill, and 2) large differences in roller ski rolling resistance should have no effect on the cardiovascular training adaptations that result from uphill roller skiing with V1.
authors.affiliation: Department of Physical Medicine, The Medical College of Wisconsin and VA Medical Center, Milwaukee 53295, USA. hoffman.martin_d@milwaukee.va.gov
authors.forename: M D
authors.initials: MD
authors.lastname: Hoffman
authors.forename: P S
authors.initials: PS
authors.lastname: Clifford
authors.forename: A C
authors.initials: AC
authors.lastname: Snyder
authors.forename: K P
authors.initials: KP
authors.lastname: O'Hagan
authors.forename: S W
authors.initials: SW
authors.lastname: Mittelstadt
authors.forename: M M
authors.initials: MM
authors.lastname: Roberts
authors.forename: H A
authors.initials: HA
authors.lastname: Drummond
authors.forename: S E
authors.initials: SE
authors.lastname: Gaskill
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D019344:Lactic Acid / Q000097:blood; D008297:Male; D010101:Oxygen Consumption / Q000502:physiology; D010465:Perception / Q000502:physiology; D012865:Skiing / Q000502:physiology*
chemical_list: D019344:Lactic Acid