title: Energy expenditure of extreme competitive mountaineering skiing.
abstract: OBJECTIVE
  Multi-hour ski mountaineering energy balance may be negative and intake below recommendations.
  
  
  METHODS
  Athletes on the 'Patrouille des Glaciers' racecourses (17 on course Z, 27 km, +2,113 m; 11 on course A, 26 km, +1,881 m) volunteered. Pre-race measurements included body mass, stature, VO2max, and heart rate (HR) vs VO2 at simulated altitude; race measurements HR, altitude, incline, location, and food and drink intake (A). Energy expenditure (EE) was calculated from altitude corrected HR derived VO2.
  
  
  RESULTS
  Race time was 5 h 7 min ± 44 min (mean ± SD, Z) and 5 h 51 min ± 53 min (A). Subjects spent 19.2 ± 3.2 MJ (Z), respectively, 22.6 ± 2.9 MJ (A) during the race. Energy deficit was -15.5 ± 3.9 MJ (A); intake covered 20 ± 7 % (A). Overall energy cost of locomotion (EC) was 9.9 ± 1.3 J m(-1) kg(-1) (Z), 8.0 ± 1.0 J m(-1) kg(-1) (A). Uphill EC was 11.7 ± 1 J m(-1) kg(-1) (Z, 13 % slope) and 15.7 ± 2.3 J m(-1) kg(-1) (A, 19 % slope). Race A subjects lost -1.5 ± 1.1 kg, indicating near euhydration. Age, body mass, gear mass, VO2max and EC were significantly correlated with performance; energy deficit was not.
  
  
  CONCLUSIONS
  Energy expenditure and energy deficit of a multi-hour ski mountaineering race are very high and energy intake is below recommendations.
authors.affiliation: Institute of Sports Sciences and Department of Physiology, Faculty of Biology and Medicine, University of Lausanne, Géopolis, Campus Dorigny, 1015, Lausanne, Switzerland.
authors.forename: Caroline
authors.initials: C
authors.lastname: Praz
authors.forename: Bertrand
authors.initials: B
authors.lastname: Léger
authors.forename: Bengt
authors.initials: B
authors.lastname: Kayser
mesh_terms: D000328:Adult; D003163:Competitive Behavior / Q000502:physiology*; D004734:Energy Metabolism; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009051:Mountaineering / Q000502:physiology*; D012865:Skiing / Q000502:physiology*