title: Sex and age-related differences in performance in a 24-hour ultra-cycling draft-legal event - a cross-sectional data analysis.
abstract: BACKGROUND
  The purpose of this study was to examine the sex and age-related differences in performance in a draft-legal ultra-cycling event.
  
  
  METHODS
  Age-related changes in performance across years were investigated in the 24-hour draft-legal cycling event held in Schötz, Switzerland, between 2000 and 2011 using multi-level regression analyses including age, repeated participation and environmental temperatures as co-variables.
  
  
  RESULTS
  For all finishers, the age of peak cycling performance decreased significantly (β = -0.273, p = 0.036) from 38 ± 10 to 35 ± 6 years in females but remained unchanged (β = -0.035, p = 0.906) at 41.0 ± 10.3 years in males. For the annual fastest females and males, the age of peak cycling performance remained unchanged at 37.3 ± 8.5 and 38.3 ± 5.4 years, respectively. For all female and male finishers, males improved significantly (β = 7.010, p = 0.006) the cycling distance from 497.8 ± 219.6 km to 546.7 ± 205.0 km whereas females (β = -0.085, p = 0.987) showed an unchanged performance of 593.7 ± 132.3 km. The mean cycling distance achieved by the male winners of 960.5 ± 51.9 km was significantly (p < 0.001) greater than the distance covered by the female winners with 769.7 ± 65.7 km but was not different between the sexes (p > 0.05). The sex difference in performance for the annual winners of 19.7 ± 7.8% remained unchanged across years (p > 0.05). The achieved cycling distance decreased in a curvilinear manner with advancing age. There was a significant age effect (F = 28.4, p < 0.0001) for cycling performance where the fastest cyclists were in age group 35-39 years.
  
  
  CONCLUSIONS
  In this 24-h cycling draft-legal event, performance in females remained unchanged while their age of peak cycling performance decreased and performance in males improved while their age of peak cycling performance remained unchanged. The annual fastest females and males were 37.3 ± 8.5 and 38.3 ± 5.4 years old, respectively. The sex difference for the fastest finishers was ~20%. It seems that women were not able to profit from drafting to improve their ultra-cycling performance.
authors.affiliation: Institute of General Practice and Health Services Research, University of Zurich, Zurich, Switzerland.
authors.forename: Lara
authors.initials: L
authors.lastname: Pozzi
authors.affiliation: Institute of General Practice and Health Services Research, University of Zurich, Zurich, Switzerland ; Gesundheitszentrum St. Gallen, St. Gallen, Switzerland.
authors.forename: Beat
authors.initials: B
authors.lastname: Knechtle
authors.affiliation: Gesundheitszentrum St. Gallen, St. Gallen, Switzerland.
authors.forename: Patrizia
authors.initials: P
authors.lastname: Knechtle
authors.affiliation: Institute of General Practice and Health Services Research, University of Zurich, Zurich, Switzerland.
authors.forename: Thomas
authors.initials: T
authors.lastname: Rosemann
authors.affiliation: INSERM U1093, University of Burgundy, Faculty of Sport Sciences, Dijon, France.
authors.forename: Romuald
authors.initials: R
authors.lastname: Lepers
authors.affiliation: Institute of General Practice and Health Services Research, University of Zurich, Zurich, Switzerland.
authors.forename: Christoph Alexander
authors.initials: CA
authors.lastname: Rüst
keywords: Cycling; Master athletes; Sex difference; Ultra-endurance