title: Age and sex differences pertaining to modes of locomotion in triathlon.
abstract: OBJECTIVE
  The magnitude of change in sex differences across age groups in triathlon performance for the Ironman distance has been established. However, the influence of age on sex differences at shorter-distance triathlons is yet to be determined. The aim of this study was to compare sex differences across age groups for the different modes of locomotion among varying triathlon distances (Sprint, Olympic, and Ironman 70.3) in amateur triathletes from the 2009-2011 triathlon World Championship.
  
  
  METHODS
  Data for the top 10 male and female amateur triathletes for the age groups between 18 and 64 yr were collected from the 2009-2011 World Championships for Sprint, Olympic, and Ironman 70.3 triathlons. Sex differences across age groups were compared using time performances for swimming, cycling, running, transition time, overall race time, and estimated power output.
  
  
  RESULTS
  Total time differences between sexes were largest in 55-59 yr age groups for Sprint (18.7%, P < 0.05) and in 60-64 yr age groups for Olympic and Ironman 70.3 (14.8% and 21.7%, P < 0.05). Mean sex difference in performance time was smallest for cycling in Sprint (11.8% ± 0.41%) and in Ironman 70.3 (11.2% ± 0.41%), whereas running showed the smallest sex difference in Olympic (7.5% ± 0.33%, P < 0.05). Mean sex differences in estimated power output were significantly greater for swimming in Sprint (41.0% ± 1.47%), Olympic (39.8% ± 1.24%), and Ironman 70.3 (37.%5 ± 1.67%, P < 0.05).
  
  
  CONCLUSIONS
  Sex differences for total performance time were greatest in the youngest age groups and older age groups for Sprint, Olympic, and Ironman 70.3 distances. Sex differences varied among the modes of locomotion for the three distances of triathlons; however, for short- to mid-distance triathlons, both performance time and estimated power output seem to indicate that the largest sex differences exist for swimming.
authors.affiliation: Department of Nutrition, Hospitality, and Retailing, Texas Tech University, Lubbock, TX 79409, USA.
authors.forename: Jada L
authors.initials: JL
authors.lastname: Stevenson
authors.forename: Huaxin
authors.initials: H
authors.lastname: Song
authors.forename: Jamie A
authors.initials: JA
authors.lastname: Cooper
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D001642:Bicycling / Q000293:injuries*; D005260:Female; D006801:Humans; D008124:Locomotion / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D010101:Oxygen Consumption; D012420:Running / Q000502:physiology*; D012737:Sex Factors; D013550:Swimming / Q000502:physiology*; D055815:Young Adult