title: Variation in performance times of elite flat-water canoeists from race to race.
abstract: OBJECTIVE
  To estimate variability in performance time and smallest worthwhile changes for elite flat-water canoeists competing in 200-, 500- or 1000-m events at international regattas.
  
  
  METHODS
  The data came from A and B finals held at 7 to 13 regattas in 2003 to 2007. A linear mixed-model analysis of log-transformed official race times provided estimates of variability as coefficients of variation and included terms to account for changes in performance between years, venues, and A and B finals.
  
  
  RESULTS
  For men, the within-athlete variation in A finals was similar in canoeing and kayaking events, with the 200-m men's events demonstrating probably less variability than the longer events (by an overall factor of 0.75, x// 1.33) that may reflect differences in pacing strategies. In contrast, the within-athlete variation for women kayakers in A finals of the 500-m event was only half that of the other distances (ratio 0.54, x// 1.29), possibly because of differences in competitive experience or depth of competition. Predictability of performance in A finals was moderate to very high (interclass correlations 0.40 to 0.89). Within-athlete variation in the B finals was generally greater than in the A finals for the three distances for men, but there was no clear pattern for women.
  
  
  CONCLUSIONS
  The smallest worthwhile changes in performance time (0.3 x within-athlete variability) in canoeing and kayaking are approx. 0.3% to 0.6%. Effects of 1% to 2% in power output would be required to achieve such changes in this generally highly predictable sport.
authors.affiliation: Department of Physiology, Australian Institute of Sport, Bruce, ACT, Australia.
authors.forename: Darrell L
authors.initials: DL
authors.lastname: Bonetti
authors.forename: Will G
authors.initials: WG
authors.lastname: Hopkins
mesh_terms: D054874:Athletic Performance / Q000502:physiology*; D005260:Female; D006801:Humans; D016014:Linear Models; D008297:Male; D012737:Sex Factors; D013177:Sports / Q000502:physiology*; D013997:Time Factors