title: Influence of different performance levels on pacing strategy during the Women's World Championship marathon race.
abstract: OBJECTIVE
  To analyze pacing strategies displayed by athletes achieving differing levels of performance during an elite-level marathon race.
  
  
  METHODS
  Competitors in the 2009 IAAF Women's Marathon Championship were split into groups 1, 2, 3, and 4 comprising the first, second, third, and fourth 25% of finishers, respectively. Final, intermediate, and personal-best (PB) times of finishers were converted to mean speeds, and relative speed (% of PB speed) was calculated for intermediate segments.
  
  
  RESULTS
  Mean PB speed decreased from groups 1 to 4, and speeds maintained in the race were 98.5% ± 1.8%, 97.4% ± 3.2%, 95.0% ± 3.1%, and 92.4% ± 4.4% of PB speed for groups 1-4 respectively. Group 1 was fastest in all segments, and differences in speed between groups increased throughout the race. Group 1 ran at lower relative speeds than other groups for the first two 5-km segments but higher relative speeds after 35 km. Significant differences (P < .01) in the percentage of PB speed maintained were observed between groups 1 and 4 and groups 2 and 4 in all segments after 20 km and groups 3 and 4 from 20 to 25 km and 30 to 35 km.
  
  
  CONCLUSIONS
  Group 1 athletes achieved better finishing times relative to their PB than athletes in other groups, who selected unsustainable initial speeds resulting in subsequent significant losses of speed. It is suggested that psychological factors specific to a major competitive event influenced decision making by athletes, and poor decisions resulted in final performances inferior to those expected based on PB times.
authors.affiliation: Institute of Sport and Exercise Science, University of Worcester, Worcester, United Kingdom.
authors.forename: Andrew
authors.initials: A
authors.lastname: Renfree
authors.forename: Alan
authors.initials: A
authors.lastname: St Clair Gibson
mesh_terms: D000328:Adult; D056352:Athletes / Q000523:psychology; D054874:Athletic Performance / Q000502:physiology* / Q000523:psychology*; D003163:Competitive Behavior / Q000502:physiology; D003657:Decision Making / Q000502:physiology; D005260:Female; D006801:Humans; D010807:Physical Endurance / Q000502:physiology*; D012420:Running / Q000502:physiology* / Q000523:psychology*; D013997:Time Factors