title: Scalar-linear increases in perceived exertion are dissociated from residual physiological responses during sprint-distance triathlon.
abstract: OBJECTIVE
  This study examined how residual fatigue affects the relationship between ratings of perceived exertion (RPE), physiological responses, and pacing during triathlon performance.
  
  
  METHODS
  Eight male triathletes completed a sprint-distance triathlon (750m swim, 20kmcycle and 5km run) and isolated 5km run on separate days. RPE, core temperature (Tcore), heart rate and blood lactate concentration [BLa(-)] were recorded during both, in addition to performance time and speed.
  
  
  RESULTS
  Triathlon run time (1248±121s) was significantly slower than the isolated run (1167±90s) (p<0.01). Significant differences were observed at the start of the two conditions for all physiological measures (Heart rate 162±4 vs 154±5 beatsmin(-1); Tcore 38.3±0.8 vs 36.7±0.6C; [BLa(-)] 9.1±2.8 vs 2.1±0.4mmolL(-1), for triathlon and isolated run, respectively, p<0.05). No significant differences were observed for initial RPE (p=0.083), rate of RPE increase (p=0.412), or final RPE (p=0.329) between run trials.
  
  
  CONCLUSIONS
  The maintenance of a scalar-linear increase in RPE by the brain remains the primary mechanism for pace regulation during both single and multi-modal endurance performance, with physiological responses being only indirectly related to this process. The apparent absence of any RPE 'resetting' between disciplines suggests that during shorter distance multi-sport performances (60-90 min) a cognitive pacing strategy for the entire event is employed. However, as subtle alterations in RPE development between disciplines were observed the existence of discipline-specific RPE 'templates' should not be discounted.
authors.affiliation: School of Sport and Exercise Science, University of Lincoln, Lincoln, LN6 7TS, United Kingdom. dtaylor@lincoln.ac.uk
authors.forename: Daniel
authors.initials: D
authors.lastname: Taylor
authors.forename: Mark F
authors.initials: MF
authors.lastname: Smith
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D054874:Athletic Performance / Q000502:physiology; D001642:Bicycling / Q000502:physiology; D001831:Body Temperature / Q000502:physiology; D001835:Body Weight / Q000502:physiology; D003627:Data Interpretation, Statistical; D006801:Humans; D008297:Male; D018763:Muscle Fatigue / Q000502:physiology; D005082:Physical Exertion / Q000502:physiology*; D012420:Running / Q000502:physiology*; D012649:Self Concept; D013550:Swimming / Q000502:physiology
keywords: Fatigue; Pacing; Perceived exertion; Running; Teleoanticipation; Triathlon