title: RPE association with lactate and heart rate during high-intensity interval cycling.
abstract: OBJECTIVE
  Physiological and perceptual measures during interval exercise are not well understood. The current study therefore examined the correspondence between RPE, HR, and blood lactate concentration ([La]) during interval cycling.
  
  
  METHODS
  VO2peak and the 4.0 mmol x L(-1) lactate threshold were determined. In session 2, subjects (N = 12) warmed up (10 min, 0 W) and completed five 2-min intervals (INT) at >4 mmol x L(-1) workload, each separated by 3 min of recovery (REC) (60 rpm, 0 W). HR, RPE, and [La] were recorded at 10 min, at the conclusion of each INT, and each REC and 5- and 10-min recovery.
  
  
  RESULTS
  Repeated-measures ANOVA showed [La], HR, and RPE increased significantly across time (INT and REC). At each time point, repeated-measures ANOVA was used to compare standardized data (alpha = 0.05). RPE (at INT) intensified concurrently with HR and [La] at INT. Correlations were significant for INT (P < or = 0.05) (HR-RPE: r = 0.63, [La]-RPE: r = 0.43). Similarly, RPE and HR for REC systematically increased with [La]. Correlations for REC were also significant (HR-RPE: r = 0.44, [La]-RPE: r = 0.34). Correlations were also significant for INT and REC combined (HR-RPE: r = 0.70, [La]-RPE: r = 0.22).
  
  
  CONCLUSIONS
  INT and REC independently showed moderate correspondence for RPE-[La] and RPE-HR. However, tighter overall coupling of HR with RPE (vs [La] with RPE) and a dissociation between RPE-[La] suggest RPE during intervals of intense cycling were more sensitive to acute metabolic demand (evidenced by HR) versus [La].
authors.affiliation: Department of Kinesiology, University of Alabama, Tuscaloosa, AL 35487, USA. mgreen@bamaed.ua.edu
authors.forename: James M
authors.initials: JM
authors.lastname: Green
authors.forename: John R
authors.initials: JR
authors.lastname: McLester
authors.forename: Thad R
authors.initials: TR
authors.lastname: Crews
authors.forename: Phillip J
authors.initials: PJ
authors.lastname: Wickwire
authors.forename: Robert C
authors.initials: RC
authors.lastname: Pritchett
authors.forename: Richard G
authors.initials: RG
authors.lastname: Lomax
mesh_terms: D000328:Adult; D001642:Bicycling / Q000502:physiology*; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D019344:Lactic Acid / Q000032:analysis*; D008297:Male; D019370:Observation; D010101:Oxygen Consumption; D010807:Physical Endurance / Q000502:physiology; D005082:Physical Exertion / Q000502:physiology*; D013647:Task Performance and Analysis; D014481:United States
chemical_list: D019344:Lactic Acid