title: Relationships and significance of lactate minimum, critical velocity, heart rate deflection and 3 000 m track-tests for running.
abstract: OBJECTIVE
  The running velocities associated to lactate minimum (V(lm)), heart rate deflection (V(HRd)), critical velocity (CV), 3.000 m (V(3000)) and 10 000 m performance (V10km) were compared. Additionally the ability of V(lm) and V(HRd) on identifying sustainable velocities was investigated.
  
  
  METHODS
  Twenty runners (28.5+/-5.9 y) performed 1) 3,000 m running test for V3000; 2) an all-out 500 m sprint followed by 6x800 m incremental bouts with blood lactate ([lac]) measurements for V(lm); 3) a continuous velocity-incremented test with heart rate measurements at each 200 m for V(HRd); 4) participants attempted to 30 min of endurance test both at V(lm)(ETV(lm)) and V(HRd)(ETV(HRd)). Additionally, the distance-time and velocity-1/time relationships produced CV by 2 (500 m and 3 000 m) or 3 predictive trials (500 m, 3,000 m and distance reached before exhaustion during ETV(HRd)), and a 10 km race was recorded for V10km.
  
  
  RESULTS
  The CV identified by different methods did not differ to each other. The results (m.min(-1)) revealed that V(lm) (281+/-14.8)<CV (292.1+/-17.5)=V10km (291.7+/-19.3)<V(HRd) (300.8+/-18.7)=V3000 (304+/-17.5) with high correlation among parameters (P<0.001). During ETVlm participants completed 30 min of running while on the ETV(HRd) they lasted only 12.5+/-8.2 min with increasing [lac].
  
  
  CONCLUSIONS
  We evidenced that CV and Vlm track-protocols are valid for running evaluation and performance prediction and the parameters studied have different significance. The V(lm) reflects the moderate-high intensity domain (below CV), can be sustained without [lac] accumulation and may be used for long-term exercise while the V(HRd)overestimates a running intensity that can be sustained for long-time. Additionally, V3000 and V(HRd) reflect the severe intensity domain (above CV).
authors.affiliation: Catholic University of Brasilia, Brasilia-DF, Brazil. hsimoes@pos.ucb.br
authors.forename: H G
authors.initials: HG
authors.lastname: Simões
authors.forename: B S
authors.initials: BS
authors.lastname: Denadai
authors.forename: V
authors.initials: V
authors.lastname: Baldissera
authors.forename: C S G
authors.initials: CS
authors.lastname: Campbell
authors.forename: D W
authors.initials: DW
authors.lastname: Hill
mesh_terms: D000328:Adult; D015308:Anaerobic Threshold / Q000502:physiology; D005080:Exercise Test; D017079:Exercise Tolerance / Q000502:physiology; D005221:Fatigue; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D019344:Lactic Acid / Q000097:blood*; D008297:Male; D010101:Oxygen Consumption / Q000502:physiology*; D010807:Physical Endurance / Q000502:physiology*; D011446:Prospective Studies; D012420:Running / Q000502:physiology*; D014142:Track and Field / Q000502:physiology*
chemical_list: D019344:Lactic Acid