title: Blood lactate clearance after maximal exercise depends on active recovery intensity.
abstract: OBJECTIVE
  High-intensity exercise is time-limited by onset of fatigue, marked by accumulation of blood lactate. This is accentuated at maximal, all-out exercise that rapidly accumulates high blood lactate. The optimal active recovery intensity for clearing lactate after such maximal, all-out exercise remains unknown. Thus, we studied the intensity-dependence of lactate clearance during active recovery after maximal exercise.
  
  
  METHODS
  We constructed a standardized maximal, all-out treadmill exercise protocol that predictably lead to voluntary exhaustion and blood lactate concentration>10 mM. Next, subjects ran series of all-out bouts that increased blood lactate concentration to 11.5±0.2 mM, followed by recovery exercises ranging 0% (passive)-100% of the lactate threshold.
  
  
  RESULTS
  Repeated measurements showed faster lactate clearance during active versus passive recovery (P<0.01), and that active recovery at 60-100% of lactate threshold was more efficient for lactate clearance than lower intensity recovery (P<0.05). Active recovery at 80% of lactate threshold had the highest rate of and shortest time constant for lactate clearance (P<0.05), whereas the response during the other intensities was graded (100%=60%>40%>passive recovery, P<0.05).
  
  
  CONCLUSIONS
  Active recovery after maximal all-out exercise clears accumulated blood lactate faster than passive recovery in an intensity-dependent manner, with maximum clearance occurring at active recovery of 80% of lactate threshold.
authors.affiliation: Institute of Cardiovascular and Medical Sciences - Ole.Kemi@glasgow.ac.uk.
authors.forename: J
authors.initials: J
authors.lastname: Devlin
authors.forename: B
authors.initials: B
authors.lastname: Paton
authors.forename: L
authors.initials: L
authors.lastname: Poole
authors.forename: W
authors.initials: W
authors.lastname: Sun
authors.forename: C
authors.initials: C
authors.lastname: Ferguson
authors.forename: J
authors.initials: J
authors.lastname: Wilson
authors.forename: O J
authors.initials: OJ
authors.lastname: Kemi
mesh_terms: D015444:Exercise / Q000502:physiology*; D005080:Exercise Test; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D007773:Lactates / Q000097:blood*; D008297:Male; D010101:Oxygen Consumption / Q000502:physiology; D020127:Recovery of Function / Q000502:physiology*; D055815:Young Adult
chemical_list: D007773:Lactates