title: Post-analysis methods for lactate threshold depend on training intensity and aerobic capacity in runners. An experimental laboratory study.
abstract: OBJECTIVE
  This study aimed to evaluate different mathematical post-analysis methods of determining lactate threshold in highly and lowly trained endurance runners.
  
  
  METHODS
  Experimental laboratory study, in a tertiary-level public university hospital.
  
  
  METHODS
  Twenty-seven male endurance runners were divided into two training load groups: lowly trained (frequency < 4 times per week, < 6 consecutive months, training velocity ≥ 5.0 min/km) and highly trained (frequency ≥ 4 times per week, ≥ 6 consecutive months, training velocity < 5.0 min/km). The subjects performed an incremental treadmill protocol, with 1 km/h increases at each subsequent 4-minute stage. -Fingerprint -blood-lactate analysis was performed at the end of each stage. The lactate threshold (i.e. the running velocity at which blood lactate levels began to exponentially increase) was measured using three different methods: increase in blood lactate of 1 mmol/l at stages (DT1), absolute 4 mmol/l blood lactate concentration (4 mmol), and the semi-log method (semi-log). ANOVA was used to compare different lactate threshold methods and training groups.
  
  
  RESULTS
  Highly trained athletes showed significantly greater lactate thresholds than lowly trained runners, regardless of the calculation method used. When all the subject data were combined, DT1 and semi-log were not different, while 4 mmol was significantly lower than the other two methods. These same trends were observed when comparing lactate threshold methods in the lowly trained group. However, 4 mmol was only significantly lower than DT1 in the highly trained group.
  
  
  CONCLUSIONS
  The 4 mmol protocol did not show lactate threshold measurements comparable with DT1 and semi-log protocols among lowly trained athletes.
authors.affiliation: Sports Medicine Group, FIFA Medical Centre of Excellence, Faculdade de Medicina da Universidade de São Paulo (FMUSP), São Paulo, Brazil.|Instituto de Ortopedia e Traumatologia (IOT), Hospital das Clínicas (HC) da Universidade de São Paulo, São Paulo, Brazil.
authors.forename: Tiago Lazzaretti
authors.initials: TL
authors.lastname: Fernandes
authors.affiliation: Faculdade de Medicina da Universidade de São Paulo (FMUSP), São Paulo, Brazil.
authors.forename: Rômulo Dos Santos Sobreira
authors.initials: Rdos S
authors.lastname: Nunes
authors.affiliation: Heart Institute, Faculdade de Medicina da Universidade de São Paulo (FMUSP), São Paulo, Brazil.
authors.forename: Cesar Cavinato Cal
authors.initials: CC
authors.lastname: Abad
authors.affiliation: Sports Medicine Group, Faculdade de Medicina da Universidade de São Paulo (FMUSP), São Paulo, Brazil.|Instituto de Ortopedia e Traumatologia (IOT), Hospital das Clínicas (HC) da Universidade de São Paulo, São Paulo, Brazil.
authors.forename: Andrea Clemente Baptista
authors.initials: AC
authors.lastname: Silva
authors.affiliation: Sports Medicine Group, Faculdade de Medicina da Universidade de São Paulo (FMUSP), São Paulo, Brazil.|Instituto de Ortopedia e Traumatologia (IOT), Hospital das Clínicas (HC) da Universidade de São Paulo, São Paulo, Brazil.
authors.forename: Larissa Silva
authors.initials: LS
authors.lastname: Souza
authors.affiliation: Sports Medicine Group, FIFA Medical Centre of Excellence, Faculdade de Medicina da Universidade de São Paulo (FMUSP), São Paulo, Brazil.
authors.forename: Paulo Roberto Santos
authors.initials: PR
authors.lastname: Silva
authors.affiliation: Department of Mechanical Engineering, Centro Universitário da FEI, São Bernando do Campo, Brazil.
authors.forename: Cyro
authors.initials: C
authors.lastname: Albuquerque
authors.affiliation: Faculdade de Medicina da Universidade de São Paulo (FMUSP), São Paulo, Brazil.
authors.forename: Maria Cláudia
authors.initials: MC
authors.lastname: Irigoyen
authors.affiliation: Sports Medicine Group, FIFA Medical Centre of Excellence, Faculdade de Medicina da Universidade de São Paulo (FMUSP), São Paulo, Brazil.
authors.forename: Arnaldo José
authors.initials: AJ
authors.lastname: Hernandez
mesh_terms: D000328:Adult; D015308:Anaerobic Threshold / Q000502:physiology*; D000704:Analysis of Variance; D056352:Athletes; D005080:Exercise Test / Q000379:methods*; D006801:Humans; D019344:Lactic Acid / Q000097:blood*; D008297:Male; D008875:Middle Aged; D010807:Physical Endurance / Q000502:physiology*; D012016:Reference Values; D015203:Reproducibility of Results; D012420:Running / Q000502:physiology*; D013997:Time Factors; D055815:Young Adult
chemical_list: D019344:Lactic Acid