title: Steady-state acid-base response at exercise levels close to maximum lactate steady state.
abstract: OBJECTIVE
  To study acid-base status during a constant-load treadmill test at exercise levels close to the maximum lactate steady-state.
  
  
  METHODS
  Two tests were performed: one maximal and one steady-state at a load corresponding to the mean of the two ventilatory thresholds observed in the first test.
  
  
  METHODS
  University Sports Science Laboratory.
  
  
  METHODS
  Twenty-three male Sports Science students, aged 26.7 (+/- 4.9 SD) years, 176.1 (+/- 6.3) cm in height, and weighing 72.8 (+/- 6.7) kg.
  
  
  METHODS
  Capillary blood gases, metabolites, electrolytes.
  
  
  RESULTS
  Acid-base status variables declined significantly during the maximal test. Lactate concentrations were above the values observed at onset of blood lactate accumulation. All the blood variables did not vary significantly at the various experimental times, except pH values and PCO2 values. Bicarbonate concentration remained constant. Plasma potassium, chlorine and sodium concentration did not increase.
  
  
  CONCLUSIONS
  During a steady-state test at a load corresponding to approximately 80% of VO2max, the acid-base status in capillary blood remained constant even though the lactate concentration was over 4 mmol/L. However, despite the maintenance of a constant acid-base status, other physiological variables did not behave in the same fashion.
authors.affiliation: Facultad de Ciencias de la Actividad Fisica y el Deporte- INEF, Universidad Politécnica de Madrid, Spain. pedroj.benito@upm.es
authors.forename: Pedro J B
authors.initials: PJ
authors.lastname: Peinado
authors.forename: Valter
authors.initials: V
authors.lastname: Di Salvo
authors.forename: Fabio
authors.initials: F
authors.lastname: Pigozzi
authors.forename: Ana I P
authors.initials: AI
authors.lastname: Bermúdez
authors.forename: Ana B
authors.initials: AB
authors.lastname: Peinado Lozano
authors.forename: Francisco J
authors.initials: FJ
authors.lastname: Calderón Montero
authors.forename: Nicola
authors.initials: N
authors.lastname: Maffulli
mesh_terms: D000136:Acid-Base Equilibrium / Q000502:physiology*; D000328:Adult; D015308:Anaerobic Threshold / Q000502:physiology; D001774:Blood Chemical Analysis; D001784:Blood Gas Analysis; D015444:Exercise / Q000502:physiology*; D006801:Humans; D019344:Lactic Acid / Q000097:blood* / Q000378:metabolism; D008297:Male
chemical_list: D019344:Lactic Acid