Abstract |
We hypothesised that dichloroacetate (DCA) would reduce blood lactate accumulation, pulmonary carbon dioxide output (.V(CO2)) and ventilation (.V(E)) at sub-maximal work rates, and improve exercise tolerance during incremental exercise in healthy humans. Nine males (mean+/-SD, age 27+/-4 years) completed, in random order, two ramp incremental cycle ergometer tests to the limit of tolerance following the intravenous infusion of DCA (75 mg/kg body mass in 80 ml saline) or an equivalent volume of saline (as placebo). Relative to control, blood [ lactate] was significantly reduced by DCA immediately before exercise (CON: 0.7+/-0.2 vs. DCA: 0.5+/-0.2mM; P<0.05) and throughout exercise until 630s (P<0.05). Blood [HCO(3)(-)] was significantly higher in the DCA condition from 360s until 720s of exercise (P<0.05). .V(CO2) and .V(E) were both lower throughout exercise in the DCA condition, with the differences reaching significance at 90 and 180s for .V(CO2) (P<0.05) and at 90, 180, 450, 540, 630, and 810s for .V(E) (P<0.05). Exercise tolerance was not significantly altered (CON: 1029+/-109 vs. DCA: 1045+/-101s). Infusion of DCA resulted in reductions in blood [ lactate], .V(CO2) and .V(E) during sub-maximal incremental exercise, consistent with the existence of a link between the bicarbonate buffering of metabolic acidosis and increased CO(2) output. However, the reduced blood lactate accumulation during sub-maximal exercise with DCA did not enhance exercise tolerance.
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Authors | Daryl P Wilkerson, Iain T Campbell, Jamie R Blackwell, Nicolas J Berger, Andrew M Jones |
Journal | Respiratory physiology & neurobiology
(Respir Physiol Neurobiol)
Vol. 168
Issue 3
Pg. 224-9
(Sep 30 2009)
ISSN: 1878-1519 [Electronic] Netherlands |
PMID | 19615473
(Publication Type: Clinical Trial, Journal Article)
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Chemical References |
- Bicarbonates
- Lactic Acid
- Dichloroacetic Acid
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Topics |
- Adult
- Bicarbonates
(blood)
- Dichloroacetic Acid
(pharmacology)
- Energy Metabolism
- Exercise
(physiology)
- Exercise Tolerance
- Heart Rate
(drug effects)
- Humans
- Lactic Acid
(blood)
- Male
- Oxygen Consumption
(drug effects)
- Physical Exertion
(drug effects)
- Pulmonary Gas Exchange
(drug effects)
- Pulmonary Ventilation
(drug effects)
- Young Adult
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