Lactate metabolism: bioenergetics and muscle fatigue review

Resumen

The purpose of this study was to present the main events regarding the muscle lactate metabolism to aid the understanding about utilization of the blood lactate concentrations (BLC) on the estimative of lactic anaerobic metabolism and its likely relationship to the acute muscle fatigue. Traditionally, the increase of BLC was associated to the insufficient mitochondrial O2 supply. However, recent studies showed that increase of BLC can be due the action of another agent such as epinephrine and inorganic phosphate. In the same way, the relationship between BLC and acute muscle fatigue has been supported by increase in cellular acidosis. Nevertheless, recent studies have shown that cellular acidosis can restore the force in isolated and electrically stimulated muscle fibers. These findings suggest that utilization of the BLC on the estimative of lactic anaerobic metabolism should be used with caution and the relationship between BLC and acute muscle fatigue can only be a casual phenomenon.