ABSTRACT
As early as 1807, Berzelius speculated about the relation between lactic acid production and the extent of exercise (Lehman, 1850). Since then, the interaction between changes in acid-base balance and the mechanical output of working muscles has been widely explored. Exercise studies in humans have established a strong relation between increased blood lactate and a decline in the capacity to do exhaustive work (Bang, 1936; Asmussen et al., 1948; Karlsson et al ., 1975). Moreover, investigations testing the effects of pharmacologically induced acidosis on human muscular performance have demonstrated a negative effect on endurance (Dennig et al., 1931; Jones et al., 1977). Finally, experiments during which isolated muscle fibers were exposed to an acidotic environment have revealed decreased tension development, suggesting that the site of action for acidosis is on the muscle itself (Fabiato and Fabiato, 1978). In contrast, alkalosis temporarily augments contractility as well as endurance of striated muscle (Creese, 1950; Jones et al., 1977).
