Physical exercise after induced alkalosis (bicarbonate or tris-buffer).

The influence of bicarbonate and Tris-buffer infusions on the performance capacity for maximal, brief exercise (400 m run) was studied using 10 normal males in their twenties. Run time, maximal lactate concentration and heart rate remained unchanged after the buffer infusions. As a result of the induced elevated buffering capacity, the average pH after exercise was about 0.1 unit higher. Corresponding values for base excess and standard bicarbonate were found. The arterial pCO2 was higher after infusion as a result of the active respiratory compensation. Since the reduction in the work-related metabolic acidosis by the buffering substances caused no improvement in performance, the importance of pH as the performance-limiting factor must be questioned because the investigation gave no evidence for alterations of intracellular pH.