Blood Lactate and Oxygen Debt After Exhaustive Work at Different Oxygen Tensions.

Abstract

SummaryOn the International High Expedition to Chile Edwards (1936) found that the maximum lactate concentration after exhaustive work was much lower than at sea level. In the present experiments with acute changes of the oxygen tension in the inspired air the following results were found. At a decreased oxygen tension the capacity for work was lowered, but the maximum lactate concentration was, practically, the same or —in one type of work—higher than in normal air. Also the oxygen debt was practically the same as in normal air. In pure oxygen the capacity for work was increased but the maximal blood lactate concentration was practically the same as in normal air. A lowering of the alkaline reserve by ingestion of NH4C1 corresponding to the decrease found at altitudes from 3.7 to 6.0 km had no effect on the capacity for work or on the maximum blood lactate concentration and oxygen debt after exhaustive work. According to these results it seems doubtful that the failing ability to accumulate large amounts of lactic acid at high altitudes is the effect of a useful acclimatization, but that it is due rather to a progressive weakening of the subjects making them less able to perform anaerobic work.