OXYGEN DRIFT NOT ASSOCIATED WITH ACID-BASE BALANCE
Heck, K. L., Potteiger, J. A., Nau, K. L., & Schroeder, J. M. (1996). Induced alkalosis does not attenuate the oxygen drift during constant-load exercise. Medicine and Science in Exercise and Sports, 28(5), Supplement abstract 1082.
During prolonged high-intensity exercise there is an upward drift in oxygen consumption. In constant-load work, it has been hypothesized that the drift is due to a decrease in blood and muscle pH.
This investigation induced an increase in pH by having Ss ingest sodium bicarbonate (0.3 gm/kgBW). A 30-minute exercise response under a placebo and the induced-alkalosis condition were compared.
Acid-base measures were significantly elevated during the alkalosis condition but the oxygen drift phenomenon still occurred.
Implication. Changes in blood and muscle acidity during prolonged, constant, hard exercise do not cause the oxygen drift phenomenon to change or be reduced.
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