EFFECT OF ENDURANCE TRAINING ON AMMONIA AND AMINO-ACID-METABOLISM IN HUMANS

Few studies examine ammonia and amino acid metabolism in response to e ndurance training. Trained humans generally experience less increase i n plasma ammonia during either prolonged or intense exercise. This is probably a reflection of reduced ammonia production and release from t he active muscle; it could be a reflection of decreased AMP deaminase activity, decreased glutamate dehydrogenase activity, and/or increased alanine and glutamine formation. Little is known regarding the associ ated enzyme systems in humans, but in experiments with animal models, aerobic training decreases AMP deaminase and increases the enzymes of amino acid transamination and oxidation.