Effect of chronic alcoholism on human muscle glycogen and glucose metabolism.

To determine the effect of alcohol on carbohydrate metabolism, 48 human muscle biopsies from chronic alcoholics were studied. The level of glycogen and the activities of the enzymes catalyzing glycogen and glucose metabolism were analyzed. Chronic alcohol intake produced an increase in glycogen concentration and a decrease in pyruvate kinase activity before the first signs of myopathy appeared. When myopathy was present, glycogen decreased. These changes may contribute to the decline in skeletal muscle performance in these patients.