Improved energy kinetics following high protein diet in McArdle's syndrome. A 31P magnetic resonance spectroscopy study.

A patient with McArdle's syndrome was examined using bicycle ergometry and 31P NMR spectroscopy during exercise. The patients working capacity was approximately half the expected capacity of controls. Muscle energy kinetics improved significantly during intravenous glucose infusion and after 6 weeks of high protein diet. During intravenous infusion of amino acids, no changes in working capacity could be detected. No decrease was seen in intracellular muscle pH during aerobic exercise. A significant decrease in muscle pH during aerobic exercise was detected in all controls.