EFFECT OF CREATINE ON AEROBIC AND ANAEROBIC METABOLISM IN SKELETAL-MUSCLE IN SWIMMERS

Objective-To examine the effect of a relatively low dose of creatine o n skeletal muscle metabolism and oxygen supply in a group of training athletes. Methods-P-31 magnetic resonance and near-infrared spectrosco py were used to study calf muscle metabolism in a group of 10 female m embers of a university swimming team. Studies were performed before an d after a six week period of training during which they took either 2 g creatine daily or placebo. metabolism and creatine/choline were stud ied in resting muscle, during plantar flexion exercise (10-15 min), an d during recovery from exercise. Results-There was no effect of creati ne on metabolite ratios at rest or on metabolism during exercise and r ecovery from exercise. Muscle oxygen supply and exercise performance w ere not improved by creatine if compared to placebo treated subjects. Conclusions-Oral creatine supplementation at 2 g daily has no effect o n muscle creatine concentration, muscle oxygen supply or muscle aerobi c or anaerobic metabolism during endurance exercise.