Muscle metabolism of professional athletes using 31P-spectroscopy

The aim of the study was to examine muscle metabolism in athletes by 31P-spectroscopy (MRS) and to evaluate to what degree the respective resonance spectrum correlates with the kind of muscle exercise. Twelve runners and 12 young ice skaters were studied by 31P-spectroscopy of the gastrocnemic medialis muscle and the vastus medialis muscle using a surface coil at 1.5 T. Sprinters displayed a higher phosphocreatinine/inorganic phosphate (PCr/Pi) and PCr/beta-ATP ratios than marathon runners. The respective parameters for middle distance runners were in between. Ice skaters could prospectively be divided into sprint- and long-distance runners by our results which correlated with the athletes' training performance. 31P-spectroscopy can evaluate the distribution of muscle fiber types. Thus, the athlete's potential for sprint- or long-distance running can be determined. Additional studies will have to demonstrate to what extent training may change muscle fiber distribution.