Creatine supplementation???Part II: in vivo magnetic resonance spectroscopy

Abstract

KREIS, R., M. KAMBER, M. KOSTER, J. FELBLINGER, J. SLOTBOOM, H. HOPPELER, and C. BOESCH. Creatine supplementation—Part II: in vivo magnetic resonance spectroscopy. Med. Sci. Sports Exerc., Vol. 31, No. 12, pp. 1770–1777, 1999. Our purpose was to study effects of creatine (Cr) supplementation on muscle metabolites noninvasively by means of magnetic resonance spectroscopy (MRS) before and after supplementation with Cr or placebo. 1H-MRS was used in a comprehensive, double-blind, cross-over study in 10 volunteers to measure Cr in m. tibialis anterior and m. rectus femoris at rest. PCr/ATP was observed in m. quadriceps femoris by 31P-MRS at rest and after exercise. A significant increase in total Cr was observed with Cr intake in m. tibialis anterior (+9.6 ± 1.7%, P = 0.001) and in m. rectus femoris (+18.0 ± 1.8%, P P Noninvasive observation of Cr and PCr after Cr supplementation shows an increase in a muscle specific manner. Higher preexercise levels of PCr/ATP at rest compensate for significantly slower recovery rates of PCr/ATP after Cr supplementation.