Int J Sports Med 2000; 21(2): 139-145
DOI: 10.1055/s-2000-11065
Nutrition
Georg Thieme Verlag Stuttgart ·New York

Effect of Exogenous Creatine Supplementation on Muscle PCr Metabolism

M. Francaux1 , R. Demeure2 , J.-F. Goudemant3 , J. R. Poortmans4
  • 1 Institut d'Education Physique et de Réadaptation, Université Catholique de Louvain, Louvain-la-Neuve, Belgium
  • 2 Unité de Résonance Magnétique Biomédicale, Université Catholique de Louvain, Bruxelles, Belgium
  • 3 Département de Chimie Organique, Université de Mons-Hainaut, Mons, Belgium
  • 4 Institut Supérieur d'Education Physique et de Kinésithérapie, Université Libre de Bruxelles, Bruxelles, Belgium
Further Information

Publication History

Publication Date:
31 December 2000 (online)

31P NMR was used to assess the influence of two weeks creatine supplementation (21 g · d-1) on resting muscle PCr concentration, on the rate of PCr repletion (Rdepl), and on the half-time of PCr repletion (t1/2). Body mass (BM) and volume of body water compartments were also estimated by impedance spectroscopy. Fourteen healthy male subjects (20.8 ± 1.9 y) participated in this double-blind study. PCr was measured using a surface coil placed under the calf muscle, at rest and during two exercise bout the duration of which was 1 min. They were interspaced by a recovery of 10 min. The exercises comprised of 50 plantar flexions-extensions against weights corresponding to 40 % and 70 % of maximal voluntary contraction (MVC), respectively. Creatine supplementation increased resting muscle PCr content by ∼20 % (P = 0.002). Rdepl was also increased by ∼15 % (P < 0.001) and ∼10 % (P = 0.026) during 40 % and 70 % MVC exercises, respectively. No change was observed in Rrepl and t1/2. BM and body water compartments were not influenced. These results indicate that during a standardized exercise more ATP is synthesized by the CK reaction when the pre-exercise level in PCr is higher, giving some support to the positive effects recorded on muscle performance.

References

Marc Francaux

Institut d'Education Physique et de Réadaptation

Place Pierre de Coubertin - 1

B-1348 Louvain-la-Neuve

Belgium

Phone: + 32 (10) 474457

Fax: + 32 (10) 472093

Email: marc.francaux@edph.ucl.ac.be