Influence of short and long term creatine supplementation on enzymatic markers of muscle damage in sedentaries and exercised rats

Abstract

The aim of this study was to investigate the effects of the short-term (5 g.kg-1 to 1 week) and long-term (1 g.kg-1 to 4-8 weeks) creatine supplementation (Cr) on the Creatine Kinase (CK), Lactate Dehydrogenaze (LDH) and Aspartate Aminotransferase (AST) plasmatic concentrations of sedentary and exercised (swimming to 80% of the tolerated maximum load) rats. Seventy two Wistar males rats (250 ± 10 g) were equally divided in four groups: sedentary rats without supplementation (CON; n = 18); exercised rats without supplementation (NAT; n = 18); sedentary rats with supplementation (CRE; n = 18); exercised rats with supplementation (CRE+NAT; n = 18). At the end of the first, fourth and eighth weeks six animals of each group were sacrificed. The results demonstrated: 1) improvement of CK, LDH and AST in NAT-1 and CRE+NAT-1 groups vs. CON-1 and CRE-1 groups after the first experimental week; 2) higher values of CK and LDH only NAT-4 group after four experimental weeks; and 3) only AST from CRE-8 group differed from other groups at the end of the eighth experimental week. These findings suggest that the Cr supplementation: 1) does not affect the muscle damage on swimming exercised rats after one week of high intensity training; 2) could be able to reduce the muscle damage after 4 weeks of training; and 3) after eight weeks of Cr supplementation, the muscle damage seems to be attenuated by the exercise, nullifying the effects of Cr.