Effects of branched-chain amino acid supplement on creatine kinase levels after intermittent exercise

Abstract

Introduction: Exercise often leads to muscles damage. Previous study demonstrated that branched-chain amino acidsdrink helped reducing muscle fiber proteins degradation and attenuated muscle disruption damage. Therefore,this study aimed to investigate the effects of branched-chain amino acid supplement on creatine kinaselevels after intermittent exercise.

Methods: Participants in the experiment were 9 football players, aged 18-25 years old. There were 3 experimentalgroups. Each experimental group separated by at least one week. In each experimental group participantswere cycling at 65 percent alternate with 85 percent maximum oxygen consumption until they feltfatigued. Participants received by three different types of drinks, branched-chain amino acid, carbohydrateand placebo at 15 minutes before exercising and at 45 minutes after exercise. Blood samples were takenat the same time of measured rating of perceived soreness score.

Results: Creatine kinase levels were no significant different after exercise in between 3 groups. However, ratingof perceived soreness score in branched-chain amino acid group was significantly less than carbohydrateand placebo groups after exercise (p < 0.05). In addition, rating of perceived soreness score in carbohydrategroup was less than in the placebo group after exercise (p < 0.05). Levels of blood glucose in carbohydrategroup was higher than branched-chain amino acid and placebo groups after exercise at 15 and 75 minutes(p < 0.05). Time to fatigue, in branched-chain amino acid group and carbohydrate groups were significantlymore than in the placebo group (p < 0.05).

Discussion and Conclusion: Receiving the branched-chain amino acid supplement did not affect on creatine kinase levels, nevertheless it attenuated rating of perceived soreness score and improved the time to fatigue.

Key words: Branched-chain amino acid, Creatine kinase, Intermittent exercise.