Short-term Effects of Whey, Creatine, and L-carnitine Supplementation on Muscle Hypertrophy Marker Candidates in Young Males: A Randomized Placebo-controlled Pilot Study

Abstract

Previous research showed that resistance exercise could induce muscle development, noticeably from the increased level of several markers from blood samples. However, no study had been performed to explore the effect of combination of resistance exercise and proper nutrition supply on those markers. The aim of this study to investigate the effect of whey protein, creatine, and L-carnitine; on potential molecular markers of muscle hypertrophy (arg1 and mmp9) from blood samples. Twelve healthy male participants were randomly categorized into supplement (SUPP) or placebo (PLAC) treatment, and performed resistance training three times in a one-week period. Blood sampling was carried out before (day one) and 2 hours after the exercise (day one, day three and day five). The level of mmp9 gene expression was increased along with the progress of the resistance training program. Moreover, participants who received supplementation (SUPP) showed a higher level of mmp9 gene expression compared to resistance training only (PLAC). A significant difference was observed between two treatments in the first day, 2 hours after the resistance training session (p = .04); and between SUPP group on the fifth day, 2 hours after the resistance training; compared to the first day, before the resistance training session (p = .02). The effect was not observed on arg1 gene. A combination of resistance training with supplementation; was considered to enhance the muscle hypertrophy process, compared to resistance training only. The results also suggested that mmp9 could act as a blood-derived molecular marker of muscle hypertrophy.