Supplementing With Which Form of Creatine (Hydrochloride or Monohydrate) Alongside Resistance Training Can Have More Impacts on Anabolic/Catabolic Hormones, Strength and Body Composition?

The purpose of this study was to determine the effects of resistance training (RT) alongside creatine-hydrochloride (Cr-HCl) or creatine monohydrate (CrM) supplementation on anabolic/catabolic hormones, strength, and body composition. Forty participants with an age range of 18-25 years were randomly divided into four groups (n=10): RT+Cr-HCl (0.03 g.kg-1 of body mass), RT+CrM-loading phase (CrM-LP) (0.3 g.kg-1 of body mass for five days (loading) and 0.03 g.kg-1 body mass for 51 days (maintenance)), RT+CrM-without loading phase (CrM-WLP) (0.03 g.kg-1 body mass), and RT+placebo (PL). The participants consumed supplements and performed RT with an intensity of 70-85 % 1RM for eight weeks. Before and after the training and supplementation period, strength (1RM), body composition (percent body fat (PBF), skeletal muscle mass (SMM), muscular cross-sectional area (MCSA)) and serum levels of testosterone, growth hormone (GH), insulin-like growth factor-1 (IGF-1), cortisol, adrenocorticotropic hormone (ACTH), follistatin and myostatin were measured. The results showed that in the supplementation groups, strength, arm and thigh MCSA, and SMM significantly increased, and PBF significantly decreased (P</=0.05); this change was significant compared to the PL group (P</=0.05). In addition, the results showed a significant increase in GH, IGF-1 levels, the ratio of follistatin/myostatin, testosterone/cortisol (P</=0.05), and a significant decrease in cortisol and ACTH levels (P</=0.05) in the supplementation groups. Hormonal changes in GH, IGF-1, testosterone/cortisol, cortisol, and ACTH levels in the supplementation groups were significant compared to the PL group (P</=0.05). The results showed that CrM and Cr-HCl significantly enhanced the beneficial effects of RT on strength, hypertrophy, and hormonal responses, with Cr-HCl showing no benefit over CrM.