Effects of MSTN in the absence or presence of leucine, HMB, or creatine on the expression of MSTN-related mRNAs. Legend: Data are presented as means ± standard error (n = 6–9 plates per treatment). Effects of MSTN with or without each ingredient on the mRNA expression of explicit atrogenes (A), MSTN signaling repressors (B), and MSTN transcriptional targets (C). Sub-figures D and E demonstrate that Akirin-1/Mighty mRNA expression was modestly-to-strongly correlated with measured hypertrophy variables. Sub-figure F shows that Akirin-1/Mighty mRNA expression was modestly correlated with the early differentiation marker MyoD mRNA. One-way ANOVA with LSD post-hoc comparisons performed in sub-figures A/B/C; difference superscript letters = p < 0.05. In sub-figure C, ** indicates that MSTN down-regulated MyoD mRNA compared to all other groups (p < 0.01).