Influence of β-Hydroxy-β-methylbutyrate on predominantly white and red muscles of rats not submitted to physical exercise

This study evaluated the influence of β-hydroxy-β-methylbutyrate (HMB) on the body weight and morphometry of white and red muscle fibers of sedentary rats. 29 male rats were divided in: initial control group (ICG ) (n = 5), euthanized at study onset, and three treated groups (n = 8 each): placebo control group (PCG) received saline for 4 weeks; experimental group (EG) received 0.3 g kg -1 of HMB daily and controlled diet; and experimental group  ad libitum , (EGA) received 0.3g kg -1 of HMB daily, without food restriction. There was no difference in food intake and body weight between treated groups. For the EDL muscle, treated groups were different from ICG. Concerning the soleus muscle, no treated group was different from each other and only the EGA presented difference compared to the ICG. Data also did not reveal correlation between the variables food intake and body weight. HMB did not change the body weight or morphometry of EDL muscle fibers. However, the HMB combined with  ad libitum  feeding was able to change the morphometry of soleus muscle fibers.