ß-Hydroxy ß-methylbutyrate (HMB) is a metabolite of the essential branch chain amino acid leucine, claimed to decrease muscle protein breakdown associated with exercise, increasing muscle mass and strength development associated with resistance training. HMB is also claimed to reduce muscle damage/soreness, enhancing recovery. Much of the initial research on HMB focused on animals, assessing the effect on carcass mass and quality, immune function, morbidity and mortality, colostral milk fat content, growth rates, safety and toxicity. Despite unconvincing results in animal research, HMB supplementation was applied to humans in the mid 1990’s under the presumption that it may enhance gains in muscle size and strength while reducing muscle damage and soreness associated with resistance training and possibly enhance aerobic capacity.

Should you take HMB? Click here to access the fact sheet on HMB supplementation.