What Is It?
HMB (short for β-Hydroxy β-Methylbutyrate) is a metabolite of leucine. Leucine, as you may already know, is one of the 3 branched chain amino acids. HMB seems to be the main metabolite of leucine that protects against muscle breakdown, appearing to be around 20x more potent than leucine.
HMB is not an anabolic (muscle building) supplement, but an anti-catabolic (preventing muscle breakdown) one. This means that, hypothetically, people who are at higher risk of losing muscle mass will see the most benefit from using it. This includes people dieting on low calories and people completing high intensity cardio.
One study by Wilson et al. (2013) on resistance trained men found decreases in muscle protein breakdown approaching significance and concluded that HMB given to trained athletes before exercise can blunt increases in muscle damage.
1-3g/day taken around training.
Stack HMB with creatine to increase lean mass and strength at the same time!
Other measures that can be put in place to prevent muscle breakdown include a high protein diet. Invest in a quality protein powder to consume post-workout.