The branched chain amino acids (BCAA’s) leucine, isoleucine and valine make up more than one third of muscle protein. Leucine is the most researched of the BCAA’s due to its important role in protein metabolism, glucose homeostasis, insulin action and recovery from exercise. HMB is a metabolite of leucine (which means it is a product of the breakdown of leucine) and is taken in supplementary form to increase muscle mass, strength and resistance to damage when combined with resistance training. It is also associated with enhancing endurance and aerobic performance.
HMB is a nutrient which can be obtained in small amounts from various foods including catfish, grapefruit, citrus fruits and breast milk as well as the HMB produced by the body.
HMB is often overlooked or judged as ineffective by potential customers and this has a great deal to do with the public relations disaster which introduced HMB to the market many years ago. Former EAS owner Bill Philips compared HMB to anabolic steroid Deca-Durabolin which built up unrealistic expectations of the new supplement for athletes and body builders. In reality, HMB is not like steroids in effect or results and this caused it to be branded as ineffective while behind the scenes researchers were finding many positive results for HMB supplementation. Not only this, HMB was overpriced when it was introduced but it is now a very cost effective supplement choice.
HMB supplements help to slow down a process call proteolysis, which is the natural process of breaking down muscle tissue that occurs after intense physical activity. Most people take HMB to enhance effects of training on muscle size and strength by optimising time spent in an anabolic state.
The following benefits are associated with HMB supplementation:
- Increased gains of lean muscle
- Preservation of lean muscle when cutting
- Prevention of muscle catabolism
- Reduction of delayed onset of muscle soreness (DOMS) 24 hours post-exercise
- Enhanced body fat reduction
- Decreased total cholesterol (particularly LDL)
- Decreased systolic blood pressure
- Increased VO2 max and endurance
- Improved mood
HMB has been subject to extensive clinical study and support for this supplement is very positive. Placebo-controlled mass studies have shown that HMB increased strength gains, VO2 max and muscle mass gains compared with individuals on the same training regime without ingesting HMB. HMB is shown to be most effective in untrained individuals and the elderly, meaning that not only does it offer itself to a wider market; it is an ideal addition to a supplement stack for those looking to change their lifestyle and body composition for the better this year.
Like with all nutrients, the amount an individual requires varies dependent on bodyweight, gender and activity levels. In general, if you weigh 60kg or less 2g per day is sufficient. If you weigh more than 60kg, a dosage of up to 4g per day is recommended. Only ~1g of HMB should be ingested at any one time and so timing for taking this supplement should be spread across the day, ideally with one 30-45 minutes prior to training.
Supplementing the diet with 1.5-3g/d of calcium HMB during training has been typically reported to increase muscle mass and strength particularly among untrained subjects initiating training with gains typically 0.5-1kg greater over a 3-6 week period than individuals who did not take HMB.
HMB has been well tolerated in all clinical studies with no significant adverse side effects known. Short term studies have found that even 6-8g of HMB per day is not harmful; however the lack of long term studies in this area mean this level of ingestion is not advisable for untrained or amateur athletic individuals.
HMB is commonly supplemented alongside protein, creatine, glutamine and carbohydrate. The best results are seen when it is consumed with creatine, as the two supplements are said to exert a cumulative effect. Stacking creatine and HMB has a positive effect on training as you provide your muscles with the power to work harder while minimising muscle breakdown and reducing recovery time. An example stack would be taking 1g HMB 30 minutes prior to training with 5g creatine monohydrate followed by 20-25g whey protein post-training.
Wilson GJ, Wilson JM, Manninen AH, Effects of beta-hydroxy-beta-methylbutyrate (HMB) on Exercise Performance and Body Composition Across Varying Levels of Age, Sex and Training Experience, Nutrition and Metabolism, 2008, 5(1); DOI: 10.1186/1743-7075-5-1.
Van Someren KA, Edwards AJ, Howatson G, Supplementation with beta-hydroxy-beta-methylbutyrate (HMB) and alpha-ketoisocaproic acid (KIC) reduces Signs and Symptoms of Exercise Induced Muscle Damage, International Journal of Sport Nutrition and Exercise Metabolism, 2005, 15(4): 413-24.
Jowko E, Ostaszewski P, Jank M, Sacharuk J, Zieniewicz A, Wilczak J, Nissen S, Creatine and HMB Additively Increase Lean Body Mass and Muscle Strength during a Weight-Training Program, Nutrition, 2001, 17(7-8):558-66.