What is HMB?
Beta-Hydroxy-Beta-methylbutyrate (HMB) is a derivative of the essential amino acid leucine and its metabolite alpha-ketoisocaproate (KIC). HMB is very well studied and there have been numerous scientific publications that show it has anabolic, lipolytic, and recovery boosting effects. In fact, the evidence supporting HMB is so strong that its benefits are as well documented as creatine.
Where Does HMB Come From?
HMB is naturally synthesised within the body from the amino acid leucine. Although leucine is a branched chain amino acid valuable for bodybuilding in its own right, the conversion of leucine to HMB extremely inefficient. It is necessary to consume 60 g leucine to net 3 g HMB (Wilson et al, 2008). Consequently it is extremely difficult to obtain 3 g HMB from diet alone. HMB naturally occurs in small concentrations in citrus fruits and cat fish. However, these concentrations are inadequate for boosting performance.
It has been hypothesised that HMB works by stabilising the cell membrane of muscle cells and/or reducing protein catabolism pathways (Wilson et al, 2008). Basically, it appears to have a protective effect on muscle tissue.
HMB Benefits for Strength
It has been found that HMB supplementation is able to increase the strength of untrained men proportional to dosage (3 g/day giving the best results). The supplemented participants increased their one rep max bench press by 300% more than unsupplemented people (Nissen et al, 1996a). Another study found that although one rep max values did not increase from HMB, the supplement was successful in increasing the maximum pulling force of muscles (Gallagher et al, 2000). These effects also seem to stack with the benefits of creatine (Jowko, 2001). The effect of HMB on increasing strength has also been shown in trained athletes, giving an increase of 55% over unsupplemented athletes (Nissen, 1996b; Panton et al, 2000).
HMB Benefits for Lean Mass Gains
It has been found that after three weeks of HMB supplementation in conjunction with weight training, untrained subjects were able to put 300% more lean mass than the unsupplmented group (Nissen et al, 1996a). Findings such as this have been supported by other researchers (Gallagher et al, 2000; Jowko, 2001). Likewise, with strength gains, the effect of HMB works in complement with creatine (Jowko, 2001). Again, gains have been observed among both the trained and untrained (Nissen, 1996b; Panton et al, 2000).
HMB Benefits for Fat Loss
In all the above mentioned studies where lean gains were present, fat loss from HMB supplementation were found to be significantly higher compared to unsupplemented groups. Additionally, in people with high cholesterol, HMB supplementation has been found to be effective in lowering bad LDL and total cholesterol (Nissen, 2000).
HMB Benefits for Recovery
Another benefit of HMB is its ability to reduce muscle damage and protein degeneration as a result of exercise (Nissen et al, 1996a; Gallagher et al, 2000). Consequently, this may result in improvements in recovery time and reductions in delayed onset muscle soreness (DOMS), which has been confirmed in a study among supplemented individuals (Van Someren, 2005).
HMB Benefits for Bodybuilders and Weight Loss
From the above effects of HMB, it can be seen that this compound may be of great value to bodybuilders and those wishing to lose weight. HMB has been well documented to be able to increase muscle mass, decrease fat mass, and speed up recovery time when used in conjunction with weight training. All these properties may help them you get bigger and leaner quicker. Additionally, it helps to prevent heart disease by reducing cholesterol.
HMB Benefits for Beginner Bodybuilders
If you're new to lifting or bodybuilding, HMB is definitely one of the supplements you should consider. There have been some suggestions that the effects of HMB are amplified, and more rapid among novices and nontrained individuals compared to more experienced athletes. The reason for this is possibly because nontrained individuals experience more muscle damage from exercise compared to their more experienced counterparts (Wilson et al, 2008). Thus, HMB is more able to work its magic in protecting from muscle damage.
HMB Safety and Side Effects
HMB is a product of normal metabolism, it is water soluble, and an excess can be excreted in the urine. Its safety has been evaluated in many studies, which showed that the consumption of 3 to 6 g/day over several months showed no side effects. Studies with animals consuming huge amounts of HMB (up to the equivalent of 450 g/day for a 90 kg man), for up to 16 weeks, also showed no harmful effects (Wilson et al, 2008). If anything, the only reported effect of HMB on health has been positive.
HMB Recommended Doses and Ingredient Timing
It has been recommended by numerous studies that a dose of 3 g/day (as 1 g portions, three times per day) was most beneficial. Studies with people consuming 6 g/day showed no added benefits (Gallagher et al, 2000).
The ergogenic effects of HMB stacks well with creatine. Consider adding HMB to your pre, intra, or post workout supplement if it is not already in it.
Summary of HMB and Recommendations
There is a wealth of information to show that Beta-Hydroxy-Beta-methylbutyrate (HMB) is effective in increasing strength, lean muscle gain, fat loss, and even improving overall health. It manages to do so in the absence of side effects, and is readily available as a supplement. It shows many benefits for bodybuilders, athletes, as well as those wishing to get fit and/or lose weight. In this author's opinion, HMB is a highly recommended supplement. Add it to your wish list if you are not already using it!
Coelho C, Carvalho : Effects of hmb supplementation on ldl-cholesterol, strength and body composition of patients with hypercholesterolemia. Medicine & Science in Sports & Exercise, 33: M340
Gallagher et al (2000), β-hydroxy-β-methylbutyrate ingestion, part I: Effects on strength and fat free mass. Med Sci Sports Exerc, 32: 2109-2115
Jowko (2001), Creatine and β-hydroxy- β-methylbutyrate (HMB) additively increase lean body mass and muscle strength during a weight-training program. Nutr, 17: 558-566
Nissen et al (1996a), Effect of leucine metabolite beta-hydroxy-beta-methylbutyrate on muscle metabolism during resistance-exercise training. J Appl Physiol, 81: 2095-2104
Nissen et al (1996b), Effect of β-hydroxy- β -methylbutyrate (HMB) supplementation on strength and body composition of trained and untrained males undergo-ing intense resistance training. FASEB J 1996, 10:287.
Nissen et al (2000), β -Hydroxy-β-Methylbutyrate (HMB) Supplementation in Humans Is Safe and May Decrease Cardiovascular Risk Factors. Journal of Nutrition, 130: 1937-1945
Panton et al (2000), Nutritional supple-mentation of the leucine metabolite beta-hydroxy-beta-methylbutyrate (hmb) during resistance training. Nutr, 16: 734-9
Van Someren (2005) Supplementation with [beta]-hydroxy-[beta]-methylbutyrate (HMB) and [alpha]-ketoisocaproic acid (KIC) reduces signs and symptoms of exercise-induced muscle damage in man. International Journal of Sport Nutrition & Exercise Metabolism, 15: 413-424
Wilson et al (2008), Effects of beta-hydroxy-beta-methylbutyrate (HMB) on exercise performance and body composition ac ross varying levels of age, sex, and training experience: A review. Nutrition & Metabolism, 5: 1 (online)