In scientific terms, HMB, or β-hydroxy β-methylbutyrate, is a metabolite of L-leucine, which helps maintain balance between the pace of muscle protein regeneration and degeneration. Many bodybuilders and weightlifters use it is a perfect way to increase their dry body mass. Although opinions on the product are divided, it is good to know what the scientists have found out about the substance and learn what can be achieved with the aid of HMB, how to supplement it correctly or whether it is only restricted to athletes.
What do we know about HMB?
β-hydroxy β-methylbutyrate enhances proper physiology of cellular processes, as it participates in the synthesis of cholesterol, which constitutes 13% of the overall content of cell membranes and ensures their proper liquidity. How the cell membranes work highly depends on cholesterol synthesis. Even minor damage to muscle cell membranes increases the demand for cholesterol or, in other words, for the lipid layer. It is HMB that ensures the appropriate cholesterol supply to muscle membrane cells. Knowing that when exercising or weightlifting you expose your muscles to all kinds of micro-injuries, you may want to consider HMB supplementation to protect your muscle cells.
Let us now have a closer look at anabolic and catabolic processes in our bodies. Anabolic processes are processes to produce energy from the food that you deliver to your body. Catabolism, in turn, occurs when the body does not receive the sufficient amount of nutrients and starts to “burn itself”; when too long, catabolism can be hazardous to the health. HMB protects the body against catabolic processes, inhibits protein degradation and restrains the activity of free radicals and enzymes responsible for apoptosis.
As shown above, HMB produces direct physiological effects, i.e.:
- is a perfect supplement during periods of weight loss,
- improves strength in persons with different fitness levels,
- enhances increase in dry body mass,
- allows to retain much more muscles,
- shows anti-catabolic effect.
HMB. Opinions of scientists.
Is HMB an effective workout supplement? Apparently, β-hydroxy β-methylbutyrate has as many opponents as it has supporters. Research devoted to HMB is continuously criticised for being based on a too small research group. It is also emphasised that the selection of performance tests leaves a lot to be desired. Among the examples quoted as a confirmation of the above-mentioned thesis is the test carried out among rugby players in a pending season. The antagonists noted that the performance tests were performed at random and did not have much to do with the real physical strain imposed on the players during games.
Another allegation was that the research did not include mental factors, such as motivation of the players, their self-consciousness, emotional condition or social status, while all of these have the capability to intensify muscle work.
However, when it comes to research conducted among cyclists, these charges had no raison d’être, as in this group, improved fitness after taking HMB was reported also by the athletes themselves.
How to take HMB?
Many are searching for ways to improve their workout routine. If you are in this group, consider taking β-hydroxy β-methylbutyrate. The mechanisms of action of HMB are rather simple and comprehensible. But still, an important question must be asked, i.e. the one about the permissible dose. Scientists assume that our body needs 3 grams of β-hydroxy β-methylbutyrate to make good use of the substance. Lower doses were ineffective, but, most interestingly, supplementation with 6 g did not result in strength improvement and did not enhance the building-up of lean mass either.
The suggestion to adjust the dose to individual needs of the persons practising sports is based on the assumption that the optimum dose of HMB equals 38 mg/kg of lean body mass. Additionally, the specific intensity of catabolism in each individual should be taken into account. It is an interesting point that experienced bodybuilders, who participate in world competitions, take 125 mg of HMB per one kg of lean body mass. Nonetheless, this information is unofficial and cannot be considered decisive.
Can HMB supplementation produce serious consequences? Studies performed on animals fed with 5 g of HMB per one kg of lean mass for 16 weeks did not show any side effects, which makes HMB an extremely safe supplement. When it comes to human doses, data show that a dose of 6 g/day taken for 8 weeks is safe both for those who exercise regularly and for persons who do not do any sports. No increased activity of hepatic enzymes, changed lipid profile or liver function have been reported.
To fully use the potential offered by β-hydroxy β-methylbutyrate, you must know its digestion time. Digestion of HMB takes c.a. 160 minutes, which is very short. Therefore, the substance must be taken several times a day (at least three). You should aim to have the highest HMB concentration when starting to exercise, as then it will fully protect your muscle cells. One-time consumption of 3 g of HMB results in 60 minutes of high concentration of the substance, which means that it should be taken 30-40 minutes before working out. To better illustrate the action of β-hydroxy β-methylbutyrate, let us say that one-time consumption of 1 g of HMB pre-workout reaches peak concentration after c.a. 120 minutes.
Yet, it must be remembered that the first of the above-mentioned doses is used up by the body in 70% only, while lower doses are used in nearly 90%, with the remaining 10% being excreted in urine. This very same research shows that when the stomach is overloaded, the capacities of β-hydroxy β-methylbutyrate are used slower.
HMB not only for athletes
Since β-hydroxy β-methylbutyrate has been proved to be effective on the cellular level and to have a protective effect on the cells, the curative potential of the substance should be looked closer at. HMB can be successfully used when maintaining a specific lean body mass translates directly into the patient’s health and well-being. The target group here includes permanently immobilised or chronically ill persons, or patients undergoing lengthy rehabilitation with muscle atrophy. It has been proved that HMB supplementation effectively inhibits muscle fibre degradation. In other cases, HMB effectively slows down the loss of physical fitness when under prolonging functional immobilisation. HMB can be successfully used in patients hospitalised because of a chronic illness; although their muscle performance will not grow, with HMB it will decline more slowly.