HMB UNDER MAGNIFYING GLASS
HMB – beta-hydroxy beta-methylbutyric acid. HMB is an organic chemical compound in form of short-chain hydroxy acid. HMB is a leucine metabolite and it is produced in the body in limited quantities primarily during catabolism of proteins (which are composed of leucine). As for biological function on this substance, it may be classified as an advanced product of proteolysis (decomposition of a peptide bond), having the ability to inhibit the activity of catabolic enzymes.
HMB – PROTECTION AGAINST CATABOLYSM
Numerous studies conducted on an animal model confirmed information regarding anti-catabolic action of HMB. The main role of this substance consists in inhibiting the activity of catabolic enzymes, mainly ubiquitin, resulting in slowdown of muscle tissue breakdown. This function of HMB is surrounded by the greatest number of myths. Gym amateurs who have used HMB counted only for complete protection of muscle tissue during diets aimed at weight reduction.
Numerous scientific studies showed that HMB has effect on lowering the markers indicative of muscle damage, such as creatine phosphokinase or lactate dehydrogenase. It is assumed that decrease in the activity of these biomarkers is caused by limiting degradation of muscle proteins caused mainly by physical effort. This is extremely significant for the cycles of body mass building where anabolic processes should predominate over catabolic ones. It may be obtained not only by intensification of anabolic processes but also through slowdown/inhibition of catabolic processes (whose minimisation is also important during reduction of fatty tissue). Studies confirming lowering of the activity of listed biomarkers were conducted on the human model, i.a. on the rugby players.
HMB – UNIVERSAL SUPPLEMENT
Despite the fact that HMB has been extensively tested and in numerous cases supplementation effects have been determined, its mechanism of action is still present in the minds of scholars from the entire world. Numerous studies show additional positive effects resulting from supplementation with HMB. It is suggested that apart from the effect on the enzyme – ubiquitin – HMB may also have impact on expression of insulin-like growth factor (IGF-1) which was scientifically confirmed in studies conducted on mouse model during which Gerlinger-Romeo et al. revealed an increase in the level of hepatic mRNA which encodes IGF-1 as well as of IGF-1 itself in the plasma of rats subjected to HMB supplementation.
Suggested effect on HMB supplementation on activity of mTOR kinase should also be emphasised. Initially, it was believed that as leucine metabolite HMB will have similar impact on mTOR kinase. Eley et al. noted stimulation of muscle protein synthesis during the incubation of mouse myoblast cells with HMB. Observations made by the researchers confirmed the hypothesis that HMB has effect on activation of mTOR kinase pathway. Additionally, studies performed by research team under the direction of Zanchi revealed beneficial effect of HMB supplementation on synthesis of muscle cholesterol.
Such broad spectrum of action of this supplement makes it extremely versatile, significant during periods of building muscle mass and reducing body fat. Furthermore, supplementation with HMB is not only important for athletes but may be considered as interesting healthy and anti-cancer supplement. The studies conducted by Flakoll et al. confirmed positive effect of HMB (in combination with arginine and lysine) on increase in mass and muscle strength in older people (over 60 years old!); the results have been confirmed by other research teams.
As you can read above, HMB supplementation may entail positive effects for both hard-training people and those who simply care about their health. It should be noted that HMB supplementation should complement well-balanced diet and basic supplementation, which should include vitamins, minerals, healthy fats and in the case of people who practice sports – other specialist preparations. Proposed doses of HMB amount to 8g per day, but acc. to the experts the dose should range from 80-100 mg/kg bm. It should be emphasised that we should be guided towards higher supply during intense training. You train hard, do you?
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