Background: Supplementation with ß-hydroxy-ß-methylbutyrate (HMB) is becoming a common practice for top athletes. Since the mid-nineties, this supplement vigorously engaged in a worldwide professional literature.
Producers of food supplements do not have any doubt about positive effects of HMB, particularly increase of strength performance, muscle mass, reduction of body fat and rate of recovery after vigorous sports activity. In recent works, the mechanism of acting HMB is mainly explained by its intervention into different signal pathways of protein synthesis, respectively proteolysis (e.g.
NF-B, mTOR respectively PIF or MAPK). Objective: The aim of our review was to summarize and evaluate objectively the effect of HMB supplementation on sports performance based on the latest knowledge of the world literature.
Methods: We used the internet search engine of professional works Google Scholar and searched expert publications from 1990 to the present with the help of the key words. Only the doubleblind studies with a control group and a placebo were chosen.
Results: We found 112 studies of required quality and five reviews. The first meta-analyses containing only a few studies came to contradictory conclusions.
Most of present studies confirm the positive effect of HMB on athletic performance. The studies which did not confirm any positive effect of HMB were applied either to top athletes or lasted only a short time.
Conclusions: According to the up-to-date world literature, HMB increases strength performance, facilitates muscle growth, accelerates regeneration of muscle cells, acts against overreaching and improves body composition by significant loss of adipose tissue.