myHMB Science and
Clinical Research

This recent meta-analysis was conducted on the effects of HMB in younger men participating in resistance-training programs.  The data were broken into trained and untrained subject groups. The authors concluded that HMB supplementation resulted in clear overall increases in strength in men entering a resistance training program, but that the benefit of HMB in trained athletes was smaller.

In this 9-week, randomized, double-blind, placebo-controlled study, HMB improved body composition and decreased fat mass which resulted in a substantial increase in lower body strength.

In this year-long, double-blind, placebo-controlled study in the elderly, daily supplementation with HMB, arginine, and lysine resulted in improved body composition and protein turnover.

This randomized, double-blind, placebo-controlled study tested the effects of EAS Muscle Armor® (main ingredients HMB, arginine and glutamine) in resistance-training men in a 12 week study.  This study showed that supplementation with Muscle Armor® improved the effects of the training on improving body composition and increasing fat loss compared with placebo supplementation. Muscle Armor® beneficially improved hormonal markers associated with intense resistance exercise and improvement in body composition.  Muscle Armor® also resulted in greater increases in strength, power, thigh circumference, and decreased indicators of muscle damage.

This in vitro study of HMB on muscle cells showed that HMB affects myoblast differentiation and survival similar to IGF-1 and suggests that HMB has a positive role in preventing muscle wasting.

Lipopolysaccharide (LPS) was used to simulate an endotoxemia model of muscle wasting in cultured muscle cells.  HMB was shown to attenuate the LPS-induced protein degradation. HMB attenuated the activation of caspase-3/-8, activation of dsRNA-dependant protein kinase, and production of reactive oxygen species.  This study further defined the mechanism whereby HMB may attenuate protein degradation in muscle wasting.

HMB supplementation was given either pre- (60 min to allow blood levels to increase) or post-exercise to college-aged men performing acute isometric exercise by maximal voluntary contraction of the quadriceps and hamstrings.  Taking HMB pre-exercise prevented an increase in lactate dehydrogenase (LDH), an indicator of muscle damage. Therefore this study indicated there was an advantage to taking HMB pre-exercise.

In this study tissue as well as whole body protein turnover was studied in rats after HMB administration.  This study demonstrated that HMB inhibits proteasome dependent proteolysis in skeletal muscle and decreases whole body protein turnover.

This review finds that HMB is one of the safest and supplements for increasing athletic performance.  These authors review current studies of HMB use in critical care situations and suggest further studies could show HMB to be of benefit in treating post-intensive care unit weakness.