Clear Muscle is MuscleTech’s most recent alleged breakthrough and contains just one ingredient: BetaTOR® (Free acid beta-hydroxy-beta-methylbutyrate)…FIND IT HERE
HYDROXY METHYLBUTYRATE (HMB)
Hydroxy Methylbutyrate (HMB) is a metabolite of the Branched Chain Amino Acid, Leucine, and research indicates that about 5% of Leucine is converted into HMB once inside the body. HMB supplementation has been studied primarily as an anti-catabolic agent, though MuscleTech expands upon this claim.
FORMS OF HMB
There are two basic forms of HMB, the calcium salt form (commonly referred to as Calcium HMB), and the free acid form (commonly referred to as HMB-FA).
A 2011 study, published in the “British Journal of Nutrition”, found that the HMB-FA demonstrated superior absorption compared to the same dose of Calcium-HMB. For Clear Muscle, MuscleTech uses a patented form of the HMB-FA known as BetaTOR. Calcium-HMB has been the subject of several studies, which have returned mixed results across the board.
HMB-FA, on the other hand, has been studied much less extensively than its seemingly less effective counterpart, and has demonstrated some impressive efficacy with regards to increasing strength and lean muscle mass.
A 2013 study, published in the “Journal of the International Society of Sports Nutrition”, found that HMB (3g daily) was able to increase strength and lean body mass quite significantly over the course of the study, as well as partially attenuate a decrease in these measures during the “over-reaching phase”.
However, a slightly earlier 2013 study, published in the “British Journal of Nutrition”, failed to produce similar results with short term supplementation of HMB-FA, indicating that prolonged supplementation (several weeks) is required for this form of HMB to effectively increase strength/lean muscle. Calcium-HMB has failed to produce these effects (as evidenced in a 2009 study), indicating that HMB-FA is a far superior form.
A 1996 study from the “Journal of Applied Physiology” noted HMB supplementation partly reduced exercise-induced proteolysis (protein breakdown) which resulted in greater strength gains in both resistance-trained men as well as non-resistance trained men. As mentioned above, HMB-FA has been demonstrated to significantly reduce muscle breakdown resulting from intense exercise, as well as muscle-atrophying diseases.
MUSCLE GAIN (PROTEIN SYNTHESIS)
A 2013 study, published in “The Journal of Physiology”, directly compared the muscle protein stimulating effects of Calcium-HMB to those of Leucine. The results of this particular study showed that while both substances were effective at stimulating muscle protein synthesis, Leucine was more effective on a gram per gram basis than Calcium-HMB.
However, these results directly conflicted with those of a much earlier (2001) study in which Calcium-HMB supplementation failed to meaningfully increase muscle protein synthesis, as well as strength and power output over a 6 week period.
A 2003 study from “The Journal of Strength and Conditioning Research” found no significant changes in lean body mass, strength, or fat mass over a 4 week period, using 3 grams/daily in college athletes. The researchers in this particular study concluded that “Very little clinical evidence exists for supplementing Calcium-HMB in athletic populations”.
A 2009 meta-analysis, which sought to compare the effects of Calcium-HMB supplementation between trained lifters and non-trained lifters, looked at a total of 9 separate studies involving close to 400 subjects in total. This particular analysis specifically looked at strength, body composition, and muscle growth resulting from HMB supplementation and concluded that, while HMB can increase strength in non-trained lifters, these effects were trivial in trained lifters.
The conclusions drawn by the authors of this meta-analysis were roughly in-line with those of a 2008 review which concluded that, while various studies have demonstrated the efficacy of HMB with regards to performance enhancement, there are also several studies which have found it to be ineffective. The authors note that this is likely due to extreme variability between participants, sample sizes, over-training, and duration of experiments.
Ultimately, results with HMB with regards to lean mass gains appear to be hit or miss, and it has very low reliability with regards to this effect when compared to say, Creatine. However, it should be noted that very few studies have used the free acid form of HMB, so any failures with Calcium HMB are not indicative of HMB-FA.
THE BOTTOM LINE
The research on HMB in general is mixed, though the research specifically on HMB-FA is promising thus far. HMB (either form) is actually quite effective at reducing muscular breakdown, and is significantly more potent than Leucine in this respect. Since about 5% of Leucine is converted into HMB once inside the body, it is hypothesized that HMB is responsible for the muscle-sparing effect of Leucine. At about 85 cents per serving, Clear Muscle (HMB-FA) is 2-3 times more expensive than standard Calcium-HMB, though based on the most recent (2013) study mentioned above, this premium may be worth it. The thing to keep in mind is this: HMB-FA produced some truly incredible results in one study, but that is just one study. Clearly the results of that study warrant further research, but until that research is published, we can’t draw any solid conclusions.
[expand title=”REFERENCES” tag=”h5″]
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