HMB Supplementation

[MCWTRAINER]

This is a product that I personally doesn't feel works but here is some information for everyone to read...


HMB (beta-hydroxy beta-methylbutyrate) FAQ

What is HMB? HMB is a metabolite of the branched chain amino acid Leucine. HMB is not a steroid or a drug but is a classified as a dietary supplement. It is found in foods (vegetables and meat) and is also manufactured by the body.

Why should I consider supplementing with HMB?

HMB appears to increase the body's ability to build muscle and burn fat.
HMB has been shown to have a positive effect on protein metabolism.
Human studies show only positive effects on health and metabolism.
HMB is thought to minimise protein breakdown when combined with resistance-training and may cause an increase in muscle mass and strength.
It is suggested that taking 1 gram of HMB with 1 gram of Vitamin C, 1 hour before training, minimises muscle soreness and improves recovery times.
HMB is thought to aid preservation of muscle tissue when dieting.
Are there any side-effects to HMB supplementation?
Studies to date show no adverse effects to HMB supplementation.

Which Foods are high in HMB?
The following foods contain a high concentration of HMB

Catfish
Grapefruit
Please note that these foods do not contain enough HMB to be realistically considered as a method of HMB supplementation.

What are the recommended doses for HMB supplementation?
It is suggested that 3 grams of HMB per day is optimal for mass and strength gains. However, some research suggests that, for people who weigh 200 pounds or more, doses of up to 6 grams per day are required to see results.

Does HMB work?
There is a large group of people who would be considered seasoned lifters who have posted in both MFW & URB and firmly stated that they found HMB to be of no benefit whatsoever. Whilst research from the ISURF program (who own the patent on HMB) appears to prove that HMB works one cannot discount the "real world" evidence of everyday athletes. It must be noted that there are people who swear by HMB - you must make up your own mind. Research funded by Supplement Co's or individuals with an interest in the sale and marketing of HMB have found HMB to be effective. HMB does not appear to be supported by anything like as much research as Creatine and the research supporting HMB is not as detailed nor was it as widely accepted by their peers in journals and reviews etc. It should also be noted that Creatine can help maintain muscle mass.

[MCWTRAINER]

Hydroxymethylbutyrate (HMB)

The leucine metabolite hydroxymethylbutyrate (more exactly the calcium salt of b -hydroxy-b -methylbutyric acid) has recently become a popular dietary supplement purported to promote gains in fat-free mass and strength during resistance training (Kreider, 1999). The rationale is that leucine and its metabolite a -ketoisocaproate (KIC) appear to inhibit protein degradation (Nair et al., 1992; Nissen et al., 1996), and this anti-proteolytic effect may be mediated by HMB. Animal studies indicate that approximately 5% of oxidized leucine is converted to HMB via KIC (Nissen et al., 1994; Van Koevering et al., 1994). The addition of HMB to dietary feed improved colostral milk fat and growth of sows (Nissen et al., 1994), tended to improve the carcass quality of steers (Van Koevering et al., 1994), and decreased markers of catabolism during training in horses (Miller et al., 1997). Supplementing with leucine and/or HMB may therefore inhibit protein degradation during periods associated with increased proteolysis, such as resistance training.

Although much of the available literature on HMB supplementation in humans is preliminary in nature, several recently published articles and abstracts support this hypothesis. Leucine infusion appears to decrease protein degradation in humans (Nair et al., 1992). HMB supplementation during 3 to 8 weeks of training has been reported to promote significantly greater gains of fat-free mass and strength in untrained men and women initiating resistance training (Nissen et al., 1996; Nissen et al., 1997; Vukovich et al., 1997). In some instances these gains were associated with signs of significantly less muscle damage (efflux of muscle enzymes and urinary 3-methylhistidine excretion) (Nissen et al., 1996). Although these findings suggest that HMB supplementation during training may enhance training adaptations in untrained individuals initiating training, it is less clear whether HMB supplementation reduces markers of catabolism or promotes greater gains in fat-free mass and strength during resistance training in well-trained athletes. Indeed, there are several reports of no significant effects of HMB supplementation (3 to 6 g per day) in well-trained athletes (Almada et al., 1997; Kreider et al., 1997; Kreider et al., 1999). More research is needed (Kreider, 1999).

[/\/\ () |) This]

ehhhhh, what is with all the threads?


o and btw great info, i never have to leave bodybuilding.com to find out about any products.. thanks bro

[pu12en12g]

HMB: Overrated, Overpriced, or Overlooked
By: Derek Charlebois

http://www.bodybuilding.com/fun/beast7.htm
http://www.bodybuilding.com/fun/beast9.htm
http://www.bodybuilding.com/fun/beast10.htm

[MCWTRAINER]

Is β-hydroxy- β-methylbutyrate (HMB) the new creatine?
By: Glaucio Scremin, MSS, CSCS
Doctoral Degree Candidate, USSA

Recently an ergogenic aid called β-hydroxy- β-methylbutyrate or HMB, has been commercially marketed as the new performance enhancer for weight lifting and sprint activities. HMB is metabolite of the amino acid leucine and it is naturally synthesized in our bodies (i.e., 0.2 to 0.4 g of HMB/day). Proponents of HMB claim that supra-endogenous quantities of HMB (i.e., 3 to 6 g of HMB/day) reduced exercise induce muscle proteolysis, thereby producing positive effects on strength and body composition which include increased fat-free mass and reduction in fat mass, increase in leg extension, bench press, and total body strength. Empirical evidence on the effects of HMB on athletic performance remains limited, however. When combined with intensive resistance training, HMB has been shown to increase total body strength and fat-free mass in groups of untrained individuals (Nissen, et al., 1996; Slater & Jenkins, 2000). The mechanism of action of HMB remains unknown, however.

Effects of HMB on athletic performance

Oral supplementation of β-hydroxy- β-methylbutyrate (HMB) has been purported as having performance enhancing benefits (Knitter, et al., 2000; Nissen, et al., 1996; Nissen, et al., 2000; Nissen & Sharp, 2002; Slater & Jenkins, 2000). The proposed ergogenic benefits of HMB supplementation include a reduction in exercise induced proteolysis (Nissen, et al., 1996; Slater & Jenkins, 2000) and body fat as well as increases in total body strength and fat-free mass in groups of untrained individuals (Nissen, et al., 1996). All of the demonstrated effects of HMB have emerged in combination with intensive resistance training.

The mechanisms by which HMB impact athletic performance remain elusive. Nissen et al., 1996 have proposed that HMB may serve as a structural component within cell tissues and membranes by covalently binding to cell membrane components and increasing their structural integrity. In support of this hypothesis, muscle proteolytic-indicating enzymes have been shown to be significantly lower in HMB-supplemented subjects when compared placebo-supplemented subjects (Knitter, et al., 2000; Nissen, et al., 1996). However, the exact mechanisms by which HMB inhibits or attenuates muscle proteolysis remain unidentified. HMB positive anabolic effects on muscle strength and muscle mass seem to be due to an overall reduced catabolic state following intense resistance exercise training instead of a direct effect on muscle anabolism.

Research on the effects of HMB on aerobic performance to endurance training is scant. In one such study, Knitter et al., 2000 evaluated the 20-km running performance of a group of experienced male and female distance runners. The results showed that after six weeks of HMB supplementation in combination with endurance training HMB-supplemented subjects exhibited significantly lower plasma concentrations of both creatine phosphokinase (CK) and lactate dehydrogenase (LDH) than the placebo-supplemented group. Knitter et al. concluded that HMB supplementation inhibits endurance exercise-induced muscle damage. Similarly, Vukovich & Dreifort, 2001 have examined effects of two weeks of HMB supplementation on the Onset of Blood Lactate Accumulation (OBLA) and VO2 peak in a group of experienced cyclists. HMB supplementation significantly increased the time to OBLA in the HMB-supplemented group when compared to the placebo-supplemented group. VO2 peak was unaffected by HMB supplementation.

The effects of HMB on anaerobic capacity and intermittent performance have not received any research consideration. Both anaerobic and intermittent activities have been shown to induce significant muscle damage (Mohr & Bangsbo, 2001). Consequently, based on the proposed mechanism of action of HMB, athletes of sports which involve large anaerobic or intermittent performance components may benefit from HMB supplementation.

Conclusions
To date HMB and creatine remain the only two dietary supplements that have been consistently shown to increase lean body mass and improve strength gains when combined with a resistance training program (Nissen & Sharp, 2002). Nevertheless, HMB effects on aerobic, anaerobic, and intermittent performances as well as its mechanism(s) of action remain to be determined.

References
Knitter, A. E., Panton, L., Rathmacher, J. A., Petersen, A., and Sharp, R. (2000).

Effects of β-hydroxy- β-methylbutyrate on muscle damage after a prolonged run. J. Appl. Physiol., 89, 1340-1344.

Mohr, M., & Bangsbo, J. (2001). Development of fatigue towards the end of a high level

soccer match. Med. Sci. Sports Exerc. 33, 215.

Nissen, S. L., Sharp, R., Ray, M., Rathmacher, A., Rice, D., Fulller, J.C.,

Connelly, A.S., & Abumrad, N. (1996). Effect of leucine metabolite β-hydroxy- β-methylbutyrate on muscle metabolism during resistance-exercise training. J. Appl. Physiol., 81(5), 2095-2104.

Nissen, S. L., Sharp, R. L., Panton, L., Vukovich, M., Trappe, S., and Fuller, J. C.

(2000). β-hydroxy- β-methylbutyrate (HMB) supplementation in humans is safe and may decrease cardiovascular risk factors. J. Nutr.,130, 1937-1945.

Nissen, S. L., & Sharp, R. L. (2002). Effect of dietary supplements on lean mass

and strength gains with resistance exercise: a meta-analysis. J. Appl. Physiol.94, 651-659.

Slater, G. J., & Jenkins, D. (2000). β-hydroxy- β-methylbutyrate (HMB)

supplementation and the promotion of muscle growth and strength. Sports Med. 30(2), 106-116.

Vukovich, M. D., & Dreifort, D. (2001). Effect of β-hydroxy- β-methylbutyrate on

the onset of blood lactate accumulation and VO2 peak in endurance-trained cyclists. J. Strength Cond. Res.,15(4), 491-497.

[MCWTRAINER]

Some research studies...
http://www.bodybuilding-supplement-g...e-effects.html

[MCWTRAINER]

HMB

Three major companies (Twinlab, MetRx, and EAS) currently market the nutritional supplement HMB, or beta-hydroxy beta-methylbutyrate (http://www.sports-nutrition.org/meso.../3022645.html). HMB has been highly acclaimed since it’s recent market debut by EAS (http://www.eas.com/research/hmb/mindex.html). Many critics have compared it to the wonder-product Creatine Monohydrate. Such a comparison undoubtedly harbors both positive and negative aspects. But nevertheless, HMB products continue to thrive in nutritional stores worldwide.

I. What is HMB?

"HMB (hydroxy-methylbutraye) is a metabolite of the amino acid Leucine and is produced naturally by the human body. HMB is produced from a metabolite of leucine, called ketoisocaproate (KIC), by the enzyme KIC-dioxygenase. And, at least in the pig, HMB is produced exclusively from leucine"(Nissen p.2095).

II. How does HMB work?

Steven Nissen and his colleagues have performed the only study to date of HMB on humans. The researchers agree that the mechanism by which HMB impacts muscle proteolysis and function is not currently known. Nevertheless there are a number of postulations. "The high substrate concentration required by the dioxygenase enzyme compared with the liver concentration of KIC suggests that HMB production in the body may be a first-order reaction controlled by enzyme and KIC concentrations. It has been calculated that, under normal conditions, about 5% of leucine oxidation proceeds via this pathway. Therefore, if humans are assumed to have enzyme actions similar to those seen in pigs, a 70-kg human would produce from .2 to .4 g HMB/day depending on the level of dietary leucine. At leucine intakes of 20-50 g/day (which are used therapeutically), the concentrations of leucine and KIC in the liver increase and could result in HMB production reaching gram quantities per day"(Nissen p.2095). Some studies involving HMB supplementation to the diet of steers and pigs have been shown to improve caracass quality. Based on these findings, it has been hypothesized that supplementing the diet with HMB may inhibit protein degradation during periods of increased proteolysis such as resistance training.

III. What are the Claims?

The three companies that currently market the product recommend 1.5-3.0 grams of HMB/day as a dietary supplement. Although the science behind the product’s effectiveness is rather unclear, all three companies show few distinctions between dosages and manufacturing. Most people who have noticed the product often see HMB advertised as a protein breakdown suppressor. Researchers claim that such an advantage actually enhances the gains in muscle strength and lean mass associated with resistance training. Companies who promote the product claim that humans neither produce enough HMB in their bodies, nor do they eat such HMB-containing foods (e.g. catfish and grapefruit) regularly enough to provide the full benefits of HMB. Researchers claim that when we input extra amounts of HMB into our bodies the metabolite acts as a performance enhancer for such activities as weight lifting and sprinting. In effect, companies claim that HMB boosts strength levels, enhances gains in muscle size and strength, and prevents post-workout muscle tissue breakdown. The marketing companies do not make exactly clear how the product works, but they have formulated a few widely accepted ideas which are seen on the advertisement postings in many nutritional stores. Many of them believe that excess amounts of HMB in the body cause an interference with the body’s natural process of protein breakdown (particularly after a workout). In doing so, HMB allows athletes to retain more protein in their system, resulting in increased energy levels and faster recovery. Of course the companies claim that this product is only beneficial to those who workout in addition to HMB supplementation. Internet advertisements claim that there are countless experiments involving placebos and HMB supplements, which have resulted in substantial performance increases in the many groups of athletes who have taken HMB along with their training regimen.

IV. First Impressions

In my search for information about HMB, I found that most of the claims and information were fairly similar. Since so few companies actually market the product such a common thread is expected. I did find it interesting however that none of the companies recognized any side effects whatsoever throughout all of the experiments and research of the product. This concern has become all too familiar in the recent explosion of nutritional products. Perhaps there is more to be discovered about HMB in cases of long-term usage.

V. What is the Research Evidence?

As I began searching for information on the 'countless studies' involving HMB and its connection to athletic performance, I noticed that it was rather difficult to pinpoint any studies involving humans. And even the studies on animals were limited. This is more than likely due to the fact that HMB is a relatively new product on the market. The one primary research report on humans that I found was a very popular one. I noticed that many of the review papers used it is a reference tool. The study was conducted by Steven Nissen, and a number of his colleagues in November 1996.

A. Nissen Study

What was the question? Nissen and his colleagues wanted to know what the effects were of HMB on muscle metabolism during resistance-exercise training.
What methods were used? Nissen used two studies to determine the effects that HMB had on muscular metabolism. In his first study, Nissen took a randomized sample of 41 individuals and divided them randomly into three different levels of HMB intake (0,1.5, and 3 g HMB/day) and two protein levels (117 g/day and 175 g/day). In all of the groups the subjects lifted weights for 1.5 hours and three days a week for three weeks.

In the second study Nissen took another random sample of 28 individuals and divided them randomly into two levels of HMB supplementation (0 and 3 g HMB/day). In both groups, the subjects lifted weights for 2-3 hours and 6 days per week for 7 weeks.

What were the results? In the first study, HMB greatly decreased the muscle proteolysis as well as the levels of plasma creatine phosphokinase. Additionally, the amount of weights lifted increased with HMB supplementation when compared with the unsupplemented group. During each week of the second study, fat-free mass was significantly increased in HMB supplemented subjects compared with the unsupplemented group. Nissen and colleagues thus concluded that supplementation with either 1.5 or 3 g HMB/day can partly prevent exercise-induced proteolysis and/or muscle damage. Additionally, the dietary supplementation of HMB can result in larger gains in muscle-mass associated with resistance training.
B. Papet Study (Papet, et al. June 1997)

[MCWTRAINER]

(continued)

What was the question? I. Papet and his colleagues designed an experiment to study the effect of a high dose of HMB on the protein metabolism in growing lambs.
What methods were used? Six two-month old lambs were divided into two groups. The first group was the experimental group and involved the supplementation of a high dosage of HMB and the second group was a control for the experiment using only a calcium compound. In order to effectively study the protein metabolism, Papet used three methods consecutively 2.5 months after beginning the treatment. He used whole body phenylalanine fluxes, postprandial plasma free amino acid time course, and fractional rates of protein synthesis in skeletal muscles.
What were the results? From the second test, Papet and colleagues reported that feeding a high dose of HMB led to a significant increase in some plasma free amino acids compared with the controls. The first method, which tested the phenylalanine flux, proved unchanged in both groups. Similarly in the last test of fractional rates of protein synthesis, both groups showed no change upon examination of skeletal muscles. Collectively, the results manifested that a high dosage of HMB was able to modify plasma free amino acid patterns without any effect on whole-body protein turnover and skeletal muscle protein synthesis. Such an observation suggests that there are no significant protein intake and HMB interactions. This further supports the idea that the effects of HMB on metabolism are additional to and independent of protein intakes. Therefore, even though HMB is a metabolite of leucine, simply consuming more protein containing a large amount of the amino acid leucine would not be comparable to dietary HMB supplementation.
C. Van Koevering Study (Van Koevering, et al. August 1994)

What was the question? Van Koevering and his colleagues designed an experiment in order to determine the effects of HMB on the performance and carcass quality of feedlot steers.
What were the methods used? Van Koevering and his colleagues took a random sample of 256 crossbred steers and divided them into two groups. One group was given .03% of diet dry matter and the other was given 0%. The effects on the performance, carcass characteristics, and tissue composition were measured. Groups of 32 steers per diet were killed after 105, 119, 133, and 147 days on the feed. The HMB was fed to each group only during the final 82 days they were fed.
What were the results? The researchers noticed an interaction between HMB and the time on the feed, in that feeding HMB increased daily gain of steers slaughtered at 105 days, but decreased the daily gain of steers slaughtered at 147 days. Additionally the steers fed HMB had higher carcass quality grades, as well as a higher ratio between fat muscle and skin fat. The HMB steers also had higher blood plasma concentrations of HMB and lower blood plasma concentrations of cholesterol.
VI. Primary Research Wrap-Up

Due to the fact that a limited number of HMB studies have been performed on humans, we must also consider the results of the tests on animals. Perhaps there is a connection between the noted improvements in the two animal tests and those of humans. This data alone, however, is insufficient. Since HMB is a relatively new product, one must take into consideration the possible side effects or other negative aspects of upsetting a natural balance within the body. There were a few review papers that I found expressing both skepticism and praise of HMB as a dietary supplement.

VII. Review Paper Reactions to HMB Studies/Claims

Researchers, Clarkson and Rawson, published an article concerning a number of the nutritional supplements currently on the market and their effect on human muscle mass. Not surprisingly, they spent a good portion of the article on creatine, which was introduced several years ago as a body-building supplement. As a result of its tenure, creatine has much more information available regarding its functions and effectiveness. Additionally there are more studies on creatine than HMB. Nevertheless, the researchers covered most of the supplements including HMB. Although brief, Clarkson and Rawson commented on the performance of HMB as a nutritional supplement. They recognized Nissen's, "preliminary work on HMB and its support of the claim that HMB has an anticatabolic effect on the muscles"(Clarkson p.320). They also emphasized the fact, however, that only one human study is currently available, and therefore the existing data is inconclusive.
Another review of HMB was done by Kreider. His study of the product was similar in fashion to that of Clarkson and Rawson, in that he took a number of dietary supplements and examined whether or not they are effective in the promotion of muscle growth with resistance exercise. He also recognized Nissen's study as well as those on the animals in his commentary. Kreider focused on the dietary supplementation of HMB and its marketers' claim that it promotes gains in fat-free mass during bouts of exercise. He uses Nissen's study to argue that HMB has been shown to positively affect athletic performance. But here again, there is little time spent on the subject of HMB and it's effectiveness. It seems appropriate that comments on the research evidence are sparse, since there is only one human study to date. As a further commentary, a researcher Mero developed an article, which focused on Leucine supplementation and intensive training. However, as yet another roadblock in the way of finding review papers focused on the study of HMB, Mero remarked that there have been very few studies done with Leucine alone. He argues that, "most studies involve leucine supplemented as part of a mixture of another compound"(Mero p.351). The conclusions are therefore not likely to reflect the performance of HMB alone. And again, Mero (like the other authors) referred to Nissen's study as being the only controlled manifestation of HMB's performance on resistance-trained human beings.

VIII. Are There Any Confounding Variables in the HMB Study on Humans?

Since there is only one concrete study of the effects of HMB on the athletic performance of human beings, confounding variables are of great importance. If a lurking variable were to skew the results of Nissen's study then the base of support for the companies claims would be unsubstantiated. Therefore I proceeded with caution when formulating a final opinion on the effectiveness of HMB. In reading through Kreider's review paper on Nissen's study, I found a possible lurking variable. Kreider realized that in the one study that reported significant gains in fat-free mass in resistance-trained athletes, "HMB was added to a popular carbohydrate/protein vitamin/mineral fortified meal replacement supplement"(Kreider p.107). Therefore it is unclear whether HMB supplementation and/or some other combination of nutrients was responsible for the gains in fat-free mass observed. This is undoubtedly an important consideration in reviewing the study, which has the potential to be the basis for a concerned consumer's opinion.

IX. Final Impression

After reviewing the sparse and conflicting information regarding the effectiveness, I came to the conclusion that there is simply not enough concrete evidence to support the claim that HMB promotes the growth of lean muscle mass and reduces proteolysis. This is not to say that the product is unsafe, especially since, to my knowledge, there have been no contradicting studies or documented side effects from the product. I did, however, discover a few of the underhanded marketing techniques used by the companies. They claimed that there were countless research studies, which proved HMB's validity as an effective nutritional supplement. This was not nearly the case. The simple fact that a resourceful university library produced only one study involving HMB on humans, is evidence enough to argue that the promoters are over-generalizing the facts behind the study of the product. The companies backing HMB have made a number of claims that their product is beneficial to resistance-trained athletes. So far there have been no concrete indications suggesting otherwise.

X. References

Nissen S; Sharp R; Ray M; Rathmacher JA; Rice D; Fuller JC Jr; Connelly AS; Abumrad N, "Effect of Leucine Metabolite Beta-Hydroxy-Beta-Methylbutyrate on Muscle Metabolism During Resistance-Exercise Training" Journal of Applied Physiology (November 1996): 2095-2104
Clarkson PM; Rawson ES, "Nutritional Supplements to Increase Muscle Mass" Clinical Review of Food, Science and Nutrition (July 1999): 317-328
Kreider RB, "Dietary Supplements and the Promotion of Muscle Growth with Resistance Exercise" Sports Medicine (February 1999): 97-110
Mero A, "Leucine Supplementation and Intensive Training" Sports Medicine (June 1999): 347-358
Papet I; Ostaszewski P; Glomot F; Obled C; Faure M; Bayle G; Nissen S; Arnal M; Grizard J, "The Effect of a High Dose of HMB on Protein Metabolism in Growing Lambs" British Journal of Nutrition (June 1997): 885-896
Van Koevering MT; Dolezal HG; Gill DR; Owens FN; Strasia CA; Buchanan DS; Lake R; Nissen S, "Effects of Beta-Hydroxy-Beta-Methylbutyrate on Performance and Carcass Quality of Feedlot Steers" Journal of Animal Sciences (August 1994): 1927-1935

[MCWTRAINER]

Does HMB Increase Muscle Size and Strength?

HMB, short for beta-hydroxy-beta-methylbutyrate, is a downstream metabolite of the branched-chain amino acid leucine and its ketoacid alpha ketoisocaproate (KIC). Advertisements for the supplement claim that HMB decreases muscle breakdown after exercise, speeds muscle repair, and increases muscle mass and strength during resistance training.

The claims of reduced muscle proteolysis and increased muscle size and strength are supported by only two studies (published together) by Stephen Nissen, PhD, DVM, and colleagues at Iowa State University in Ames (see Nissen, 1996). In the first study, 41 untrained male subjects (ages 19-29, average weight of 82.7 kg) were randomly divided into one of three groups receiving varying amounts of HMB – 0 (placebo), 1.5, or 3 grams per day. The subjects also ingested one of two different amounts of protein; either a normal level of 117 grams per day (1.4 grams per kg) or a high level of 175 grams per day (2.1 grams per kg). The subjects lifted weights for an hour and a half, three times a week for three weeks.

While not statistically significant, the HMB supplemented subjects tended to gain lean body mass in a dose-responsive manner -- 0.4 kg for the placebo group, 0.8 kg for the 1.5 gram HMB group, and 1.2 kg for the 3.0 gram HMB group. The level of protein intake did not influence body weight change or the amount of weight lifted for any of the exercises. However, the HMB supplemented subjects lifted more weight than the placebo group during all three weeks. The combined HMB groups performed significantly more abdominal exercises (a 50% increase) compared to the placebo group (a 14% increase). Total strength (upper and lower body) increased significantly in both the 1.5 gram HMB group (13%) and the 3.0 gram HMB group (18.4%), compared to the placebo group (8%). HMB improved lower body strength and abdominal strength more than upper body strength.

HMB supplementation was also associated with decreased biochemical indicators of muscle damage. Urinary 3-methylhistidine (3-MH) decreased by 20% and serum levels of muscle creatine phosphokinase (CPK) and lactate dehydrogenase (LDH) fell by 20-60%. The results for the first study suggested that HMB can partially prevent exercise-induced proteolysis and/or muscle damage, thereby promoting greater gains in muscle mass and strength during a resistance-training program.

A second study was conducted to determine whether HMB supplementation would promote changes in body composition and strength over a longer time period (see Nissen, 1996). The 32 male trained subjects (ages 19-22, average weight of 99.9 kg) were randomly divided into two groups receiving either no HMB (placebo) or 3.0 grams of HMB per day. The subjects lifted weights for two to three hours daily, six days a week for seven weeks. By day 14 and through day 39, the HMB supplemented subjects gained significantly more fat free mass than the placebo group. On the last day of the study, fat free mass was not significantly different between the groups. However, HMB supplementation significantly increased bench press strength by almost threefold.

In a review article, Nissen and colleagues suggest that HMB, rather than leucine, is responsible for the well-known anticatabolic actions of leucine (see Nissen, 1997). Approximately 5% of the leucine metabolized by the body is converted to HMB, which provides 0.2 to 0.4 grams of HMB per day. The authors hypothesize that HMB supplies a source of beta-hydroxy-beta-methylglutaryl CoA (HMG Co-A) for cholesterol synthesis by the muscle cell. They propose that muscle cells can’t use blood cholesterol effectively and need to manufacture it internally. In stressful conditions, the muscle cells require greater cholesterol production for the synthesis of new cell membranes or to regenerate damaged membranes of existing cells. Thus, HMB may be important during periods of stress to promote increased muscle cell integrity and function.

The authors note that further data is needed to support this theory and that the exact mechanism behind HMB’s proposed effectiveness depends on future research. They further indicate that HMB is safe, does not cause adverse physiological or psychological effects, and does not alter any indicators of organ or tissue function.

Advertisements for the supplement recommend consuming 3 grams of HMB per day. The ads also suggest using a dietary supplement containing "pure" HMB, since it is extremely difficult to consume enough foods high in HMB (alfalfa, corn silage, grapefruit and catfish) to obtain the benefits. Lastly, the ads recommend against consuming leucine since 60 grams of leucine are required to obtain 3 grams of HMB. In addition to being impractical, this could cause severe gastrointestinal distress (see Environmental and Applied Sciences website: http://www.eas.com).

Athletes who weight train should not consider HMB a magic bullet. The following points should be considered before taking HMB supplements: 1) the results have not been reproduced by other researchers in other labs; 2) the subjects in the first study by Nissen and colleagues were untrained, so the results cannot be applied to trained individuals or elite athletes; 3) three weeks of HMB supplementation in untrained subjects did not significantly increase muscle mass compared to a placebo 4) seven weeks of HMB supplementation in trained subjects did not increase muscle mass compared to a placebo 5) HMB is expensive -- a ten day supply costs about $34.95; and 6) the Dietary Supplement and Health Education Act of 1994 allows products to be marketed without proof of safety, efficacy, or potency, so there is no guarantee of consistent dosage.



References

Nissen SL et al. Effect of leucine metabolite beta-hydroxy-beta-methylbutyrate on muscle metabolism during resistance-exercise training. Journal of Applied Physiology. 1996; 81(5):2095-2104.

Nissen SL et al. Nutritional role of the leucine metabolite beta-hydroxy-beta methylbutyrate (HMB). Journal of Nutritional Biochemistry. 1997; 8(June):300-311.

[pu12en12g]

Beta-Hydroxy-Beta-Methylbutyrate (HMB)

DESCRIPTION

Beta-hydroxy-beta-methylbutyrate, abbreviated HMB, is found naturally in living matter as a metabolite of the essential amino acid L-leucine. There is preliminary evidence suggesting HMB may have anticatabolic, as well as immunomodulatory, properties. As a nutritional supplement, it is popular among athletes engaged in strenuous physical activity.

HMB is also known as hydroxymethylbutyrate, beta-hydroxyisovalerate and 3-hydroxyisovalerate.

ACTIONS AND PHARMACOLOGY

ACTIONS

HMB has putative anticatabolic and immunomodulatory activities.

MECHANISM OF ACTION

The mechanism of HMB's possible actions is unknown. There is, however, speculation. The branched-chain amino acids L-leucine, L-isoleucine and L-valine are known to be beneficial to catabolic patients (sepsis, trauma, burns, etc.) by improving hepatic protein synthesis and nitrogen economy. These amino acids make up about one-third of muscle protein. Of these amino acids, L-leucine has the highest oxidation rate. Further, L-leucine has been shown to stimulate protein synthesis in muscle, and decreases in leucine levels in skeletal muscle and in serum have been noted following exhaustive exercise. However, L-leucine supplementation has not been found to have a significant effect on athletic performance. It has been speculated that the L-leucine metabolite HMB may be responsible for the inhibitory effect of L-leucine on protein breakdown. How this may happen is unknown.

In pigs, HMB is produced from alpha-ketoisocaproate, a metabolite of L-leucine, via the enzyme alpha-ketoisocarproate dioxygenase, an enzyme that requires oxygen and iron for its activity. This pathway, located in the cytosol, may also exist in humans. L-leucine is also metabolized in mitochondria to produce HMB in the form of HMB-coenzyme A (HMB-CoA), rather than free HMB.

HMB has been found to induce chicken macro****e growth and enhance chicken macro****e function in culture. It has also been found to enhance both humoral and cellular immunity in young broilers. The mechanism of these immunomodulatory activities is unknown.
PHARMACOKINETICS

Little is reported on the pharmacokinetics of HMB in humans. Apparently, HMB is absorbed, and about 50% of an ingested dose is excreted unchanged in the urine. HMB may be metabolized to beta-hydroxy-beta-methylglutaryl-CoA, which is, in turn, metabolized to acetyl-CoA and acetoacetate.
INDICATIONS AND USAGE

It is claimed that HMB can increase lean muscle mass and exercise performance, but this is far from conclusively established. There is the suggestion in some preliminary research that HMB may have some immunomodulating effects.
RESEARCH SUMMARY

One study has reported that HMB-supplemented subjects (receiving 1.5 or 3 grams daily) lifted more weight compared with unsupplemented subjects. The researchers concluded that either dose of HMB "can partly prevent exercise-induced proteolysis and /or muscle damage and result in larger gains in muscle function associated with resistance training."

Because the subjects in the above-described study were initiating training, another group of researchers sought to determine whether HMB might have effects similar to those reported in the first study — but this time in trained athletes. This was a double-blind study in which 40 experienced resistance-trained athletes were randomized to receive 0, 3 or 6 grams of HMB daily for 28 days. No significant differences were noted in whole body anabolic/catabolic status, muscle and liver enzyme efflux, fat/bone-free mass, fat mass, percent body fat, or leg press one repetition maximums(1RM) strength. More research is needed.

Very preliminary research in some animal models suggests that HMB supplementation may improve several immunological functions that may result in decreased mortality in these animals.
CONTRAINDICATIONS, PRECAUTIONS, ADVERSE REACTIONS
CONTRAINDICATIONS

None known.
PRECAUTIONS

Pregnant women and nursing mothers should avoid supplemental HMB.
ADVERSE REACTIONS

None reported.
OVERDOSAGE

No reported overdosage.
DOSAGE AND ADMINISTRATION

Some athletes use 3 grams of HMB daily during periods of training.
HOW SUPPLIED

Capsules — 250 mg, 500 mg, 750 mg

Tablets

LITERATURE

Kreider RB, Ferreira M, Wilson M, Almada AL. Effects of calcium-beta hydroxy-beta-methylbutyrate (HMB) supplementation during resistance-training on markers of catabolism, body composition and strength. Int J Sports Med. 1999; 20:503-509.

Mero A. Leucine supplementation and intensive training. Sports Med. 1999; 27:345-358.

Nissen S, Sharp R, Ray M, et al. Effect of leucine metabolite beta-hydroxy-beta-methylbutyrate on muscle metabolism during resistance exercise testing. J Am Physiol. 1996; 81:2095-2104.

Peterson AL, Qureshi MA, Ferket PR, Fuller JC Jr. Enhancement of cellular and humoral immunity in young broilers by the dietary supplementation of beta-hydroxy-beta-methylbutyrate. Immunopharmacol Immunotoxicol. 1999; 21:307-330.

Peterson AL, Qureshi MA, Ferket PR, Fuller JC Jr. In vitro exposure with beta-hydroxy-beta-methylbutyrate enhances chicken macro****e growth and function. Vet Immunol Immunopathol. 1999; 67:67-78

FYI

[MCWTRAINER]

HMB for muscular strength, density and power.
(22/03/2004 )


HMB (Beta-hydroxy beta-methylbutyrate) is a metabolite of the amino acid Leucine. This means that it is a natural bi-product of the breakdown of leucine, a constituent of normal dietary protein. Small amounts of HMB are found in certain foods like catfish, alfalfa and it is a natural component of mother’s milk, but generally speaking it’s pretty scarce in the average diet. HMB was first discovered in the 1950’s and has been studied for several decades, but only really became popular as a sporting supplement in the mid 90’s.



HMB has been found to slow down the degradation of muscle protein as well as enhance muscle gain, which means that it possesses both anti-catabolic and anabolic qualities. Early research has demonstrated that HMB supplementation lowers harmful blood cholesterol and helps strengthen the immune system too.

The research

HMB supplements were first used in the farming industry to help farmers raise leaner cattle and keep them free from infection. Scientists who studied animals taking HMB found that it increased muscle growth, immune function and reduced subcutaneous fat (the fat stored directly under the skin).

More recent research with human subjects has shown similar benefits. A highly respected research scientist called Dr Steven Nissen and his research team at Iowa State University conducted a study to determine if HMB would prevent muscle breakdown in humans undergoing resistance training and whether differing levels of protein intake would affect muscle mass or strength. They also assessed the effects of training and HMB administration on body fat and lean body mass levels.

The researchers found that HMB supplementation decreased muscle breakdown in the group that took 3grams. Muscle strength also increased by 18.4% in the 3gram group, compared with 8% in the placebo group and muscle mass also increased by 2.66lbs and 0.88lbs respectively.



How does HMB work?

As we have established, HMB is derived from the essential amino acid leucine. Essential amino acids have to be delivered to the body via the diet and usually human HMB production averages around 0.2 to 0.4grams per day, depending on how much leucine is present in the diet. Researchers have experimented with high dietary doses of leucine to see if this results in higher HMB production and although this has worked, for HMB production to reach ‘gram’ quantities, you’ll need 20 to 50grams of leucine per day. Supplementing with these quantities of leucine is incredibly expensive and is likely to upset your stomach. Therefore, supplementing directly with HMB makes for better cashflow and less toilet paper!

In order to establish how HMB might work, researchers have formulated hypothyses and tested them. It is known that HMB improves the protein balance by reducing catabolism (breakdown) and increasing anabolism (build-up) of muscle, but it is not fully understood how this occurs. It was first though that HMB might be blocking the enzymes that carry out this catabolic process or that HMB itself may be an integral part of the cell membranes. Whilst neither of these hypotheses has been ruled out, scientists now believe that HMB is most likely to be a precursor to a vital component of cell membranes, cholesterol. Rest assured, HMB has also been found to reduce harmful LDL (low density lipoprotein) blood cholesterol levels too, so HMB supplementation could reduce the risk of heart disease as well.

Can we trust the HMB research?

This research is not without it’s controversy. It’s generally recognised that whilst Dr Steve Nissen is a highly respected research scientist, he also holds several use patents on HMB. Some argue that this makes his research lack credibility, because he stands to gain financially from HMB’s success. The counter argument is of course, if you’d discovered a supplement that increases muscular strength by 18.4% over a 3 week period, wouldn’t you want to get the patent on it? Until further research is conducted in this area, we’ll not be able to say for sure, but there are some other very strong indications that HMB could be the amazing product that Dr Steve Nissen has indicated in his research:

1) One of the most highly respected physiologists in the world, Dr Edmund Burke, consultant to Chris Carmichael (Lance Armstrong’s coach) gives the ‘thumbs up’ to 8 specific supplements in his “Serious Cycling”* book and HMB is one of them (the others being caffeine, ribose, glutamine, glycerol, MCTs, L-carnitine and glucosamine). He recommends 3grams per day for cyclists looking to increase strength and power, similar to the 3-5gram dose he suggests for ribose supplementation.



2) Another highly respected author with over 30 years research experience on dietary supplements, Dr Melvin Williams, author of “The Ergogenics Edge”** provides very honest appraisals in his A-Z of sports ergogenics. He covers everything from Alcohol and Amphetamines through to Zinc and there aren’t many supplements he recommends. Of the few he’s reasonably positive about, HMB is one of them. He says “Although the effectiveness of HMB supplementation as an effective sports ergogenic remains to be proven, the preliminary data are somewhat supportive and it appears to be a safe, legal and ethical supplement.” He goes on to say “Endurance athletes who train intensively might benefit if HMB would prevent muscle tissue degradation.” Not a glowing report, but certainly on a par with his conclusions on Creatine supplementation, which is generally acknowledged to work (and without a doubt less beneficial to the endurance athlete).

[pu12en12g]

Also see Leucine / BCAA's / EAA's:

http://forum.bodybuilding.com/showthread.php?t=392907

[MCWTRAINER]

Information and some research...
http://www.powersupplements.com/hmb.htm

[MCWTRAINER]

NUTRITION AND ERGOGENIC AIDS - QUESTION AND ANSWER
By Ted Lambrinides, PhD

Posted on NaturalStrength.com on April 15, 2000

Reprinted with permission of HARD TRAINING

I have been reading in the muscle magazines about a supplement called HMB.
What is it and can it be of any help?

Beta-hydroxy-beta-methylbutyrate (HMB) has emerged as a very hot supplement in the strength training population. HMB is a metabolite (by product) of leucine metabolism. Leucine and a-ketoisocapronate (KIC) are proposed to decrease nitrogen and protein loss by inhibiting protein breakdown and thus are called anticatabolic or antiproteolytic. However, this action in animals and humans has only been shown to occur in situations of severe stress or trauma in which protein breakdown is greatly elevated.

HMB is produced from KIC by the enzyme KIC-dioxygenase and, at least in the pig, is produced solely from leucine. Some researchers feel that HMB is responsible fro the inhibitory effect on protein breakdown.

With regard to the second part of the question, "Can it be of any help?", there was a recent research paper which attempted to answer this question (Effect of leucine metabolite b-hydroxy-b-methylbutyrate on muscle metabolism during resistance exercise training. Journal of Applied Physiology Vol.81(5): 2095-2104, 1996). The purpose of this study was to determine whether giving HMB to subjects engaging in strength training exercise would slow protein breakdown. This study also examined the effects of one group ingesting 175 grams/day of protein versus a group ingesting 117 grams/day. And finally, the investigators conducted a second longer study to determine whether the changes in body composition and strength seen during the first study were evident over a longer period of time.

In study one, 41 male volunteers, 19-29 years of age, were selected, and 32 male volunteers, 19-22 years of age, were selected for study two. The subjects averaged 82.7 + 1.6 kg (about 182 lbs.). The treatment groups were control (n=6) control plus 1.5 g HMB/day (n=6), control plus 3 g HMB/day (n=8), high protein (n=7), high protein plus 1.5 g HMB/day (n=7), and high protein plus 3 g HMB/day (n=7).

The strength training program consisted of both free weights and machines. It worked each muscle group once or twice weekly. The exercises included bench press, lat pulldown, seated rows, pec deck, preacher curls, dumbbell curls, triceps pushdown, seated leg press, calf raises, leg curls, leg extension, sit-ups, inclined leg life, and back extensions. The subjects lifted three times per week with at least one day of rest between sessions. During this three week study, each subject lifted 10 times (5 upper body and 5 lower body). Each exercise included 2 sets of 10 reps at 30 and 60% of the individual's 1 RM as a warm-up, followed by 3 sets of 3-5 reps at 90% of 1 RM. When necessary, weights were adjusted to assure failure on the third to fifth rep.

After each workout, the average weight lifted on the last to sets was increased by 2% and these weights were used as the target weight to be lifted at the next session. Each session was monitored by trained supervisors who recorded weights and judged whether changes in weights were necessary to produce failure after three to five reps.

In this study, muscle strength was assessed by calculating the average weight lifted during the last three working sets of each exercise. The average weight was then multiplied by the number of repetitions the weight was lifted to yield a work index.

The results from the first study, relative to body composition changes, revealed the following: 1) Protein level had no significant effect on body weight change. 2) The loss of fat weight over the 3 week study ranged from 1-1.8 kg and there was not a significant difference among the groups. 3) Lean tissue increased 0.4 kg for the non- HMB group, 0.8 kg for the 1.5 g HMB group, and 1.2 kg for the 3 g HMB group.

The gains in muscle strength revealed that all subjects increased the amount of weight lifted in each exercise and the total number of abdominal efforts during the 3 week training period. No differences in the amount of weight lifted were seen between the normal and high protein groups for any of the exercises. The HMB supplementation did not make a significant difference in upper body strength but it did for lower body strength and total strength [when upper body and lower body were added together]. The nonsupplemented group increased total strength 8% during the 3 week program while the 1.5 g HMB and 3 g HMB group increased total strength 13% and 18.4%, respectively.

To access the inhibition of protein breakdown, the investigators analyzed plasma CK levels, 3-MH loss in the urine, and plasma amino acid levels. HMB supplemented subjects had lower levels of plasma CK, but because of variations among the subjects, it was not significant. HMB had a positive effect of 3-MH levels the first two weeks of the study but not the third week. Plasma concentrations of most amino acids were not significantly changed by either protein intake or HMB supplementation. However, the essential amino acids increased 32% in the nonsupplemented subjects and decreased 9 and 18% in the 1.5 g HMB and 3 g HMB groups, respectively.

In study 2, which lasted seven weeks, all subjects tended to increase body weight and fat weight, and there was no significant beneficial effect of HMB supplementation on these measures. The only difference was the HMB supplemented group tended to increase their fat free mass gains earlier in the study. However, on the last day of the study, fat free mass was not significantly different between the groups.

In the seven week study the nonHMB group increased their bench press from 315 to 321 while the HMB groups increased from 299 to 314, this difference was significant. The nonHMB group increased their squat from 221 to 250. The HMB group increased their squat from 388 to 420 and their hang cleans from 222 to 252. For both the squat and the hang clean, HMB did not have a significant impact.

The authors summarized that dietary supplementation of 3 g of HMB/day for subjects engaging in intense strength training exercise resulted in an increased gain of fat free mass and accompanying increase in strength. Muscle protein breakdown was also decreased with HMB.

I have a different view of how to summarize the information gained from both the three-week and seven-week studies. In terms of body composition changes, if one were to start strength training and supplemented with HMB they may gain more fat free mass in the first three weeks of a seven-week training program than if they did not supplement with HMB. However, total fat free mass gain would possibly be the same at the end of the seven week training program with or without HMB supplementation. The strength gains between the first three-week study and the second seven-week study for the HMB supplemented groups are in somewhat of a conflict. The three-week study did not find much of a difference in upper body strength byt lower body strength between nonsupplemented and HMB supplemented groups. The second seven-week study found just the opposite. I interpret this to mean that HMB may not have as significant effect on strength progression as the advertisements lead one to believe.

According to some literature I have received in the mail, HMB supplementation costs about $35 for a bottle of 120 capsules, of 250 mg HMB. This will last an individual 10 days! How can anyone look an honest, hard working, high school football player [or any hard working individual for that matter] in the face and tell them they need to shell out over $100 a month for a supplement that may not make that much of a difference after three to four weeks? They are better off using the money at a local grocery store. HMB may have more relevance in a hospital setting with trauma patients and if it has any application in sports it may be with bodybuilders undergoing extreme dieting in preparation for a contest. Until more studies are performed, I would not look at HMB as being a miracle maker.

[MCWTRAINER]

HMB for Sports & Fitness

Where is it found?
Small amounts of HMB are present in many foods of animal and plant origin, especially alfalfa and catfish. The amino acid leucine is metabolized into a compound called alpha-ketoisocaproate (KIC), which is then turned into HMB by the body. Dietary supplements of HMB are also available.

Why do athletes use it?*
Some athletes say that HMB

promotes the loss body fat.
helps build muscle.
helps increase strength.
speeds recovery between workouts.
reduces post-workout soreness.
What do the advocates say?*
HMB may assist in accelerating the loss of body fat.

Exercise-induced muscle protein breakdown appears to decrease with HMB supplementation. This, in turn, should speed up recovery from exercise-induced muscle damage.

Enhanced strength and increased muscle mass have been documented in people supplementing with HMB. However, to date, a very limited number of studies have been done. Longitudinal studies to indicate possible long-term use effects of HMB have not been completed.

How much is usually taken by athletes?
Biochemical and animal research shows HMB has a role in protein synthesis and might improve muscle growth and overall body composition as a supplement. However, double-blind human research suggests that HMB may only be effective when combined with an exercise program in people who are not already highly trained athletes. Double-blind trials found no effect of 3 to 6 grams per day HMB on body weight, body fat, or overall body composition in weight-training football players or other trained athletes.1 2 3 4 5 However, one double-blind study found that 3 grams per day HMB increased the amount of body fat lost by 70-year old adults who were participating in a strength-training program for the first time.6 A double-blind study of young men with no strength-training experience reported greater improvements in muscle mass (but not in percentage body fat) when HMB was used in the amount of 17 mg per pound of body weight.7 However, another group of men in the same study given twice as much HMB did not experience any changes in body composition.

Are there any side effects or interactions?
No safety issues have been reported in the limited number of studies currently available.

At the time of writing, there were no well-known drug interactions with HMB.

Resources
See a list of books, periodicals, and other resources for this and related topics.

*Athletes and fitness advocates may claim benefits for HMB based on their personal or professional experience. These are individual opinions and testimonials that may or may not be supported by controlled clinical studies or published scientific articles on HMB. For more complete and detailed information, including references and safety information, see HMB as a nutritional supplement.

References
1. Ransone J, Neighbors K, Lefavi R, Chromiak J. The Effect of beta-hydroxy beta-methylbutyrate on muscular strength and body composition in collegiate football players. J Strength Cond Res 2003;17:34–9.

2. Kreider R, Ferreira M, Wilson M, Almada AL. Effects of calcium beta-HMB supplementation with or without creatine during training on body composition alterations. FASEB J 1997;11:A374 [abstract].

3. Slater G, Jenkins D, Logan P, et al. Beta-hydroxy-beta-methylbutyrate (HMB) supplementation does not affect changes in strength or body composition during resistance training in trained men. Int J Sport Nutr Exerc Metab 2001;11:384–96 [review].

4. Kreider RB, Ferreira M, Wilson M, et al. Effects of calcium beta-hydroxy-beta-methylbutyrate (HMB) supplementation during resistance-training on markers of catabolism, body composition and strength. Int J Sports Med 1999;20:503–9.

5. Slater GJ, Jenkins D. Beta-hydroxy-beta-methylbutyrate (HMB) supplementation and the promotion of muscle growth and strength. Sports Med 2000;30:105–16.

6. Vukovich MD, Stubbs NB, Bohlken RM. Body composition in 70-year-old adults responds to dietary beta-hydroxy-beta-methylbutyrate similarly to that of young adults. J Nutr 2001;131:2049–52.

7. Gallagher PM, Carrithers JA, Godard MP, et al. Beta-hydroxy-beta-methylbutyrate ingestion, Part I: effects on strength and fat free mass. Med Sci Sports Exerc 2000;32:2109–15.

[MCWTRAINER]

LATEST RESEARCH
By Davey Dunn

HOW DOES HMB SUPPLEMENTATION EFFECT BODY COMPOSITION, STRENGTH AND MUSCLE CATABOLISM?
A study done at the University of Memphis examined the effects of HMB (as the calcium salt) supplementation during resistance training (6.9+/-0.7 hr x wk(-1)) on markers of catabolism, body composition and strength in experienced resistance-trained males. Subjects were divided into groups that received fortified carbohydrate/protein powder containing either 0, 3 or 6 g x d(-1) of calcium HMB. The study concluded that that 28 d of HMB supplementation (3 to 6 g x d(-1)) during resistance-training does not reduce catabolism or affect training-induced changes in body composition and strength in experienced resistance-trained males.

COMMENTARY: I have been waiting for some legitimate research to come out on HMB. This study seems to reinforce what a lot of us have already suspected that HMB does very little to aid in muscle growth or prevent muscle breakdown. I have felt for a while that HMB supplements were a rip-off (read the product review on Betagen) and this study just helps reinforce my conclusion.
WHAT CAN WE LEARN FROM THIS STUDY? Do not waste your money on HMB. There are plenty of much less expensive products on the market that yield real results like Creatine. Why spend a small fortune on a product that does not work?

Kreider RB. et al. Effects of calcium beta-hydroxy-beta-methylbutyrate (HMB) supplementation during resistance-training on markers of catabolism, body composition and strength. Int J Sports Med 1999 Nov;20(8):503-9.

[MCWTRAINER]

If anyone has more information feel free to post it...

[DaRk_StAr]

There is some evidence that this innovative nutrient can raise anabolism (the constructive phase of metabolism) and promote recovery in trained athletes. As well, there may be some other beneficial effects for the endurance athlete who chooses to use this novel supplement. HMB stands for beta-hydroxy-beta-methyl butyrate. I think we'll just stick with its acronym. Like so many other sport nutrition supplements, it was the bodybuilding community that first started using HMB in early 1996. However, endurance have since picked up on this supplement, which potentially may be of more benefit to them than the strength athlete or bodybuilder.

HMB is a metabolite of the branched-chain amino acid leucine. Depending on the diet, the can body produce 0.3 to 1 gram of HMB per day in muscle tissue (9). It is found in both plants and animals and is particularly concentrated in alfalfa, corn silage, grapefruit and catfish. Although HMB is found in higher concentrations in these foods, the amounts are still far too small to get a beneficial amount. You would likely have to eat several pounds of this food to get close to the amount needed for a beneficial effect. Some have also questioned whether taking large amounts of leucine, a much cheaper supplement than HMB, can raise HMB levels. It was suggested though that you would have to consume 60 grams of leucine a day to get the body to make 3 grams (the least amount for a beneficial effect) of HMB.

Research has indicated that up to 10% of the amino acid leucine can be oxidized (catabolized) to HMB in muscle and that about 20% of HMB produced is lost in the urine (9). The site(s) of further metabolism is currently unknown. It is thought that most of the HMB produced exits muscle to be used elsewhere in the body, leaving very little for muscle use. When additional HMB is introduced, however, either by infusion or through diet, increased uptake by muscle occurs (up to 30%), indicating that muscle tissue can be a major site of HMB metabolism when concentrations are high.

The increased anabolism that has been found in other studies, through the use of HMB, may be from the reversed flow of HMB travel*maybe there is actually enough HMB in the body for other processes, so any surplus can be used by muscle. Or perhaps, because HMB plasma levels are increased through supplementation, the body does not have to break down its own muscle to liberate leucine for the production of HMB for other metabolic processes.

It has been suggested that HMB is effective at building strength, increasing lean body mass and enhancing recovery because it guards against or slows muscle proteolysis (protein breakdown). In one of the better studies on HMB and exercise (6), 41 healthy males were randomly assigned to receive either 0, 1.5 or 3 grams of HMB per day in orange juice. Diets were meat-free for 3 days each week during which blood and urine were collected. The subjects were weight-trained 3 times per week for three weeks. The group who consumed 3 grams per day of HMB showed a 55% increase (over the control) in lean tissue over the 3 week study.

The changes in lean mass were as follows for each group respectively: The control (0 grams of HMB per day) group showed a 0.4 kg increase in lean mass, the 1.5 gram HMB group showed a 0.8 kg increase in lean mass and the 3 gram HMB group showed a 1.2 kg increase on average. There was also a measured strength increase which appeared to be dose dependent. The researchers measured the muscle/protein breakdown biomarkers creatine phosphokinase (CPK), 3-methylhistidine (3-MH), and lactate dehydrogenase (LDH) to determine HMB¹s effect.

They also looked at nitrogen balance*a measure of protein use and excretion in the body. The major finding of this work was that HMB supplementation resulted in an enhancement of muscle function in humans undergoing resistance exercise. Improvements in muscle strength (295% greater than subjects who didn't use HMB) and increases in lean tissue mass (55% more than the group of non-users) were also found. As well, nitrogen retention improved, a 20% decrease in 3-MH excretion occurred, and a 20-60% decrease in the levels of the enzymes CPK and LDH were also found. Finally, the investigators discovered that there was a greater increase in plasma amino acids in the unsupplemented group compared to the HMB supplemented group. This is significant because blood samples were taken after an overnight fast. This means that food had nothing to do with increased plasma amino acids. Instead, it is likely the amino acids came from muscle breakdown. This data suggests HMB somehow supports the body¹s ability to minimize muscle damage associated with muscular work or stress.

Think what this could do for a road cyclist competing in a stage race. HMB could be very useful for protecting the muscles from the damage of racing, allowing the athlete to recover more completely after each race. Imagine the advantage a cyclist would have in the final stages of a tour. For the same reasons, HMB may be very useful for any endurance athlete during their heavy training periods.

Although it is not known exactly how HMB works, one hypothesis is that HMB helps decrease muscle protein turnover. It has been suggested by some magazine writers that this decrease in muscle damage in turn results in a more rapid neural recruitment by the muscle fibers and may act as a catalyst to faster increases in strength (7). Unfortunately, it was not explained what this meant and how they got this idea. It seems to me like a bit of a stab in the air. Nevertheless, HMB seems promising. In the same study it was also found that the unsupplemented group lost strength in the first week of weight training while the HMB supplemented grouped gained some strength.

More pertinent to endurance athletes, a study performed by researchers at Wichita State University in Kansas found that HMB supplementation increased VO2max in well-trained cyclists by an average of 4% (12). Eight cyclists took either 3 grams of HMB, 3 grams of leucine, or 3 grams of a placebo during a two week period. The results showed the above stated improvement in VO2max, with no effect seen in the leucine or placebo groups. Although the results were not statistically significant, the researchers also found that lactate levels increased in the HMB group, indicating that they were able to work harder, produce more lactate, and tolerate it more. That means an endurance athlete with a VO2max of 70 ml/kg/min could potentially raise his/her VO2max to about 73 ml/kg/min in just two weeks!

That could easily be the difference between first and tenth place in a race. Now, before getting too excited about these results, it is important to understand that it was just one study performed on just 8 subjects, and the research was only presented as an abstract. Published research presented as abstracts are often not scrutinized as carefully as a full journal article would be. Nevertheless, the results are promising. So much so that I recommend its use if you are seeking a nutritional way to boost performance*experiment to see how it works for you.

A study on women was performed to determine if the same results with HMB that have been found in men occurred in women (5). A group of non-exercising women were given either 3 grams of HMB per day or a placebo for 4 weeks. Another group was given the same thing along with an exercise program to perform. The group of women who didn¹t exercise while using HMB had no statistically significant changes in body composition, while the women who both took HMB and exercised experienced lean tissue gains, fat losses, and strength gains similar to those of men.

One of the most recent studies by Vukovich et al. looked at the effects of HMB consumption on body composition in older men and women between the ages of 69 and 71 (11). Over the 8-week period subjects performed resistance exercises 2 times per week while orally consuming 3 grams of HMB per day. The results were quite dramatic. One repetition maximum leg curl strength after 8 weeks increased on average 42.4% as compared to only 18% for the placebo subjects. Lean body mass increased by an average of 1.5 kg for the HMB group while the placebo group's average lean body mass declined by about a half kilogram. Lastly, fat mass declined by 4% in the 8 week period for the HMB users, while it actually increased slightly (0.31%) in the placebo trial. Another recent study by Cheng and colleagues supports these fat loss results by showing increases in fat metabolism in cultured heart and skeletal muscle cells after exposure to HMB (1).

Although HMB is currently not an IOC banned substance, it can easily be tested for by blood and urine samples and the use of gas chromatography and mass spectrometry (2). Because of the invasiveness of blood testing, it's not likely the IOC or any other sport governing body will test for HMB in that manner. However, it has been shown that about half of all HMB, whether it be from dietary sources or produced in the body, is lost in the urine. That means a urine test can probably detect HMB use. This doesn't necessarily have to be a problem for an athlete wishing to boost recovery with HMB and who has a chance of being tested.

[DaRk_StAr]

HMB has been found in various animal species to have a relatively short half-life. The half-life was found to be about 1 hour in rats, 2 hours in pigs, and 3 hours in sheep (4). This suggests that the half-life in humans would probably range between 2 and 4 hours and indicate that HMB would perhaps be undetectable as early as 8 hours after cessation of use.

Knowing that HMB has an approximate half-life of 2-4 hours in humans is important when deciding how to consume this nutrient. Let¹s say you take HMB only in the morning. With a short life span the HMB will decline back to normal levels in just a couple of hours and you will not benefit from its use for the rest of the day. Instead, spread out HMB consumption throughout the day for best results. I think 3-6 grams per day should be used. If your budget is tight then just use 3 grams a day. If you really want a kick in the pants, use 6 grams a day. I suggest that you take some HMB as soon as you awake in the morning, after every workout, with each meal, and finally just before bed. And try to consume food with each HMB intake. Using this strategy, you spread the doses of HMB throughout the day, thereby maximizing its potential effects.

Taking it right before bed and immediately upon waking will ensure that your body doesn't go too long without this nutrient. As well, because one of HMB¹s positive effects is to protect muscle tissue during the stresses of training, it is likely a good idea to load yourself up with the stuff before every workout, especially the hard ones.

[DaRk_StAr]

The patent for HMB use as a sport supplement is owned by Iowa State University Research Foundation (ISURF) and has been licensed to Metabolic Technologies, Inc. under U.S. patent number 5,348,979. If you come across an HMB supplement that doesn't have this patent number on its label, don't buy it. It's very likely fake. This does not mean that an HMB product that doesn't have the patent number on the label is certainly counterfeit. The current patents protect the nutritional uses of HMB for promoting nitrogen retention and the explanation of those methods. These "use" patents do not prevent others from manufacturing HMB, it just prevents them from saying their products improve nitrogen retention and muscle growth. However, because HMB is not a simple nutrient to manufacture, in all likelihood any product that doesn¹t have the patent #5,348,979 is fraudulent.

In terms of safety, a number of animal species have been fed large amounts of HMB for varying periods of time (4). In all the animal studies, there were no adverse effects or increases in death rates. When animals were autopsied, there were no pathological changes in their organs or tissues. Instead, the investigators found a lowered LDL (bad cholesterol) response, increased immune function, fewer respiratory illnesses, more lean body mass, and reduced fat mass. Even when pigs were fed 100 times that used by humans, no problems occurred.

In human studies using 2-5 grams of HMB, blood chemistry, liver function, and kidney function all remained normal. All the human studies that looked at cholesterol found an average LDL decrease of 7% (4).

This brings me to one theory of how HMB may work to increase anabolism. It is thought that HMB converts to cholesterol in muscle cells for use in growth and enhanced function. Although cholesterol has been given a bad rap, it is still a crucial substance in the human body*we would die without it. Since many tissues do not absorb cholesterol from the blood, inadequate production may limit cell and tissue growth, which potentially can be corrected by HMB supplementation. This increase in muscle cholesterol may signal the liver to slow cholesterol production and thereby explain possibly why serum LDL levels decline with HMB use.

Although HMB has been found to be quite safe there is one effect that is somewhat concerning, especially for the endurance athlete. There is some science showing that HMB binds to phosphate (8). This study showed that HMB is as efficient as calcium acetate in binding phosphate in vitro (test tube), and it may be an effective treatment for uremia patients. Uremia is a state of excess urea, creatinine, and other nitrogenous end products of protein and amino acid metabolism, often caused by kidney failure. When the kidneys fail, the filtration rate decreases causing electrolytes like sodium phosphate to accumulate. HMB may help bind to this excess phosphate. Unfortunately, for healthy endurance athletes this is not a good thing. Phosphate is a very important mineral for normal bodily processes and endurance athletes are very dependent on it for optimal performance. In fact, supplementing with sodium phosphate can have potential ergogenic effects.

Some supplement companies have recognized this problem and have added phosphate, usually either as sodium or potassium phosphate, to their preparations. If you do choose to use HMB, carefully check the ingredients on the label to determine whether the product contains additional phosphate. If it doesn't, use another product that does or use a separate phosphate supplement along with the HMB supplement.

References:

1. Cheng, et al., Beta-hydroxy-beta-methyl butyrate increases fatty acid oxidation by muscle cells. FASEB J. 11:A381, 1997.
2. Nissen1, et al., Analysis of ß-Hydroxy-ß-methyl Butyrate in Plasma by Gas Chromatography and Mass Spectrometry. Anal. Biochem. 188:17-19, 1990.
3. Nissen2, et al., Effect of ß-hydroxy-ß-methyl butyrate (HMB) supplementation on strength and body composition of trained and untrained males undergoing intense resistance training. FASEB J. 11:A150 ,1996.
4. Nissen3 and Abumrad, Nutritional role of the leucine metabolite ß-hydroxy ß-methylbutyrate (HMB). J. Nutri. Biochem. 8:300-311, 1997.
5. Nissen4, et al., Effect of feeding ß-hydroxy-ß-methyl butyrate (HMB) on body composition and strength of women. FASEB J. 11:A150, 1997.
6. Nissen5, et al., Effect of leucine metabolite S-hydroxy-ß-methylbutyrate on muscle metabolism during resistance-exercise training. J. Appl. Physiol. 81:2095-2104, 1996.
7. Phillips, HMB. Muscle Media 2000, 47:46-51, 1996.
8. Sousa, Calcium ß-hydroxy-ß-methylbutyrate. Potential role as a phosphate binder in uremia: In vitro study. Nephron 72:391-394, 1996.
9. Talleyrand, et al., Uptake and output of the leucine metabolite ß-hydroxy-ß-methyl butyrate (HMB) across the leg of pigs. FASEB J. 7:A71, 1993.
10. Van Koevering and Nissen, Oxidation of leucine alpha-ketoisocaproate to ß-hydroxy-ß-methylbutyrate in vivo. Am. J. Physiol. 262:E27-E31, 1992.
11. Vuckovich, et al., The effect of dietary ß-hydroxy-ß-methyl butyrate (HMB) on strength gains and body composition changes in older adults. FASEB J. 11:A376, 1997.
12. Vuckovich and Adams, Effect of ß-hydroxy-ß-methyl butyrate (HMB) on VO2 peak and maximal lactate in endurance trained cyclists. Med. Sci. Sports Exerc. 29:S252, 1997.

[Cherokee]

What product does Met-Rx sell that has HMB in it?

peace,
Cherokee

[ReEvolution]

HMB worked nicely for me, but only after i doubled the dose and
spent a damn fortune. not worth the cost, but again it works
well in large doses.

[DaRk_StAr]

HMB worked nicely for me, but only after i doubled the dose and
spent a damn fortune. not worth the cost, but again it works
well in large doses.

how much did you use and how did you take it

[Spud]

Works well for me when calorie deficient @ 10g per day spread out. I get it in bulk from BN @ $68 a kilo. 3+ months supply for $68.......pretty cheap to me.

[MCWTRAINER]

What product does Met-Rx sell that has HMB in it?

peace,
Cherokee

Nothing.

[MCWTRAINER]

Dark Star, thanks for adding some good information to this thread.

[excalibur]

weeew
good thread

[esquire415]

http://www.hmb.org/071a.cfm
http://www.hmb.org/refereed_pub.cfm

Special Research Update: Supplement Article Rates the Highest!
In the last issue of the HMB Newsletter, we highlighted the meta-analysis paper on the effect of nutritional supplements to increase muscle mass and strength gains associated with resistance training. This analysis showed only creatine and HMB significantly increase strength and muscle mass. After the article appeared in the February issue of the Journal of Applied Physiology (Vol. 94; pp. 651-659), it has been the topic of several news articles and has been on top of "The 50 Most-Frequently-Read Contents in Journal of Applied Physiology" for both the months of January and February (to view the list click here). This high ranking is rather unusual and indicates the importance and overall interest of this work.

Key points of this meta-analysis:

This work is not a review. Rather, it is an actual analysis of all of the data from numerous supplement studies. The science is in the numbers and in the statistical analysis … opinion is not a part of the equation.
HMB and creatine are the only supplements that have been shown to "work". With such a substantial body of research on HMB and creatine, there is little chance that additional research will ever contradict these conclusions.
As for the other supplements presented in the meta-analysis, it is unlikely that a series of several positive studies will "statistically" change the outcome, thus these results will likely stand.

Furthermore, there doesn't appear to be any supplements on the horizon that look to join the "elite group" of HMB and creatine. Therefore, HMB and creatine will remain the "proven" supplements for increasing strength and muscle mass.

The results from this meta-analysis reinforce what we have said before about HMB … HMB doubles the effects of exercise and the combination of HMB and creatine is the most powerful supplement you can buy!

The following excerpt is from the summary of the meta-analysis that appeared in the last newsletter.

HMB and Creatine Stand Above the Rest:

Of the 250 supplements examined in this analysis, only six had two or more studies that met the criteria for inclusion. The following table is a breakdown of how the results would equate to a 200 lbs person with a 200 lbs one-repetition maximum bench press over 6 weeks of supplementation. As you can see from the table, only creatine and HMB significantly increase strength and muscle mass. It was expected that creatine would probably be the best supplement for increasing muscle mass. However, HMB was found to be the best supplement for increasing strength and second only to creatine in increasing muscle mass.



Creatine and HMB: The Power Team
http://www.creatinemonohydrate.net/c...letter_25.html

Killer Combos for Mass
http://www.findarticles.com/p/articl..._98432744/pg_1

[esquire415]

http://www.hmb.org/055.cfm

Simply the Best --- One of the most popular supplements on the market is the combination of HMB and Creatine. Research shows this combination is simply the best product to increase muscle mass and strength! Currently there are two great products, EAS's Betagen and Met-Rx's Mass Action, that combine these two proven supplements.

Research Update
The following study was presented at the American College of Sports Medicine Meeting in Baltimore, May 30 - June 2, 2001.

Effects of HMB Supplementation on LDL-Cholesterol, Strength and Body Composition of Patients with Hypercholesterolemia. C. Coelho and T. Carvalho. (2001) Med. Sci. Sports Exer. Abstract #1912: 33(5): S340.

Twelve males (ages 50 - 72 years) with total cholesterol: HDL cholesterol ratios greater than 4.5 were randomly assigned to either 3 grams HMB or 3 grams placebo daily for 4-weeks. The results showed a 28% decrease in LDL cholesterol and a 6% increase in lean mass in the HMB group with no change in the placebo group. Significant increases in strength occurred in the HMB group as well.

Conclusion: If you have high cholesterol (in the range that should be treated), HMB and exercise may be something you might try to help lower blood cholesterol. Keep in mind, findings from this study showed that HMB again promotes muscular strength and lean mass.

Frequently Asked Questions
Q. What is the recommended dosage of HMB (for me)?

A. The current recommended dosage is three (3) grams of HMB per day for the average sized individual. However, research has shown that there is an optimal dosage that you should use to 'customize' your dosage, and this is 38 mg of HMB per Kg (or 17 mg of HMB per lb) of body weight each day. See table below for a dosage/weight chart:

HMB Dosage Chart
------------------
Body
Weight__HMB
(lbs)____(grams/day)
100....... 1.50
125....... 2.00
150....... 2.50
175....... 3.00
200....... 3.50
225....... 4.00
225....... 4.25
275....... 4.75