Β-Hydroxy β-methylbutyric acid: Difference between revisions
Content deleted Content added
| Line 52: | Line 52: | ||
}} |
}} |
||
'''β-Hydroxy β-methylbutyric acid''' ('''HMB''') and its [[conjugate base]] '''β-hydroxy β-methylbutyrate''' ('''hydroxymethylbutyrate''', '''HMB''') are [[nutritional supplement]]s |
'''β-Hydroxy β-methylbutyric acid''' ('''HMB''') and its [[conjugate base]] '''β-hydroxy β-methylbutyrate''' ('''hydroxymethylbutyrate''', '''HMB''') are [[nutritional supplement]]s that generally aid in promoting [[muscle hypertrophy|skeletal muscle growth]] and decreasing exercise-induced muscle damage.<ref name="Review Feb 2013">{{cite journal | vauthors = Wilson JM, Fitschen PJ, Campbell B, Wilson GJ, Zanchi N, Taylor L, Wilborn C, Kalman DS, Stout JR, Hoffman JR, Ziegenfuss TN, Lopez HL, Kreider RB, Smith-Ryan AE, Antonio J | title = International Society of Sports Nutrition Position Stand: beta-hydroxy-beta-methylbutyrate (HMB) | journal = J. Int. Soc. Sports. Nutr. | volume = 10 | issue = 1 | pages = 6 | date = February 2013 | pmid = 23374455 | pmc = 3568064 | doi = 10.1186/1550-2783-10-6 | quote = The International Society of Sports Nutrition (ISSN) bases the following position stand on a critical analysis of the literature on the use of beta-hydroxy-beta-methylbutyrate (HMB) as a nutritional supplement. The ISSN has concluded the following. 1. HMB can be used to enhance recovery by attenuating exercise induced skeletal muscle damage in trained and untrained populations. 2. If consuming HMB, an athlete will benefit from consuming the supplement in close proximity to their workout. 3. HMB appears to be most effective when consumed for 2 weeks prior to an exercise bout. 4. Thirty-eight mg·kg·BM-1 daily of HMB has been demonstrated to enhance skeletal muscle hypertrophy, strength, and power in untrained and trained populations when the appropriate exercise prescription is utilized. 5. Currently, two forms of HMB have been used: Calcium HMB (HMB-Ca) and a free acid form of HMB (HMB-FA). HMB-FA may increase plasma absorption and retention of HMB to a greater extent than HMB-CA. However, research with HMB-FA is in its infancy, and there is not enough research to support whether one form is superior. 6. HMB has been demonstrated to increase LBM and functionality in elderly, sedentary populations. 7. HMB ingestion in conjunction with a structured exercise program may result in greater declines in fat mass (FM). 8. HMB’s mechanisms of action include an inhibition and increase of proteolysis and protein synthesis, respectively. 9. Chronic consumption of HMB is safe in both young and old populations. }}</ref><ref name="Review July 2010">{{cite journal | vauthors = Portal S, Eliakim A, Nemet D, Halevy O, Zadik Z | title = Effect of HMB supplementation on body composition, fitness, hormonal profile and muscle damage indices | journal = J. Pediatr. Endocrinol. Metab. | volume = 23 | issue = 7 | pages = 641–50 | date = July 2010 | pmid = 20857835 | doi = | quote = There is a huge market for ergogenic supplements for athletes. However, only a few products have been proven to have ergogenic effects and to be effective at improving muscle strength and body composition. One such supplement is beta-hydroxy beta-methylbutyrate (HMB). ... Several studies have shown that combining exercise training with HMB supplementation leads to increased muscle mass and strength, and there is some anecdotal evidence of aerobic improvement. However, HMB supplementation has been found to be effective mainly for untrained individuals. While previous reviews have emphasized three main pathways for HMB's mode of action: 1) enhancement of sarcolemmal integrity via cytosolic cholesterol, 2) inhibition of protein degradation via proteasomes, and 3) increased protein synthesis via the mTOR pathway, more recent studies have suggested additional possible mechanisms for its physiological effects. These include decreased cell apoptosis and enhanced cell survival, increased proliferation, differentiation and fusion via the MAPK/ERK and PI3K/Akt pathways, and enhanced IGF-I transcription}}</ref><ref name="Systematic review December 2013" /> |
||
HMB is a [[leucine]] metabolite produced in the body through oxidation of the [[ketoacid]] of leucine ([[alpha-Ketoisocaproic acid|α-ketoisocaproate]]).<ref name="Review Feb 2013" /> It is found in various foods including [[grapefruit]] and [[catfish]] and is sold as a [[dietary supplement]], sometimes as the calcium [[salt (chemistry)|salt]], ''calcium hydroxymethylbutyrate''.<ref name="Review Feb 2013" /><ref name=2008rev>{{cite journal |author=Wilson GJ, Wilson JM, Manninen AH. |title=Effects of beta-hydroxy-beta-methylbutyrate (HMB) on exercise performance and body composition across varying levels of age, sex, and training experience: A review. |journal=Nutrition & Metabolism |year=2008 |pmid=18173841 |doi=10.1186/1743-7075-5-1 |volume=5 |pages=1 |pmc=2245953 | quote = HMB is a metabolite of leucine, and can be consumed through both plant and animal foods such as grapefruit and catfish, it has been credited as a dietary supplement [21-23].}}</ref> There appear to be no issues with safety (i.e., no [[adverse effects]]) from long-term use as a nutritional supplement in young or old individuals.<ref name="Review Feb 2013" /><ref name="Systematic review December 2013">{{cite journal | vauthors = Molfino A, Gioia G, Rossi Fanelli F, Muscaritoli M | title = Beta-hydroxy-beta-methylbutyrate supplementation in health and disease: a systematic review of randomized trials | journal = Amino Acids | volume = 45 | issue = 6 | pages = 1273–1292 | date = December 2013 | pmid = 24057808 | doi = 10.1007/s00726-013-1592-z | quote = Beta-hydroxy-beta-methylbutyrate (HMB), a metabolite of the branched-chain amino acid leucine, is extensively used by athletes and bodybuilders in order to increase strength, muscle mass and exercise performance. ... The indexed studies support that HMB is effective in preventing exercise-related muscle damage in healthy trained and untrained individuals as well as muscle loss during chronic diseases. Most of the selected studies showed the effectiveness of HMB in preventing exercise-related muscle damage in healthy trained and untrained individuals as well as muscle loss during chronic diseases. The usual dose of 3 g/day may be routinely recommended to maintain or improve muscle mass and function in health and disease. The safety profile of HMB is unequivocal. Further, well-designed clinical studies are needed to confirm effectiveness and mode of action of HMB, particularly in pathological conditions.}}</ref><ref name="PEDs in sports review">{{cite journal | vauthors = Momaya A, Fawal M, Estes R | title = Performance-enhancing substances in sports: a review of the literature | journal = Sports Med. | volume = 45 | issue = 4 | pages = 517–531 | date = April 2015 | pmid = 25663250 | doi = 10.1007/s40279-015-0308-9 | quote = <br />3.6 Beta-Hydroxy-Beta-Methylbutyrate<br />HMB is a metabolite of the amino acid leucine and is a precursor to cholesterol. ... A 2013 NCAA survey study reported a 0.2 % rate of use among all student athletes [13]. However, it appears that HMB is increasingly being added to many training regimens [88]. ... There are several proposed mechanisms by which HMB acts. One of the primary mechanisms involves the up-regulation of the mechanistic target of rapamycin/ p70S6K signaling pathway, which promotes protein synthesis and muscle hypertrophy [89].<br />Other studies have focused on the anti-catabolic effects of HMB. Smith et al. [90] demonstrated that HMB preserved lean body mass and decreased proteolysis through the down-regulation of the increased expression of certain components of the ubiquitin–proteasome proteolytic pathway. Some studies have examined HMB and its effect on muscle by measuring markers of muscle breakdown. Wilson et al. [91] demonstrated that when non-resistancetrained males received HMB pre-exercise, the rise of lactate dehydrogenase (LDH) levels reduced, and HMB tended to decrease soreness. Knitter et al. [92] showed a decrease in LDH and creatine phosphokinase (CPK), a byproduct of muscle breakdown, by HMB after a prolonged run. ... Despite differences in these studies, it does appear that HMB overall enhances muscular hypertrophy, strength, and power. In fact, the International Society for Sports Nutrition, in a position statement, writes that HMB can be used to enhance recovery by reducing skeletal muscle damage after exercise in athletically trained and untrained people. The utility of HMB does seem to be affected by timing of intake prior to workouts and dosage [97]. Further, chronic consumption of HMB appears safe [97]. ... Currently, HMB is available as an over-the-counter supplement. The drug is not tested for nor banned by any sporting organization.}}</ref> |
|||
HMB is a [[leucine]] metabolite produced in the body through oxidation of the [[ketoacid]] of leucine ([[alpha-Ketoisocaproic acid|α-ketoisocaproate]]).<ref name="Review Feb 2013" /> It is sold as a [[dietary supplement]], sometimes as the calcium [[salt (chemistry)|salt]], ''calcium hydroxymethylbutyrate''.<ref name="Review Feb 2013" /><ref name=2008rev>{{cite journal |author=Wilson GJ, Wilson JM, Manninen AH. |title=Effects of beta-hydroxy-beta-methylbutyrate (HMB) on exercise performance and body composition across varying levels of age, sex, and training experience: A review. |journal=Nutrition & Metabolism |year=2008 |pmid=18173841 |doi=10.1186/1743-7075-5-1 |volume=5 |pages=1 |pmc=2245953}}</ref> |
|||
== References == |
== References == |
||
Revision as of 20:28, 30 April 2016
 | This article is missing information about Error: you must specify what information is missing.. (April 2016) |
| |
| |
| Names | |
|---|---|
| IUPAC name
3-hydroxy-3-methylbutanoic acid
| |
| Other names
β-Hydroxyisovaleric acid
3-Hydroxyisovaleric acid | |
| Identifiers | |
3D model (JSmol)
|
|
| Abbreviations | HMB |
| ChEBI | |
| ChemSpider | |
| ECHA InfoCard | 100.128.078 |
PubChem CID
|
|
| UNII | |
CompTox Dashboard (EPA)
|
|
| |
| |
| Properties | |
| C5H10O3 | |
| Molar mass | 118.131 g/mol |
| Density | 0.938 g/mL |
| Melting point | −80 °C (−112 °F; 193 K) |
| Boiling point | 88 °C (190 °F; 361 K) at 1 mmHg |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
| |
β-Hydroxy β-methylbutyric acid (HMB) and its conjugate base β-hydroxy β-methylbutyrate (hydroxymethylbutyrate, HMB) are nutritional supplements that generally aid in promoting skeletal muscle growth and decreasing exercise-induced muscle damage.[1][2][3]
HMB is a leucine metabolite produced in the body through oxidation of the ketoacid of leucine (α-ketoisocaproate).[1] It is found in various foods including grapefruit and catfish and is sold as a dietary supplement, sometimes as the calcium salt, calcium hydroxymethylbutyrate.[1][4] There appear to be no issues with safety (i.e., no adverse effects) from long-term use as a nutritional supplement in young or old individuals.[1][3][5]
References
- ^ a b c d Wilson JM, Fitschen PJ, Campbell B, Wilson GJ, Zanchi N, Taylor L, Wilborn C, Kalman DS, Stout JR, Hoffman JR, Ziegenfuss TN, Lopez HL, Kreider RB, Smith-Ryan AE, Antonio J (February 2013). "International Society of Sports Nutrition Position Stand: beta-hydroxy-beta-methylbutyrate (HMB)". J. Int. Soc. Sports. Nutr. 10 (1): 6. doi:10.1186/1550-2783-10-6. PMC 3568064. PMID 23374455.
The International Society of Sports Nutrition (ISSN) bases the following position stand on a critical analysis of the literature on the use of beta-hydroxy-beta-methylbutyrate (HMB) as a nutritional supplement. The ISSN has concluded the following. 1. HMB can be used to enhance recovery by attenuating exercise induced skeletal muscle damage in trained and untrained populations. 2. If consuming HMB, an athlete will benefit from consuming the supplement in close proximity to their workout. 3. HMB appears to be most effective when consumed for 2 weeks prior to an exercise bout. 4. Thirty-eight mg·kg·BM-1 daily of HMB has been demonstrated to enhance skeletal muscle hypertrophy, strength, and power in untrained and trained populations when the appropriate exercise prescription is utilized. 5. Currently, two forms of HMB have been used: Calcium HMB (HMB-Ca) and a free acid form of HMB (HMB-FA). HMB-FA may increase plasma absorption and retention of HMB to a greater extent than HMB-CA. However, research with HMB-FA is in its infancy, and there is not enough research to support whether one form is superior. 6. HMB has been demonstrated to increase LBM and functionality in elderly, sedentary populations. 7. HMB ingestion in conjunction with a structured exercise program may result in greater declines in fat mass (FM). 8. HMB's mechanisms of action include an inhibition and increase of proteolysis and protein synthesis, respectively. 9. Chronic consumption of HMB is safe in both young and old populations.
{{cite journal}}: CS1 maint: unflagged free DOI (link) - ^ Portal S, Eliakim A, Nemet D, Halevy O, Zadik Z (July 2010). "Effect of HMB supplementation on body composition, fitness, hormonal profile and muscle damage indices". J. Pediatr. Endocrinol. Metab. 23 (7): 641–50. PMID 20857835.
There is a huge market for ergogenic supplements for athletes. However, only a few products have been proven to have ergogenic effects and to be effective at improving muscle strength and body composition. One such supplement is beta-hydroxy beta-methylbutyrate (HMB). ... Several studies have shown that combining exercise training with HMB supplementation leads to increased muscle mass and strength, and there is some anecdotal evidence of aerobic improvement. However, HMB supplementation has been found to be effective mainly for untrained individuals. While previous reviews have emphasized three main pathways for HMB's mode of action: 1) enhancement of sarcolemmal integrity via cytosolic cholesterol, 2) inhibition of protein degradation via proteasomes, and 3) increased protein synthesis via the mTOR pathway, more recent studies have suggested additional possible mechanisms for its physiological effects. These include decreased cell apoptosis and enhanced cell survival, increased proliferation, differentiation and fusion via the MAPK/ERK and PI3K/Akt pathways, and enhanced IGF-I transcription
- ^ a b Molfino A, Gioia G, Rossi Fanelli F, Muscaritoli M (December 2013). "Beta-hydroxy-beta-methylbutyrate supplementation in health and disease: a systematic review of randomized trials". Amino Acids. 45 (6): 1273–1292. doi:10.1007/s00726-013-1592-z. PMID 24057808.
Beta-hydroxy-beta-methylbutyrate (HMB), a metabolite of the branched-chain amino acid leucine, is extensively used by athletes and bodybuilders in order to increase strength, muscle mass and exercise performance. ... The indexed studies support that HMB is effective in preventing exercise-related muscle damage in healthy trained and untrained individuals as well as muscle loss during chronic diseases. Most of the selected studies showed the effectiveness of HMB in preventing exercise-related muscle damage in healthy trained and untrained individuals as well as muscle loss during chronic diseases. The usual dose of 3 g/day may be routinely recommended to maintain or improve muscle mass and function in health and disease. The safety profile of HMB is unequivocal. Further, well-designed clinical studies are needed to confirm effectiveness and mode of action of HMB, particularly in pathological conditions.
- ^ Wilson GJ, Wilson JM, Manninen AH. (2008). "Effects of beta-hydroxy-beta-methylbutyrate (HMB) on exercise performance and body composition across varying levels of age, sex, and training experience: A review". Nutrition & Metabolism. 5: 1. doi:10.1186/1743-7075-5-1. PMC 2245953. PMID 18173841.
HMB is a metabolite of leucine, and can be consumed through both plant and animal foods such as grapefruit and catfish, it has been credited as a dietary supplement [21-23].
{{cite journal}}: CS1 maint: multiple names: authors list (link) CS1 maint: unflagged free DOI (link) - ^ Momaya A, Fawal M, Estes R (April 2015). "Performance-enhancing substances in sports: a review of the literature". Sports Med. 45 (4): 517–531. doi:10.1007/s40279-015-0308-9. PMID 25663250.
3.6 Beta-Hydroxy-Beta-Methylbutyrate
HMB is a metabolite of the amino acid leucine and is a precursor to cholesterol. ... A 2013 NCAA survey study reported a 0.2 % rate of use among all student athletes [13]. However, it appears that HMB is increasingly being added to many training regimens [88]. ... There are several proposed mechanisms by which HMB acts. One of the primary mechanisms involves the up-regulation of the mechanistic target of rapamycin/ p70S6K signaling pathway, which promotes protein synthesis and muscle hypertrophy [89].
Other studies have focused on the anti-catabolic effects of HMB. Smith et al. [90] demonstrated that HMB preserved lean body mass and decreased proteolysis through the down-regulation of the increased expression of certain components of the ubiquitin–proteasome proteolytic pathway. Some studies have examined HMB and its effect on muscle by measuring markers of muscle breakdown. Wilson et al. [91] demonstrated that when non-resistancetrained males received HMB pre-exercise, the rise of lactate dehydrogenase (LDH) levels reduced, and HMB tended to decrease soreness. Knitter et al. [92] showed a decrease in LDH and creatine phosphokinase (CPK), a byproduct of muscle breakdown, by HMB after a prolonged run. ... Despite differences in these studies, it does appear that HMB overall enhances muscular hypertrophy, strength, and power. In fact, the International Society for Sports Nutrition, in a position statement, writes that HMB can be used to enhance recovery by reducing skeletal muscle damage after exercise in athletically trained and untrained people. The utility of HMB does seem to be affected by timing of intake prior to workouts and dosage [97]. Further, chronic consumption of HMB appears safe [97]. ... Currently, HMB is available as an over-the-counter supplement. The drug is not tested for nor banned by any sporting organization.
Wikimedia Commons has media related to Beta-Hydroxy beta-methylbutyrate.