HMB studier

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Ok først kommer det noen negative studier (4) og tilslutt noen positive studier (9)

Effects of beta-hydroxy-beta-methylbutyrate and creatine monohydrate supplementation on the aerobic and anaerobic capacity of highly trained athletes.

J Sports Med Phys Fitness 2003 Mar;43(1):64-8

O'connor DM, Crowe MJ.

Institute of Sport and Exercise Science, James Cook University, Australia.

AIM: The aim of this study was to investigate the effects of 6 wks oral supplementation of beta-hydroxy-beta-methylbutyrate (HMB) and a mixture of HMB and creatine monohydrate (HMBCr) on aerobic and anaerobic capacity in highly trained athletes. It was hypothesised that HMB and HMBCr would have positive effects on aerobic and anaerobic power. METHODS: A prospective study involving a repeated measures design was utilised where subjects underwent testing prior to, and immediately after, a 6 wks supplementation period. Elite, male rugby league players (n=27) were divided into 3 groups, a control group (n=6), a HMB group (3 g/d; n=10) and a HMBCr group (3 g/d HMB + 3 g/d Cr; n=11). Testing involved a multistage fitness test to determine aerobic power and a 60 sec maximal cycle test to determine anaerobic capacity. Peak power, total work and peak lactate levels were measured in the anaerobic cycle test. RESULTS: Two-way repeated measures ANOVA revealed no effect of HMB or HMBCr on any of the measured parameters in comparison to the control group. CONCLUSION: Aerobic and anaerobic ability of highly trained male athletes is unaffected by 6 wks oral supplementation with HMB or a combination of HMB and creatine monohydrate.

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The Effect of beta-hydroxy beta-methylbutyrate on muscular strength and body composition in collegiate football players.

J Strength Cond Res 2003 Feb;17(1):34-9

Ransone J, Neighbors K, Lefavi R, Chromiak J.

College of Education, Oklahoma State University, Stillwater, Oklahoma 74078, USA. ransone@okstate.edu

This study assesses the effects of daily beta-hydroxy beta-methylbutyrate (HMB) supplementation on muscular strength (bench press, squats, and power cleans) and body composition (body weight and body fat) among collegiate football players undergoing a strenuous exercise program. Subjects were collegiate football players (n = 35) training under the supervision of certified strength coaches averaging 20 hours of weekly exercise. In the first supplementation period, 16 of the 35 subjects were supplemented with 3 g of HMB per day for 4 weeks; the other 19 received a placebo followed by a 1-week washout period and then a second supplementation period in a randomized double-blind crossover, placebo design. There were no significant changes (p > 0.05) in muscular strength, including bench press, squats, and power cleans, among the subjects. There were also no significant changes (p > 0.05) in body composition, including body fat and body weight. Very little clinical evidence exists for supplementing HMB in athletic populations.

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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 Sep;11(3):384-96

Slater G, Jenkins D, Logan P, Lee H, Vukovich M, Rathmacher JA, Hahn AG.

Sports Medicine Sports Science Division of the Singapore Sports Council, National Stadium, Singapore.

This investigation evaluated the effects of oral beta-hydroxy-beta-methylbutyrate (HMB) supplementation on training responses in resistance-trained male athletes who were randomly administered HMB in standard encapsulation (SH), HMB in time release capsule (TRH), or placebo (P) in a double-blind fashion. Subjects ingested 3 g x day(-1) of HMB or placebo for 6 weeks. Tests were conducted pre-supplementation and following 3 and 6 weeks of supplementation. The testing battery assessed body mass, body composition (using dual energy x-ray absorptiometry), and 3-repetition maximum isoinertial strength, plus biochemical parameters, including markers of muscle damage and muscle protein turnover. While the training and dietary intervention of the investigation resulted in significant strength gains (p < .001) and an increase in total lean mass (p = .01), HMB administration had no influence on these variables. Likewise, biochemical markers of muscle protein turnover and muscle damage were also unaffected by HMB supplementation. The data indicate that 6 weeks of HMB supplementation in either SH or TRH form does not influence changes in strength and body composition in response to resistance training in strength-trained athletes.

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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

Kreider RB, Ferreira M, Wilson M, Almada AL.

Department of Human Movement Sciences & Education, The University of Memphis, TN 38152, USA. kreider.richard@coe.memphis.edu

Calcium beta-hydroxy-beta-methylbutyrate (HMB) supplementation has been reported to reduce muscle catabolism and promote gains in fat-free mass and strength in subjects initiating training. However, whether HMB supplementation promotes these adaptations in trained athletes is less clear. This study 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. In a double-blind and randomized manner, 40 experienced resistance-trained athletes were matched and assigned to supplement their diet for 28 d with a fortified carbohydrate/protein powder containing either 0, 3 or 6 g x d(-1) of calcium HMB. Fasting venous blood and urine samples, dual energy X-ray absorptiometer-determined body composition, and isotonic bench press and leg press one repetition maximums (1 RM) were determined prior to and following 28 d of supplementation. HMB supplementation resulted in significant increases in serum and urinary HMB concentrations. However, no statistically significant differences were observed in general markers of whole body anabolic/catabolic status, muscle and liver enzyme efflux, fat/bone-free mass, fat mass, percent body fat, or 1 RM strength. Results indicate 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.

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Ok det var de som viste ingen effekt av HMB nå over til de som viser effekt.[/b]



Effect of beta-hydroxy beta-methylbutyrate on the onset of blood lactate accumulation and V(O)(2) peak in endurance-trained cyclists.

J Strength Cond Res 2001 Nov;15(4):491-7

Vukovich MD, Dreifort GD.

Human Performance Laboratory, Wichita State University, Wichita, Kansas 67260, USA.

The purpose of this study was to determine the effect of beta-hydroxy beta-methylbutyrate (HMB) supplementation on maximal oxygen consumption (.V(O)(2)peak) and the onset of blood lactate accumulation (OBLA) in endurance-trained cyclists. Eight cyclists randomly (double blind) completed 3 2-week supplementation periods (HMB, 3g.day(-1); leucine [LEU], 3g.day(-1); placebo [CON], 3g.day(-1)) followed by a 2-week washout period. Testing consisted of a graded cycle ergometry test to measure .V(O)(2)peak and OBLA, the .V(O)(2) at 2 mM blood lactate. .V(O)(2)peak was unaffected by HMB (4.0 +/- 1.4%), LEU (-1.9 +/- 1.3%), and CON (-2.6 +/- 2.6%). HMB resulted in a greater time to reach .V(O)(2)peak, whereas LEU and CON did not affect this time (HMB, 3.6 +/- 1.5 min, LEU, -1.2 +/- 1.5 min; CON, -3.6 +/- 3.5 min). Lactate accumulation peak was unaffected by supplementation (HMB, 8.1 +/- 1.1 mM; LEU, 6.2 +/- 0.8 mM; CON, 7.5 +/- 1.3 mM). OBLA increased with HMB (9.1 +/- 2.4%) and LEU (2.1 +/- 1.5%), but not in the CON trial (0.75 +/- 2.1%). Blood glucose was significantly greater during the HMB trial compared with the LEU trial. It is concluded that HMB supplementation may have positive affects on performance by increasing the onset of blood lactate accumulation; however, the mechanism is unknown

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Creatine and beta-hydroxy-beta-methylbutyrate (HMB) additively increase lean body mass and muscle strength during a weight-training program.

Nutrition 2001 Jul-Aug;17(7-8):558-66

Jowko E, Ostaszewski P, Jank M, Sacharuk J, Zieniewicz A, Wilczak J, Nissen S.

Institute of Sport and Physical Education, Biala Podlaska, Academy of Physical Education, Warsaw, Poland.

We investigated whether creatine (CR) and beta-hydroxy-beta-methylbutyrate (HMB) act by similar or different mechanisms to increase lean body mass (LBM) and strength in humans undergoing progressive resistance-exercise training. In this double-blind, 3-wk study, subjects (n = 40) were randomized to placebo (PL; n = 10), CR (20.0 g of CR/d for 7 d followed by 10.0 g of CR/d for 14 d; n = 11), HMB (3.0 g of HMB/d; n = 9), or CR-and-HMB (CR/HMB; n = 10) treatment groups. Over 3 wk, all subjects gained LBM, which was assessed by bioelectrical impedance analysis. The CR, HMB and CR/HMB groups gained 0.92, 0.39, and 1.54 kg of LBM, respectively, over the placebo group, with a significant effect with CR supplementation (main effect P = 0.05) and a trend with HMB supplementation (main effect P = 0.08). These effects were additive because there was no interaction between CR and HMB (CR x HMB main effect P = 0.73). Across all exercises, HMB, CR, and CR/HMB supplementation caused accumulative strength increases of 37.5, 39.1, and 51.9 kg, respectively, above the placebo group. The exercise-induced rise in serum creatine phosphokinase was markedly suppressed with HMB supplementation (main effect P = 0.01). However, CR supplementation antagonized the HMB effects on serum creatine phosphokinase (CR x HMB interactive effect P = 0.04). Urine urea nitrogen and plasma urea were not affected by CR supplementation, but both decreased with HMB supplementation (HMB effect P < 0.05), suggesting a nitrogen-sparing effect. In summary, CR and HMB can increase LBM and strength, and the effects are additive. Although not definitive, these results suggest that CR and HMB act by different mechanisms

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Body composition in 70-year-old adults responds to dietary beta-hydroxy-beta-methylbutyrate similarly to that of young adults.

J Nutr 2001 Jul;131(7):2049-52

Vukovich MD, Stubbs NB, Bohlken RM.

South Dakota State University, Brookings, SD 57007, USA. matthew_vukovich@sdstate.edu

Studies in young adults have demonstrated that beta-hydroxy-beta-methylbutyrate (HMB) can increase gains in strength and fat-free mass during a progressive resistance-training program. The purpose of this study was to determine whether HMB would similarly benefit 70-y-old adults undergoing a 5 d/wk exercise program. Thirty-one men (n = 15) and women (n = 16) (70 +/- 1 y) were randomly assigned in a double-blind study to receive either capsules containing a placebo or Ca-HMB (3 g/d) for the 8-wk study. Skin fold estimations of body composition as well as computerized tomography (CT) and dual X-ray absorptiometry (DXA) scans were measured before the study and immediately after the 8-wk training program. HMB supplementation tended to increase fat-free mass gain (HMB, 0.8 +/- 0.4 kg; placebo, -0.2 +/- 0.3 kg; treatment x time, P = 0.08). Furthermore, HMB supplementation increased the percentage of body fat loss (skin fold: HMB, -0.66 +/- 0.23%; placebo, -0.03 +/- 0.21%; P = 0.05) compared with the placebo group. CT scans also indicated a greater decrease in the percentage of body fat with HMB supplementation (P < 0.05). In conclusion, changes in body composition can be accomplished in 70-y-old adults participating in a strength training program, as previously demonstrated in young adults, when HMB is supplemented daily.

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Beta-hydroxy-beta-methylbutyrate ingestion, Part I: effects on strength and fat free mass.

Med Sci Sports Exerc 2000 Dec;32(12):2109-15

Gallagher PM, Carrithers JA, Godard MP, Schulze KE, Trappe SW.

Human Performance Laboratory, Ball State University, Muncie, IN 47306, USA.

PURPOSE: The purpose of this investigation was 1) to determine whether HMB supplementation results in an increase in strength and FFM during 8 wk of resistance training and 2) determine whether a higher dose of HMB provides additional benefits. METHODS: Thirty-seven, untrained, college-aged men were assigned to one of three groups: 0, 38, or 76 mg x kg(-1) x d(-1) of HMB (approximately equal to 3 and 6 g x d(-1), respectively). Resistance training consisted of 10 different exercises performed 3 d x wk(-1) for 8 wk at 80% of 1-repetition maximum (1RM). The 1RM was reevaluated every 2 wk with workloads adjusted accordingly. RESULTS: No differences were observed in 1RM strength among the groups at any time. However, the 38 mg x kg (-1) x d(-1) group showed a greater increase in peak isometric torque than the 0 or 76 mg.kg(-1) x d(-1) groups (P < 0.05). The 76 mg x kg(-1) x d(-1) group had a greater increase in peak isokinetic torque than the 0 or 38 mg x kg(-1) x d(-1) groups at 2.1, -3.15, and -4.2 rad x s(-1) (P < 0.05). Plasma creatine phosphokinase (CPK) activity was greater for the 0 mg x kg(-1) x d(-1) versus the 38 or 76 mg x kg(-1) x d(-1) groups at 48 h after the initial training bout (P < 0.05). In addition, no differences were observed in body fat between the three groups. However, the 38 mg x kg(-1) x d(-1) group exhibited a greater increase in FFM (P < 0.05). CONCLUSIONS: Although the IRM strength gains were not significantly different, HMB supplementation appears to increase peak isometric and various isokinetic torque values, and increase FFM and decrease plasma CPK activity. Lastly, it appears that higher doses of HMB (i.e., > 38 mg x kg(-1) x d(-1)) do not promote strength or FFM gains.

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Effects of beta-hydroxy-beta-methylbutyrate on muscle damage after a prolonged run.

J Appl Physiol 2000 Oct;89(4):1340-4

Knitter AE, Panton L, Rathmacher JA, Petersen A, Sharp R.

Human Performance Laboratory, Iowa State University, Ames, Iowa 50011, USA.

This study examined the effects of supplemental beta-hydroxy-beta-methylbutyrate (HMB) on muscle damage as a result of intense endurance exercise. Subjects (n = 13) were paired according to their 2-mile run times and past running experience. Each pair was randomly assigned a treatment of either HMB (3 g/day) or a placebo. After 6 wk of daily training and supplementation, all subjects participated in a prolonged run (20-km course). Creatine phosphokinase and lactate dehydrogenase (LDH) activities were measured before and after a prolonged run to assess muscle damage. The placebo-supplemented group exhibited a significantly greater (treatment main effect, P = 0.05) increase in creatine phosphokinase activity after a prolonged run than did the HMB-supplemented group. In addition, LDH activity was significantly lower (treatment main effect, P = 0.003) with HMB supplementation compared with the placebo-supplemented group. In conclusion, supplementation with 3.0 g of HMB results in a decreased creatine phosphokinase and LDH response after a prolonged run. These findings support the hypothesis that HMB supplementation helps prevent exercise-induced muscle damage.

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Nutritional supplementation of the leucine metabolite beta-hydroxy-beta-methylbutyrate (hmb) during resistance training.

Nutrition 2000 Sep;16(9):734-9

Panton LB, Rathmacher JA, Baier S, Nissen S.

Department of Education, East Tennessee State University, Johnson City, Tennessee 37614, USA. panton@etsu-tn.edu

The effects of supplementation of the leucine metabolite beta-hydroxy-beta-methylbutyrate (HMB) were examined in a resistance training study. Thirty-nine men and 36 women between the ages of 20-40 y were randomized to either a placebo (P) supplemented or HMB supplemented (3.0 g HMB/d) group in two gender cohorts. All subjects trained three times per week for 4 wk. In the HMB group, plasma creatine phosphokinase levels tended to be suppressed compared to the placebo group following the 4 wk of resistance training (HMB:174. 4 +/- 26.8 to 173.5 +/- 17.0 U/L; P:155.0 +/- 20.8 to 195.2 +/- 23.5 U/L). There were no significant differences in strength gains based on prior training status or gender with HMB supplementation. The HMB group had a greater increase in upper body strength than the placebo group (HMB:7.5 +/- 0.6 kg; P:5.2 +/- 0.6 kg; P = 0.008). The HMB groups increased fat-free weight by 1.4 +/- 0.2 kg and decreased percent fat by 1.1% +/- 0.2% while the placebo groups increased fat-free weight by 0.9 +/- 0.2 kg and decreased percent fat by 0.5% +/- 0.2% (fat-free weight P = 0.08, percent fat P = 0.08, HMB compared to placebo). In summary, this is the first short-term study to investigate the roles of gender and training status on the effects of HMB supplementation on strength and body composition. This study showed, regardless of gender or training status, HMB may increase upper body strength and minimize muscle damage when combined with an exercise program.

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beta-hydroxy-beta-methylbutyrate (HMB) supplementation in humans is safe and may decrease cardiovascular risk factors.

J Nutr 2000 Aug;130(8):1937-45

Nissen S, Sharp RL, Panton L, Vukovich M, Trappe S, Fuller JC Jr.

Iowa State University, Ames, USA.

The leucine metabolite, beta-hydroxy-beta-methylbutyrate (HMB) enhances the effects of exercise on muscle size and strength. Although several reports in animals and humans indicate that HMB is safe, quantitative safety data in humans have not been reported definitively. The objective of this work was to summarize safety data collected in nine studies in which humans were fed 3 g HMB/d. The studies were from 3 to 8 wk in duration, included both males and females, young and old, exercising or nonexercising. Organ and tissue function was assessed by blood chemistry and hematology; subtle effects on emotional perception were measured with an emotional profile test (Circumplex), and tolerance of HMB was assessed with a battery of 32 health-related questions. HMB did not adversely affect any surrogate marker of tissue health and function. The Circumplex emotion profile indicated that HMB significantly decreased (improved) one indicator of negative mood (Unactivated Unpleasant Affect category, P < 0.05). No untoward effects of HMB were indicated. Compared with the placebo, HMB supplementation resulted in a net decrease in total cholesterol (5.8%, P < 0.03), a decrease in LDL cholesterol (7.3%, P < 0.01) and a decrease in systolic blood pressure (4.4 mm Hg, P < 0.05). These effects of HMB on surrogate markers of cardiovascular health could result in a decrease in the risk of heart attack and stroke. In conclusion, the objective data collected across nine experiments indicate that HMB can be taken safely as an ergogenic aid for exercise and that objective measures of health and perception of well-being are generally enhanced

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Leucine supplementation and intensive training.

Sports Med 1999 Jun;27(6):347-58

Mero A.

Department of Biology of Physical Activity, University of Jyvaskyla, Finland. mero@maila.jyu.fi

Leucine, isoleucine and valine, the branched-chain amino acids (BCAA), make up about one-third of muscle protein. Of these, leucine has been the most thoroughly investigated because its oxidation rate is higher than that of isoleucine or valine. Leucine also stimulates protein synthesis in muscle and is closely associated with the release of gluconeogenic precursors, such as alanine, from muscle. Significant decreases in plasma or serum levels of leucine occur following aerobic (11 to 33%), anaerobic lactic (5 to 8%) and strength exercise (30%) sessions. In skeletal muscle, there is a decrease in leucine level and a reduction in glycogen stores during exhaustive aerobic exercise. Basal fasting serum leucine levels decrease by 20% during 5 weeks of speed and strength training in power-trained athletes on a daily protein intake of 1.26 g/kg bodyweight. The leucine content of protein is assumed to vary between 5 and 10%. There are suggestions that the current recommended dietary intake of leucine be increased from 14 mg/kg bodyweight/day to a minimum of 45 mg/kg bodyweight/day for sedentary individuals, and more for those participating in intensive training in order to optimise rates of whole body protein synthesis. Consumption of BCAA (30 to 35% leucine) before or during endurance exercise may prevent or decrease the net rate of protein degradation, may improve both mental and physical performance and may have a sparing effect on muscle glycogen degradation and depletion of muscle glycogen stores. However, leucine supplementation (200 mg/kg bodyweight) 50 minutes before anaerobic running exercise had no effect on performance. During 5 weeks of strength and speed training, leucine supplementation of 50 mg/kg bodyweight/day, supplementary to a daily protein intake of 1.26 g/kg bodyweight/day, appeared to prevent the decrease in the serum leucine levels in power-trained athletes. According to 1 study, dietary supplementation of the leucine metabolite beta-hydroxy-beta-methylbutyrate (HMB) 3 g/day to humans undertaking intensive resistance training exercise resulted in an increased deposition of fat-free mass and an accompanying increase in strength. Muscle proteolysis was also decreased with HMB, accompanied by lower plasma levels of enzymes indicating muscle damage and an average 50% decrease in plasma essential amino acid levels. Furthermore, BCAA supplementation (76% leucine) in combination with moderate energy restriction has been shown to induce significant and preferential losses of visceral adipose tissue and to allow maintenance of a high level of performance. Caution must be paid when interpreting the limited number of studies in this area since, in many studies, leucine has been supplemented as part of a mixture of BCAA. Consequently, further research into the effects of leucine supplementation alone is needed

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Effect of leucine metabolite beta-hydroxy-beta-methylbutyrate on muscle metabolism during resistance-exercise training.

J Appl Physiol 1996 Nov;81(5):2095-104

Nissen S, Sharp R, Ray M, Rathmacher JA, Rice D, Fuller JC Jr, Connelly AS, Abumrad N.

Iowa State University, Ames 50011, USA.

The effects of dietary supplementation with the leucine metabolite beta-hydroxy-beta-methylbutyrate (HMB) were studied in two experiments. In study 1, subjects (n = 41) were randomized among three levels of HMB supplementation (0, 1.5 or 3.0 g HMB/day) and two protein levels (normal, 117 g/day, or high, 175 g/day) and weight lifted for 1.5 h 3 days/wk for 3 wk. In study 2, subjects (n = 28) were fed either 0 or 3.0 g HMB/day and weight lifted for 2-3 h 6 days/wk for 7 wk. In study 1, HMB significantly decreased the exercise-induced rise in muscle proteolysis as measured by urine 3-methylhistidine during the first 2 wk of exercise (linear decrease, P < 0.04). Plasma creatine phosphokinase was also decreased with HMB supplementation (week 3, linear decrease, P < 0.05). Weight lifted was increased by HMB supplementation when compared with the unsupplemented subjects during each week of the study (linear increase, P < 0.02). In study 2, fat-free mass was significantly increased in HMB-supplemented subjects compared with the unsupplemented group at 2 and 4-6 wk of the study (P < 0.05). In conclusion, supplementation with either 1.5 or 3 g HMB/day can partly prevent exercise-induced proteolysis and/or muscle damage and result in larger gains in muscle function associated with resistance training

[Baahh]

HMB er komplisert. Her forklarer Blade litt om det:

HMB

An understanding of HMB is critical if you are to get any benefit from it.

How does HMB affect muscle mass and strength? It isn?t through anabolism, and it appears not to be directly through anticatabolic mechanisms either. If you recall the pathway for leucine metabolism, you?ll notice that the fate of ingested HMB is mainly as HMG-CoA, a substrate for cholesterol synthesis. It appears that cholesterol synthesis may be a rate-limiting step in membrane repair after intense training. Keep in mind that muscle cells do not use circulating cholesterol for membrane repair. They must manufacture cholesterol from scratch (i.e. through the HMG-CoA pathway).

HMB won?t help if you are not training in such a way as to cause microtrauma to the cell membrane. HST however does cause frequent microtrauma and I personally have felt subjective benefits from HMB supplementation. Mostly, a sense of faster recovery and less noticeable ?stiffness? in the morning after.

Take it in divided doses evenly spaced. Take at least one dose right before and another right after training. This is to take advantage of blood flow to the muscle.

I DO recommend HMB. It won't do much for guys who have been using the same weight for months without any gains, but for HST it is perfectly suited. It will help keep you lean too.

If you do decide to use it, use it during the entire cycle. 3-4 grams per day is a suitable dosage depending on your weight. If you are over 200 pounds I would recommend 4 grams. HMB's effectiveness does not increase with escalating doses above ~4 grams. Try to split it up throughout the day as much as possible. Make sure to take some right before training when blood flow to muscle is highest.

HMB does not interact with any other supplements so it can be taken whith any or all other supplements.

It won't do anything during Strategic Deconditioning so don't take it then.


HMB appears to be converted mostly to beta-hydroxy-beta-methylglutaryl CoA (HMG-CoA). HMG-CoA is then used to make cholesterol within cells. This is important for muscle cells in that they cannot use cholesterol from the blood.

Here is where much of the misunderstanding about HMB comes in. HMB has NOT been shown to directly inhibit protein breakdown, and certainly does not cause protein synthesis. A study done in 1997 looked at the effects of giving lambs high doses of HMB (Br J Nutr. 1997 Jun;77(6):885-96). To their surprise, HMB did not have any effect on protein catabolism or anabolism. In essence, HMB didn?t do squat under normal conditions.

So, if you are expecting HMB to "build" muscle you are going to be disappointed. If the "noticeable effect" you are looking for is anabolism, you are going to be disappointed.

However you?ll notice that the fate of ingested HMB is mainly to be converted to HMG-CoA, a substrate for cholesterol synthesis. It appears that cholesterol synthesis may be a rate-limiting step in membrane repair after intense training.

HMB significantly decreased the exercise-induced rise in muscle breakdown as measured by urine 3-methylhistidine and CK during the first 2 wk of exercise. In the studies showing an effect of HMB on muscle breakdown, the differences between the HMB group and the placebo group tend to decline over a period of about 3-4 weeks until at about 4-5 weeks there is no difference in the above markers of damage, including 3-MH. This reflects the fact that, if the cholesterol mechanism is true, HMB serves to facilitate rates of growth only when membrane integrity is a limiting factor. This generally occurs during the first two to three weeks of a new or unaccustomed exercise program. After that, muscles become resistant to further damage (repeated bout effect, or rapid training effect) induced by that particular program (loading regimen) and HMB supplementation loses its usefulness.

HST is characterized by a constant increase in load following a period of Strategic Deconditioning. Therefore, when followed with the appropriate frequency, you stay just ahead of the structural recovery curve. This keeps you constantly in a state of muscle damage. This appears to be the only time when HMB is useful.

In traditional routines you use the same weight until you can add more because your strength has increased. I?ve seen guys use the same weight on their lifts workout after workout for months or even years at a time. Their muscle tissue is tuff as shoe leather and there virtually NO structural damage to the tissue after any workout. They simply walk out of the gym with their butt kicked but with no new muscle to show for it?for months at a time! HMB facilitates ?recovery? from frequent heavy bouts of training typical of HST. I have experienced increased exercise tolerance when using it. No I didn?t measure anything, I just felt better and stronger with fewer aches and pains.

I haven?t even began to talk about the benefits of the calcium in HMB with respect to fat cell metabolism: (J Am Coll Nutr. 2002 Apr;21(2):146S-151S.; FASEB J. 2000 Jun;14(9):1132-8.; FASEB J. 2001 Feb;15(2):291-3.; J Am Coll Nutr. 2001 Oct;20(5 Suppl):428S-435S; discussion 440S-442S.)

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Jeg har selv testet HMB 2 ganger, begge gangene var det ved kaloripluss, en gang med kreatin citrate og en gang med kreatin monohydrate...

Jeg merket akkurat det samme som Blade skriver.
Raskere etterhenting og mindre muskelstivhet ved inntak av HMB i tilleg til kreatin vs kun kreatin citrate, monohydrate...

Bakdelen med HMB er prisen. Jeg syntes ikke effekten av HMB stod i forhold til hva jeg betalte for det (Noen år siden)..
Nå er HMB blitt noe billigere og jeg vurderer å bruke det igjen..

HMB alene uten kreatin på kaloripluss diet vil nok ikke gi de helt store resultatene, men tatt sammens med kreatin så får du en synergisk mer effekt..

Den største fordelen jeg ser med HMB er å ta det på en kalori minus diet for å beholde muskelmassen.. I følge studiene som er gjort ser det faktiskut til at HMB (kan)/er (gjøre) mer nytt(e)ig (for seg) på en kalori minus diet (og kalori positiv for den saks skyld) en Feks L-glutamin (noen positive studier ved kalori minus) og Glutamin peptid (noen fler positive studier ved kalori minus)