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FlexMaster 08-08-2006 04:08 AM

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

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.

Short-term beta-hydroxy-beta-methylbutyrate supplementation does not reduce symptoms of eccentric muscle damage.

Paddon-Jones D, Keech A, Jenkins D.

School of Human Movement Studies at The University of Queensland, Brisbane, Australia. djpaddon@utmb.edu

PURPOSE: We examined the effects of short-term beta-hydroxy-beta-methylbutyrate (HMB) supplementation on symptoms of muscle damage following an acute bout of eccentric exercise. METHODS: Non-resistance trained subjects were randomly assigned to a HMB supplement group (HMB, 40mg/kg bodyweight/day, n = 8) or placebo group (CON, n = 9). Supplementation commenced 6 days prior to a bout of 24 maximal isokinetic eccentric contractions of the elbow flexors and continued throughout post-testing. Muscle soreness, upper arm girth, and torque measures were assessed pre-exercise, 15 min post-exercise, and 1, 2, 3, 4, 7, and 10 days post-exercise. RESULTS: No pre-test differences between HMB and CON groups were identified, and both performed a similar amount of eccentric work during the main eccentric exercise bout (p > .05). HMB supplementation had no effect on swelling, muscle soreness, or torque following the damaging eccentric exercise bout (p > .05). CONCLUSION: Compared to a placebo condition, short-term supplementation with 40mg/kg bodyweight/day of HMB had no beneficial effect on a range of symptoms associated with eccentric muscle damage. If HMB can produce an ergogenic response, a longer preexercise supplementation period may be necessary.

Beta-hydroxy-beta-methylbutyrate (HMB) supplementation does not affect changes in strength or body composition during resistance training in trained men.

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.

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

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.

Fahsy 08-08-2006 02:40 PM

Re: Studies against HMB
 
With any supplement there will be studies both supporting supplementation and against it. That's one side of HMB findings, there are other studies (which you can find referenced in the HMB article here on ABC) which support supplementation. Personally I found that HMB has seemed to help my gains (whether it is a placebo effect or due to other variables I cannot say for sure) and I will continue to supplement with it.

ryancostill 08-08-2006 05:12 PM

Re: Studies against HMB
 
Thanks for posting these studies. HMB is a research area about which I have to admit I know little about but am eager to learn more.

Have you rad these full articles? How do the full training programs look? Are they hypertrophy orientated? Do you think the training protocols were demanding enough to illicit significant muscle breakdown?

I will be interested in hearing what some of the other views on this are.

Venom 08-08-2006 09:46 PM

Re: Studies against HMB
 
Jake and I just submitted a 68 page, manuscript on HMB, with over 130 references, to The Journal of Applied Physiology; by far the most extensive review paper on HMB to date. Every article in existence that we are aware off, was analyzed. There are a ton of studies which support the efficacy of HMB in the elderaly, advanced athletes, new athletes, and numerous states of muscle catabolism. But, there are some contradictory results. Therefore, we have a section where we analyze possible reasons for conflicting results, and how future studies can solve these problems. It is going to clear up a lot of issues I think in the HMB literature.

ryancostill 08-08-2006 10:07 PM

Re: Studies against HMB
 
[ QUOTE ]
Jake and I just submitted a 68 page, manuscript on HMB, with over 130 references, to The Journal of Applied Physiology;

[/ QUOTE ]

Wow. Let me just say to those who dont know that the journal of applied physiology is about as prestigous a journal as you could have possibly submitted such a journal to.

Good luck! Has it been reviewed yet?

Venom 08-08-2006 10:40 PM

Re: Studies against HMB
 
Yeah, like Ryan said, it is such a privledge. If we get accepted to there...wow, words could not describe how happy that would make us. [img]/forum/images/graemlins/grin.gif[/img] The fact that we submitted there definitely made us go through the paper a ton of times, to assure it was high quality.

We just submitted it a few days ago. But they should be reviewing it soon. We'll keep you guys up to date. [img]/forum/images/graemlins/smile.gif[/img]

TheShanMan 08-09-2006 12:25 PM

Re: Studies against HMB
 
That's awesome, Venom!


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