EFFECTS OF Β-Hydroxy Β-Methylbutyrate ON POWER PERFORMANCE AND INDICES OF MUSCLE DAMAGE AND STRESS DURING HIGH-INTENSITY TRAINING

Abstract

Hoffman, J.R., J. Cooper, M. Wendell, J. Im, and J. Kang. Effects of ␤-hydroxy ␤-methylbutyrate on power performance and indices of muscle damage and stress during high intensity training. J. Strength Cond. Res. 18(4): 000-000. 2004.-Twenty-six members of a collegiate football team were randomly assigned to either a supplement (S) (3 g of ␤-hydroxy ␤-methylbutyrate [HMB] per day) or placebo (P) group. Testing occurred before (PRE) and at the end of 10 days of preseason football training camp (POST). During each testing session, subjects performed an anaerobic power test, and blood samples were obtained for testosterone, cortisol, creatine kinase, and myoglobin analysis. No differences in anaerobic power were seen between PRE and POST in either group. Cortisol concentrations were significantly decreased from PRE (333 Ϯ 81 nmol·L Ϫ1 ) to POST (246 Ϯ 79 nmol·L Ϫ1 ), and a sixfold increase was seen in creatine kinase concentrations at POST. However, no significant differences between the groups were seen. No significant time or group effects were observed in testosterone or myoglobin concentrations. Results suggest that short duration HMB supplementation does not provide any ergogenic benefit in collegiate football players during preseason training camp.

Resistance training & beta-hydroxy-beta-methylbutyrate supplementation on hormones

“…These results repeated in Thomson et al 22 study in trained men after 9 weeks resistance training. But these findings are not supported by several investigations 8,9,16,24,27,28 .…”

“…Although some findings suggest that HMB supplementation during training may enhances adaptations of trained and untrained individuals, others report no significant effects of HMB supplementation 8,16,17 . Thus, the available scientific literature on HMB supplementation in humans is still preliminary in nature and should be considered with reservation 11,18 .Also, the data about the influence of HMB supplementation, particularly with resistance training, on anabolic-catabolic hormones are still scarce and to our knowledge there are only two studies with conflicting results 5,11 in the literature regarding the effect of HMB supplementation on these variables.…”

β-hydroxy-β-methylbutyrate (HMβ), Physical training and skeletal muscle: a systematic review

“…WENDELL et al, 2004;O'CONNOR and CROWE, 2003;RANSONE, NEIGHBORS, LEFAVI et al, 2003;SLATER, JENKINS, LOGAN et al, 2001), supplementation had no ergogenic effect.…”

Competitive Edge: Review of the Role of Glutamine, Arginine and β -Hydroxy- β -Methylbutyrate Supplements for Enhancing Athletic Performance in Addition to Benefiting the Body During Times of Stress, Illness and Wound Healing

“…Therefore, HMB has been studied as a sports performance supplement for enhancing strength and muscle mass. The research is promising but contradictory and limited to small studies [18,[20][21][22][23][24][25][30][31][32][33][34][35]. Some studies of small double-blind trials have been negative [30,35].…”