HMB (beta-hydroxy-beta-methylbutyrate) was all the craze in early 2000, but how does it stack up today? Based on a May 2009 study published in the Journal of Strength and Conditioning Research, HMB might see its final days on store shelves.
The dietary supplement beta-hydroxy-beta-methylbutyrate (HMB) is claimed to increase strength, lean body mass, and decrease fat mass when used in conjunction with resistance training. According to the nine-week long study, HMB had trivial effects on body mass and fat reduction. For strength, the 1-repetition maximum (1RM) for the bench press and bicep preacher curl were inconclusive, although the 1RM for the leg extension showed a substantial 9.1% increase. However the combined average strength measure was only 1.6% (+/-4.3%)1.
In a meta-analysis, involving 9 different studies, Rowlands et al examined the ergogenic effect that HMB had in both trained and untrained athletes. Results of their study indicated that in UNTRAINED individuals, HMB led to a moderate increase in strength gains of the lower body (9.9 +/- 5.9% <—-notice the huge variation) and small effects on upper body strength (2.1 +/- 5.5%). Negligible effects on both upper and lower body strength were seen with EXPERIENCED lifters.
Considering the expense of this raw ingredient, these studies suggests money might be better spent elsewhere.
References
1 Thomson JS, Watson PE, Rowlands DS. Effects of nine weeks of beta-hydroxy-beta-methylbutyrate supplementation on strength and body composition in resistance trained men. J Strength Cond Res. 2009 May;23(3):827-35.
2 Rowlands DS, Thomson JS. Effects of beta-hydroxy-beta-methylbutyrate supplementation during resistance training on strength, body composition, and muscle damage in trained and untrained young men: a meta-analysis. J Strength Cond Res. 2009 May;23(3):836-46.