HMB: A Game Changer for Aerobic Fitness and Strength

For those of you who don’t know, HMB (beta-hydroxy beta-methylbutyrate) has been around for a long time, but lost its glamour after a few studies questioned its efficacy in fit/trained individuals; hence, HMB has been generally prescribed for those just beginning a workout program.  Notably, past HMB studies using highly trained/fit subjects are generally fraught with problems in research design, where workout programs are not intense enough and/or HMB doses are not high enough to promote gains.  

Well, recent evidence from a pair of new studies should rekindle your excitement for HMB as a potent supplement that quickly builds aerobic fitness, strength, and muscularity. In a recent clinical trial, published in the Journal of the International Society of Sports Nutrition, researchers from University of Central Florida tested the efficacy of HMB supplementation or placebo (3 g/day) on boosting the training effect of high intensity interval training (HIIT) in fit and active male and female subjects. They reported that after only 4 weeks training , subjects who took HMB raised their VO2 peak (a measure of aerobic fitness) by approximately 5%— this is remarkable considering the subjects commenced the study with relatively high levels of aerobic fitness. In another recent study, published in the European Journal of Applied Physiology, scientists from University of Tampa (Florida) tested the effects of HMB supplementation or placebo (3 g/day) in combination with a 12 week periodized resistance-training program in well-trained men. They reported that those who took HMB saw greater gains in overall body mass, lean body mass, strength, and power and decreased body fat compared to those who took the placebo. Furthermore, subjects who took HMB had significantly lower cortisol (a catabolic hormone) levels and greater perceptions of recovery between training bouts. 

References:

Wilson JM, Lowery RP, Joy JM, Andersen JC, Wilson SM, Stout JR, Duncan N, Fuller JC, Baier SM, Naimo MA, Rathmacher J. The effects of 12 weeks of beta-hydroxy-beta-methylbutyrate free acid supplementation on muscle mass, strength, and power in resistance-trained individuals: a randomized, double-blind, placebo-controlled study. Eur J Appl Physiol. 2014 Jun;114(6):1217-27. doi: 10.1007/s00421-014-2854-5. Epub 2014 Mar 6.

Robinson EH 4th, Stout JR, Miramonti AA, Fukuda DH, Wang R, Townsend JR, Mangine GT, Fragala MS, Hoffman JR. High-intensity interval training and β-hydroxy-β-methylbutyric free acid improves aerobic power and metabolic thresholds. J Int Soc Sports Nutr. 2014 Apr 26;11:16. doi: 10.1186/1550-2783-11-16. eCollection 2014.