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.
My thoughts... The key phrase in this study is "highly trained athletes". I recently did a ton of research on the effects of creatine on highly trained athletes, and it seems that they do not benefit as much as recreational athletes would. For most studies, researchers use "weekend athletes", and an occasional collegiate athlete, but never any professional athletes (or as far as i know, I've never seen a study done on pro sports players). So my guess is that maybe the body can become more efficient in using its energy systems, such as the phosphocreatine system, and over time, be able to use them to their maximum potential without having to introduce exogenous supplementation.
Posted by KEVIN JONES