More HMB Free Acid Science: Now It's Also Good For High Intensity Interval Training (HIIT) Says the Latest Sponsored Trial W/Out Calcium HMB Control in Young Men & Women

I still believe HMB is better suited for HIIT full body workouts than for cycling or running - regardless of whether it's the calcium or free acid form, by the way.

It should be obvious that it was the Journal of the International Society of Sports Nutrition, where I hit onto a very recent study by Edward H Robinson et al. (2014), a study the purpose of which it was to examine the effect of β-hydroxy-β-methylbutyric free acid (HMBFA) and cycle ergometry HIIT on maximal oxygen consumption (VO2peak), ventilatory threshold (VT), respiratory compensation point (RCP) and time to exhaustion in college-aged men and women." (Robinson. 2014).

That's not just quite a mouthful, and - this is where it becomes interesting - nothing that has not previously been studied in a comparable scenario with regular HMB (we will get back to why this is a problem in the conclusion).
Apropos scenario, what we are dealing with, here, is a double-blind, placebo-controlled design study, in the course of which all participants,  34 healthy men and women (Age: 22.7 ± 3.1 yrs ; VO2peak: 39.3 ± 5.0 ml/kg) who had volunteered to participate completed a series of tests prior to and following treatment (A peak oxygen consumption test was performed on a cycle ergometer to assess VO2peak, Tmax, VT, and RCP. ). 26 of the participants had been randomly assigned into either a placebo (PLA-HIIT) or 3 g per day of HMBFA (BetaTor™) (HMBFA-HIIT) group. The rest, eight participants served as sedentary controls (CTL) - well, as sedentary as college aged boys and girls usually are ;-) The participants who had been randomized to the exercise groups (PLA-HIIT and HMBFA-HIIT) completed 12 HIIT (80-120% maximal workload) exercise sessions consisting of 5–6 bouts of cycling at a work to rest ratio 2:1 - that's 2 minutes of all out cycle vs. 1 minute of total rest.

Figure 1: Changes in body composition in response to sitting around (control) and HIIT with (HMBFA-HIIT) and without (HMBFA-PLACEBO) supplementing 3g of the free acid form of HBM (Robinson. 2014)

The body composition of the participants, which was "identical" (within statistical margin) before the study, was measured with dual energy x-ray absorptiometry (DEXA) and the changes in fitness parameters were determined in a 2nd exercise test.
Against that background it's quite astonishing that the control group lost 10% of their total fat mass, right? Well, in view of the fact that this change was not significant, someone probably has been dieting here - not very successful, considering the absence of improvements in body fat %, by the way.

Figure 2: Time to exhaustion, respiratory compensation point (RCP) and power at respiratory compensation point (PRCP) in 34 healthy college-aged men and women after sitting around (CTL) or doing HIIT with (HMBFA-HIIT) or without the (PLA) the provision of 3g of the free acid form of β-hydroxy-β-methylbutyrate per day (Robinson. 2004)

Now you may argue that the absence of changes in body composition is awkward considering the significant improvements in time to exhaustion, the respiratory compensation point (RCP) and the power at respiratory compensation point (PRCP), which are all indicative of significant improvements in physical fitness (see Figure 2).

"The Fallacy of Working out To Burn Calories" | learn more

On the other hand, you as student of the SuppVersity should know that intense exercise alone won't make the love-handles go away. Unless you are also "working out in the kitchen", i.e. making changes to your diet, you are only spinning your wheels; and that in spite of the fact that "The Fallacy of Working Out To "Burn Calories" comes hand in hand with the surprising ability of exercise to shut down the carb cravings | learn more.

In essence, it's thus not the fact that the subjects didn't lose weight / body fat, but rather the absence of significant effects of the shiny new free acid form β-hydroxy-β-methylbutyrate (HMBFA) supplement on the exercise induced improvements in metabolic fitness you could consider disappointing before you've had another look at the data in Figure 3.
Figure 3 depicts the VO2peak obtained during graded exercise test, the power at ventilatory threshold (PVT) and the amount of air the subjects were gasping at this ventilatory Threshold (VT) and here - actually somewhat to my surprise - the supplement did what I suppose the producer is soon going to promise: It resulted in greater changes inVO2 peak, PVT and VT than HIIT alone.

Figure 3: Changes (% of baseline) in VO2peak, peak power, the power at ventilatory threshold (PVT) and the amount of air the subjects were gasping at this ventilatory Threshold (VT) obtained during graded exercise test (Robinson. 2014)

What I have to say, though, is that I am still a bit disappointed that similar benefits were not observed for the peak power, for which the changes in the placebo group (PLA-HIIT) were actually more significant (p = 0.018) than those in the HMBFA-HIIT group (p = 0.04) which were "just" significant.
References:

• Lamboley, Cédric RH, Donald Royer, and Isabelle J. Dionne. "Effects of β-Hydroxy-β-Methylbutyrate on Aerobic-Performance Components and Body Composition in College Students." International journal of sport nutrition & exercise metabolism 17.1 (2007).
• Wilson, Gabriel J., et al. "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." European Journal of Applied Physiology (2014)| learn more  in a previous SuppVersity article