HMB Exhibits Differential Effects on ATP and Glycogen Content of Fast & Slow Twitch Fibers and Maximizes Tetanic Force Development in Rodent Study

Image 1: This is where HMB could actually make a difference, the two more reps, the one more sprint, which after weeks and months of training can decide over victory or defeat.

Sometimes, or I should say, time and again (!), it amazes me how the same people who are willing to invest hundreds of bucks in a supplement, which (according to the patent holder) "has been shown in scientitfic studies" (which were conducted by the researcher and a buddy of his at a remote lab, only to file the patent) to "increase testosterone by up to 147.34%", keep telling me that they "would never waste their hard earned money on supplements like HMB..." hello? Am I missing something, here? I mean, right; HMB does not produce the steroid-like effects the same sort of shady businessmen who are now promoting a new natural testosterone booster as legal alternative to Anavar on a monthly base once claimed it would have, but in all  honesty, the scientific research on HMB is by far more promising than the mostly non-existent research on 99% of the "legal anabolics" out there.

HMB works, we just don't know exactly how and for whom

As Dr. Connelly pointed out on the last BodyRX Show (highly recommended, especially for Layne's intellectual exchange with Dr. Jeff Volek), it stands out of question that HMB works. There are in fact more than a dozen of studies which show that supplementation with adequate amounts of this leucine metabolite has anti-catabolic effects in various conditions of skeletal muscle atrophy (Nissen. 2003; Smith. 2005). What  is still debatable, though is whether and to which extent athletes, in general, and bodybuilders, in particular can benefit from these effects. In view of the increasing awareness of the importance of leucine, the metabolic precursor of b-hydroxy-b-methylbutyrate (HMB), most athletes in this subgroup probably consume somwhere between 20-30g of leucine from the 300g of protein they are feeding themselves in the form of protein shakes and lean meats alone (with reference to the data that is presented in figure 1 it is noteworthy that the comparison Nissen made is not "fair", because the many of the HMB studies were conducted with "sick" people, while the majority of studies on protein supplements used either healthy people or athletes). With an average conversion rate of ~5% (of dietary leucine), we would have to estimate their daily HMB "production" to roughly 1.0-1.5g, which is interestingly at the lower range of what has been shown to ameliorate muscle wasting in cancer cachexia studies (Eley. 2007; Kovarik. 2010).

Figure 1: Calculated effect sizes of creatine, HMB, chromium, androstendione, DHEA and protein supplements on strength and lean mass gains (adapted from meta-review by Nissen et al.; Nissen. 2003)

And even if we discard the question of whether or not additional HMB is really necessary on a high protein diet and whether or not respective dietary differences could explain the negative results from some, yet by no means all, trials with professional athletes, we must still admit that even in those cases where it does work, we (i.e. scientists) do not really understand how HMB does its anti-proteolytic magic. The results of a recently published study from scientists from the Institute of Biomedical Science at the University of Sao Paulo, could thusly be of particular importance, as this is - at least to my mind - the first study to investigate the effects HMB supplementation had on ATP and glycogen levels, citrate synthase and changes in the contractive properties of individual muscle fibers (Pinheiro. 2011).

Figure 2: Changes (vs. placebo) in ATP and glycogen content, as well as citrate synthesis in red and white portion of rat gastrocnemius muscle after 4 week supplementation with 320mg/kg HMB (data adapted from Pinheiro. 2011)

The data in figure 2 shows, that after 4 weeks of daily supplementation with 320mg/kg HMB (in the study the usual calcium salt, you can buy in bulk on the Internet was used), the ATP and glycogen levels in the gastrocnemius muscle of the rats were profoundly elevated. In that, it is particularly interesting that the leucine metabolite had differential effects on the slow-twitch oxidative red portion of the muscle and the fast-twitch glycolytic white portion: In the slow twitch fibers the increase in ATP is 10x higher than it is in the fast twitch fibers, where the +400% increase in glycogen content should yet provide a similarly extensive buffer of readily (yet not immediately) available energy. Moreover, the increase in citrate synthesis (+67%) in the slow twitch fibers suggests that part of this effect was mediated by an "increased lipid availability due to increased lipolysis", or, put simply, by an increased oxidation of fatty acids to generate more ATP.

Figure 3: Tetanic force production (normalized to muscle weight) in rats receiving 320mg/kg HMB or placebo for 4-weeks; successive tetanic contractions were evoked at 100 Hz each 10 s of interval (data adapted from Pinheiro. 2011)

These increase in both readily available energy stores and the ability to replenish the former via fatty acid oxidation, is - according to Pinheiro et al. - also the underlying reason for the "increase in resistance to fatique" the scientists observed when they subjected the rat muscle to electrical stimulation in order to evaluate the tetanic (=constantly contracting) force production (cf. figure 3). Contrary to the twitch force, which was identical in supplemented and non-supplemented rats, the tetanic force production (normalized for either muscle weight or muscle cross-sectional area) increased by +17% (p<0.05; meaning that the chance that this was mere coincidence is <5%).

Fine!? Now, tell me: Is HMB worth it?

In view of the fact that neither the muscle size (cross-sectional area) nor the lean mass of the rodents in the HMB group differed from their placebo supplemented peers (btw. the animals were not "trained" in the course of the 4-week study), we must conclude that the effects of HMB, similar to those of creatine, are not what you would call "immediately anabolic". In a real world training scenario the metabolic advantage (increased ATP stores, increased glycogen stores and increased oxidative capacity) the rats in the HMB group gained over the 4-week study period, would allow trainees to do those 1-2 reps more which in weeks and months would then translate into this one additional pound of muscle or the 10th of a second that can make the difference between victory or defeat - whether those 1-2 reps are worth the roughly 64$ it would cost to copy the supplementation regimen used in the study (320mg/kg in rats would equate to 53mg/kg per day for humans), does yet depend on who you are, what you want to achieve and how much money you have to spend... and if you do not have your regular diet and training in check, don't even think of HMB (let alone one of those "test boosters" ;-)

HMB Supplementation: Pre- or Pre- and Post-Workout? Anti- or Pro-Inflammatory? MA Thesis Offers Food for Thought

Supplement facts: "Is as potent as the weak androgen Oxmethalone aka Anavar!" If that's how you advertise an expensive dietary supplement that tastes like poison, you better make sure your product delivers. For HMB the supplement companies must have overlooked that their clientele is in no way similar to the elderly subjects from their references with their protein deficient diets... the result? An epic fail for both the consumers who felt ripped off and the producers who probably expected this to be a long-term investment!

HMB was once hailed to be as effective as a "weak" androgen such as Anavar. No wonder that dozens of consumers were pretty  disappointed, when they added it on top of their already protein and, at that times more or less coincidentally, leucine-laden diets and saw... nothing. Well, at least no gains that would even remotely remind anyone of Oxymetholone. With no costumer being interest to pay the extra bucks for the (at that time still) very expensive product, it was no wonder that the leucine metabolite β-Hydroxy β-methylbutyric acid (HMB) disappeared from the market relatively quickly.

I bet, the fact that it tastes like poison did not really help either. after all it is downright impossible to add an effective amount of HMB into a powdered supplement, if you do not want to totally ruin the taste of the product.

As a SuppVersity reader you will yet be aware that HMB is still no epic fail (read all older posts on HMB). Its marginal utility, however, is exactly that: Marginal -- at least when someone is taking it on top of tons of leucine rich protein powders, BCAAs and whatever else.

HMB is not useless and there appears to be much we have to learn about it

Despite the fact that it is very unlikely that taking HMB will turn you into a second Phil Health within weeks, its hitherto not fully understood beneficial effects on body fat, its effects on GH and IGF-1 as well as open questions that are related to our own bodies ability to produce HMB from leucine and whether this conversion mediated some of the benefits of the #1 among the BCAAs (=leucine) clearly indicate that there remains a lot to learn about Dr. Steven L. Nissen's 1996 discovery (Nissen. 1996).

One of those things we still have... or I should say had to learn pertains the effect of HMB on the exercise induced expression of inflammatory cytokines, which turned out to be totally different from what Paul Raymond Vulcan, a student who has recently submitted his Master Thesis on the "Role of β-hydroxy-β-methylbutyrate (HMB) on inflammation after eccentric exercise" at the Iowa State University probably expected, when he recruited the 16 female and 16 male, untrained volunteers (mean age 3±0.30y, mean weight 67.5±0.9kg, and mean hight 172.2±0.7cm) for his study.

'Extend your legs' till they burn ;-)

The study consisted of a single exercise + supplementation trial in the course of which the participants underwent the following supplementation regimen:

A note on the supplementation protocol: The way Volcan describes the protocol is at least "suboptimal". If I am getting it correctly (mostly by looking at a graphical outline) the participants in the pre/post trial received HMB not just on day 0, but also on day 1, day 2, day 3 and day 4 - always with lunch and dinner.

"Experimental groups received supplement in one of the following manners: placebo pre- & post-exercise (CON), HMB pre-exercise (PRE) in either a calcium salt form or a free acid gel, HMB pre- & post-exercise (PRE/POST) in either a calcium salt form or a free acid gel.Supplements were given in a double-blind protocol so that investigators were also blind to the contents of the supplements throughout the study.  Originally, the study called for 5 treatment groups with a separation of calcium salt groups from the free acid gel groups. Due to sample sizes, groups receiving the same quantity of HMB were consolidated for statistical reasons." (Volcan. 2012)

While it is certainly somewhat disappointing that we don't have a comparison of the salt and the gel variant of HMB (you will see the first gels hit the market, very soon, believe me),  this is understandable given the small sample size. What is yet a clear greenhorn mistake, however, is that Volcan does not disclose the amount of HMB salt the participants received. He states that the gel syringes contained 3ml but since I have no clue what else (besides HMB) is in the gel, I cannot tell you how much HMB the groups actually received (let alone calculate the equivalent in term of calcium-hmb).

Standard protocol, surprising results

Aside from this lapse the general protocol of the study looks pretty solid. The original challenge on day 0, which consisted of 3 sets of 50 eccentric leg extensions (both legs, 0° to 90°, 60°/sec; 3s per rep, 2 min rest between sets), was preceded and followed by a combination of

• urine collection, 
• muscle soreness test, 
• leg circumference measurements, 
• blood collection and a 
• strength test

which took place on day 0 (before the exercise protocol), 24h, 48h, 72h and 96h post. And I guess you could say "fortunately", the analysis of the respective data yielded not exactly what Volcan had expected. Firstly many expected effects did not occur (at least not if you consider only statistical significant inter-group effects), e.g. there were no differences for markers of muscle damage:

• creatine kinase (CK) 
• lactate dehydrogenase (LDH) and 
• 3-methyl histidine (3-MH)

Some did however show a trend (which did not reach statistical significance due to the small sample size) and / or did reach statistical significance at a certain time point only:

• 

  Figure 1: Peak performance force (in N) on the days after the leg extensions (based on Volcan. 2012). As you can see it's not like there had not been any effects, but with the small sample size few made it over the p < 0.05 hurdle, or put simply were "statistically significant".

  creatine kinase (CK) showed a non-statistically significant reduction in PRE/POST, while it was identical in PRE and CON (1593 IU compared to 3514 IU and 4068 IU; this is a candidate that would almost certainly have reached statistical significance with a larger number of participants, because the CK response shows high inter-individual variability)
• the decrease in right leg peak force was about 16% in the CON group compared to 9% and 7% in the PRE and PRE/POST groups, respectively
• the muscle soreness was also not significantly different between groups
• the difference in the loss of peak force was only significant on day two when the peak performance in the control group dropped significantly (see figure 1)

So far the somewhat disheartening but not actually novel part of the study. With the data in figure 2, however we are actually approaching the real news part of today's post:

Figure 2: Makers of inflammation (IL-1 and TNF-alpha) after 3x50 leg extension on the test day, as well as 24h, 48h, 72h and 96h post (based on Vulcan. 2012)

Take a close look and don't be fooled like I was, when I initially looked at the results and almost automatically assumed that there was a reduction in TNF-alpha and IL-1 in the group that recevived the most HMB (I must say I had only the poor black and white graphs from the original study and not the full-service pack you get, here at the SuppVersity, though ;-)

"I mean, good things reduce inflammation, right?"

Wrong, at least in the case of HMB, which certainly is a good thing, this is not the case. HMB does not reduce inflammation and that despite the fact that it works like a charm for those people of whom we are told that inflammation was the last thing they would need, namely the elderly. And still it appears as if the increased inflammatory response to the muscle damaging exercise on day 0 could actually be part of how HMB works. Volcan realizes that and states:

Just in case you don't want to believe that inflammation could play a beneficial role in the regeneration and even the subsequent super-compensation process at the end of which both your muscle strength and muscle size will go up, I suggest you read the respective installment of the Intermittent Thoughts

"The results of TNF-α and IL-1ra support the theory that inflammation is affected by HMB. In  both cases the CON group experienced a decline in serum concentration and the dip was reduced or limited by supplementation of HMB.  These results could be interpreted as an increase in the inflammatory response following HMB supplementation [...] This suggests that HMB creates a greater inflammatory response which may improve recovery of damaged tissue. When exactly this occurs and how, whether direct or indirect, is not evident from this study. We already kno that proteolysis is affected by HMB and it is also possible that inflammatory cytokines are mediating an optimal recovery." (my emphases in Volcan. 2012)

Edited: While this sounds like an excellent hypothesis there is one thing Volcan has overlooked (and me too, at least initially, thus the update). The current scientific evidence suggest that the IL-1 receptor is like a multifaceted chimera. Or put simply, in its conventional form it will accept IL-1 and thus have exert pro-inflammatory downstream effects. IL-1-RA, which is the variant Volcan measured here, actually does the opposite, though: IL-1-RA blocks the inflammatory effects of IL-1 (Arend. 1997).

In the end, this does not really change my previous assertion that "You need to go beyond the 'all inflammation is bad' paradigm and see 'inflammation', or what we usually refer to as inflammation as what it really is, namely a per se physiological reaction of our bodies that can be good, appropriate and highly desirable or bad, misplaced and highly detrimental depending on the circumstances." It just adds another level of complexity to that statement. And this added dimension can actually explain why HMB works in the elderly, but does not work (at least not to the same degree in young people). Old people have high IL-1 (the pro-inflammatory varieties), young and healthy people don't, so blocking IL-1 signaling will have more pronounced effect in the older ones of you than in the young chaps, who will probably fare quite well with nothing but a leucine rich protein shake.

References:

• Arend WP. Interleukin 1 receptor antagonist. A new member of the interleukin 1 family. J Clin Invest. 1991 Nov;88(5):1445-51.
• Nissen SR, Sharp M, Ray JA, Rathmacher D, Rice JC, Fuller Jr, Connelly AS, Abumrad N: Effect of leucine metabolite beta -hydroxy-beta -methylbutyrate on muscle metabolism during resistance-exercise training. J Appl Physiol 1996, 81:2095-2104.
• Volcan PR. Role of β-Hydroxy-β-methylbutyrate (HMB) on inflammation after eccentric exercise. Graduate Theses and Dissertations. 2012; paper 12501.

Milk, a Glucose Uptake Promoter That's More Than the Sum of Its Parts. Plus: HICA & HMB in Yogurt. How Much EAA in Your Protein? Raw Milk Does not Cure Lactose Intolerance

Milk is one of the few foods that are advertized by celebrities that could actually be good for you (photo from the "Got Milk" campaign)

I hope you are not fed up with milk and dairy, yet, because today's SuppVersity short news have a ton of it. What exactly?

Well, after taking a closer look at the surprisingly high amount of HICA and the comparatively small amount of HMB in yogurt and reviewing the EAA content of six common protein sources, we are going to delve deeper into the latest evidence that shows that milk is much more than the sum of its parts, i.e. milk protein, lactose and fat and conclude on a note on another widely known Internet myth that says that people with lactose intolerance could drink raw milk without a problem.

You can learn more about dairy at the SuppVersity

Dairy Has Branched-Chain Fatty Acids!

Is There Sth. Like a Dairy Weight Loss Miracle?

There is Good A2 and Bad A1 Dairy, True or False?

Lactulose For Your Gut & Overall Health

Is There a "Fat Advantage" for Dairy Lovers

Dairy, Diabetes, Estrogen, IGF-1, Cancer & More

• 

  Figure 1: Amount of HICA & HMB (in µg/L) in commercial whole milk and yogurt (Ehling. 2014)

  Significant amounts of HMB and specifically HICA in yogurt. We all know that yogurt is among the dairy products with the most evidence of significant health benefits. That yogurt could be a decent muscle builder, on the other hand, would be news.
  
  With ~5 mg of β-hydroxy-β-methylbutyric acid (HMB) and up to 12.5 mg of α-hydroxyisocaproic acid (HICA) yogurt would have what it takes if the values of HMB and HICA Stefan Ehling and Todime M. Reddy measured in regular yogurt were on a per gram, not a per liter basis (Ehling. 2014).
• How much EAA in my protein? Since I have been repeatedly questioned about the essential amino acid content in whey, milk, soy, and egg protein. I have published Table 1 which originally appeared in a 2010 study by Hulmi et al. on Facebook, already.

  

  Table 1: Approximate amino acid composition of popular protein powders (Hulmi. 2010)

  For those of you who are missing out on the daily 12+ SuppVersity Facebook News, because they haven't liked www.facebook.com/SuppVersity, yet. I will now publish it again - as a reference source, if you will.
• Milk a glucose uptake promoter that's more than the sum of its parts. In view of the fact that we have already two dairy related news in today's SuppVersity article, I decided to have another "milky news" in today's SuppVersity short news item. One all the milk-drinkers among the SuppVersity readers will cherish.
  
  Recently, Shirin Panahi and colleagues from the University of Toronto, the Mount Saint Vincent University and the University of Guelph published the results of a randomized, cross-over study that was conducted to prove / disprove the hypothesis that

  "[T]hat regulation of postprandial glycemia after milk consumption occurs through both insulin and insulin-independent actions due to interactions among its macronutrient components and energy content. The objective was to compare the effects of isovolumetric (500ml) beverages of whole milk (3.25% M.F.), each of its macronutrient components (protein, lactose and fat) and their combination (a simulated milk beverage) on postprandial glycemia, glucoregulatory and gastrointestinal hormones and gastric emptying in healthy young men" (Panahi. 2014).

  In the course of the study, the 12 young, male subjects consumed beverages containing 500 ml of whole milk (3.25% M.F.) (control), a simulated milk beverage based on milk macronutrients or milk protein (16g), lactose (24g) and milk fat (16g) in isolation.

  

  Table 2: Nutritional composition of the test meals | ^a Composition of each beverage as provided by
  the manufacturer; ^b amounts given are per 500ml serving. Paracetamol (1.5g), vanilla extract (1.2ml)
  and sucralose (0.02g) were added to all beverages (Panahi. 2014).

  What the researchers found was that both the whole and simulated milk had similar beneficial effects on blood glucose rise after their "meal" (drink), but as it turned out the simulated milk resulted in a significantly higher (41%) glucagon-like peptide-1 (GLP-1) production and lower (43%) ghrelin areas under the curve (AUC) than whole milk (P=.01 and P=.04, respectively).

  

  Figure 2: Glucose, insulin, c-peptite, rate of insulin secretion, GLP-1, PYY, CKK
  and ghrelin levels after the test "meals" expressed relative to the sum of the effects
  of the same amount of milk protein, lactose and fat (Panahi. 2014)

  Now, all that would hardly be newsworthy (at least not for regular SuppVersity readers, if the two samples, i.e. both the whole and simulated milk, didn't lower the glucose (P=.0005) levels more than predicted by the sum of AUCs for their components (see Figure 2)!

  "Adjusted for energy content, milks produced lower glucose and hormone responses than predicted from the sum of their components. The effect of protein/kcal on the AUCs was higher than fat/kcal for insulin, C-peptide, insulin secretion rate, GLP-1, CCK and paracetamol (P < .0001), but similar to lactose except for CCK and paracetamol, which were lower. The response in PYY and ghrelin was similar per unit of energy for each macronutrient" (Panahi. 2014).

  In other words: Milk is way more than the sum of it's parts. In that, the "regulation of postprandial glycemia after milk consumption occurs through both insulin and insulin-independent actions due to interactions among its macronutrient components and energy content to achieve lower postprandial glycemia than predicted from the sum of its components" (Panahi. 2014).

If you haven't read it, already, take a look at my rebuttal to the latest assault on milk | read more

Bottom line: Quite the "milky" short news, right? Well, I guess it may be worth topping off all these good news about dairy products with a bad one. The common "Internet wisdom" that raw milk could offset the problems of people with lactose intolerance is a myth.

According to a 2014 paper by Sarah Mummah et al. who tested this myth in 16 adults with self-reported lactose intolerance and lactose malabsorption confirmed by hydrogen (H2) breath testing, "raw milk fail[s] to reduce lactose malabsorption or lactose intolerance symptoms compared with pasteurized milk among adults positive for lactose malabsorption." (Mummah. 2014) The "raw milk can be consumed by anyone" anecdote does thus belong to the realms of scientifically unwarranted die-hard bro-science | Comment on Facebook!

References:

• Ehling, Stefan, and Todime M. Reddy. "Investigation of the Presence of β-Hydroxy-β-methylbutyric Acid and α-Hydroxyisocaproic Acid in Bovine Whole Milk and Fermented Dairy Products by a Validated Liquid Chromatography–Mass Spectrometry Method." Journal of agricultural and food chemistry 62.7 (2014): 1506-1511.
• Hulmi, Juha J., Christopher M. Lockwood, and Jeffrey R. Stout. "Review Effect of protein/essential amino acids and resistance training on skeletal muscle hypertrophy: A case for whey protein." (2010).
• Mummah, Sarah, et al. "Effect of Raw Milk on Lactose Intolerance: A Randomized Controlled Pilot Study." The Annals of Family Medicine 12.2 (2014): 134-141. 
• Panahi, Shirin, et al. "Mechanism of action of whole milk and its components on glycemic control in healthy young men." The Journal of nutritional biochemistry (2014).

Combinations that Work: HMB & Isometric Training for Lean Mass, Creatine & Powerlifting for Leaning Out and Carnitine & Bodybuilding for Powerlifting?

Image 1: Jacek Spychala - I must admit, I don't know if he was one of the subjects, but 38 of his colleagues from the Polish National Powerlifting Team were (powerlifting.pl)

As an athlete and even as a regular fitness enthusiast, you got to chose your training and supplementation modalities according to your professional or personal goals (in fact, the failure to do so is, in my mind, one of the main causes why so many trainees do not get the desired results at the gym). A very recent study from the Department of Combat Sports and Weightlifting at the Józef Pilsudski University School of Physical Education (I wish every University had such a department ;-) in Warsaw, Poland, sheds some light onto combinations which work, and combinations which don't... and trust me you will be surprised by the results of Dr. Marek Kruszewski's controlled intervention study (Kruszewski. 2011).

Kruszewski recruited recruited a total of 170 (! that alone is noteworthy !) subjects who participated in a three-tier placebo-controlled study on the effects dietary supplementation of l-carnitine, creatine and HMB combined with different modes of strength training (bodybuilding type circuit training, powerlifting and isometric training) had on muscle strength, lifting performance and body composition (for a graphical overview of the study design see figure 1).

Figure 1: Graphical illustration of the three tiers (l-carnitine, creatine, HMB), general information and detailed information on the exact exercise protocol of the isometric workout of the HMB group

Not only the sheer size of the study with active and placebo groups of ~30 previously untrained subjects, each, in the l-carnitine and HMB tier of the study are impressive, the participation of 38 powerlifters from the Polish National Team (cf. video of Daniel Grabowski, with a 2254lbs total) is, as well. If each group had received all three of the supplements subsequently and body composition had not been measured with an expensive but still not 100% accurate body impedance device, this study would have been the equivalent of the egg-laying-wool-milk-sow of the Natural Rythmicity for Maximum Fat & Minimal Muscle Loss episode of the Intermittent Thoughts, but I guess we cannot have it all ;-)

2g HMB + isometric training for lean muscle gains!

Image 2: HMB is getting
cheaper, lately

I thought, I'd give the most "exotic" training variety (isometric training) the advantage and tell you about the effects 2g of HMB per day (4 servings of 500mg; one with breakfast, one before, one after the workout and one in the evening; for 5 weeks = 20 training sessions) had on the strength performance and body composition of 69 previously untrained, strength trainees -  not only to raise the awareness that isometric contractions could be a valuable addition to everyones regime (something my friend Rob Regish also advocates in his Blueprint), but also because the effects observed in this tier of the study were, as Kruszewski points out, "[t]he most distinctive and desirable" ones:

Although this type of supplementation [HMB] was used in the group of subjects who trained using the isometric method, regarded as a training system not associated with increases in lean body mass (LBM), the obtained results indicate that HMB may also affect LBM. In view of the fact that LBM involves mainly muscles containing about 70% water, the demonstrated significant elevation of LBM accompanied by the reduced water content in the bodies of the examined competitors is difficult to explain.

Now, I've got you listening my iron-friends, don't I? Increased lean mass (+1.31kg), decreased (as the author points out, later) "presumably extracellular" water - sounds like it was coming from a competitive bodybuilder's "dry dreams", doesn't it? Well, the one thing that would be missing now, is a way to get rid of the fat - but wait, weren't there other supplements in the study, as well?

10g Creatine (+10g dextrose) + powerlifting for fat loss!

Image 3: Creatine monohydrate
for fat loss? That's a surprise.

Yes, there were, and believe it or not, not l-carnitine and circuit training, but creatine and powerlifting will shed the fat - even in elite level powerlifters! By continuing their regular (pyramid style, cf. figure 1) powerlifting training, the 16 power lifters from the Polish National Team, who received the 20g/day creatine + dextrose combination did not only improve their powerlifting performance by a statistically significant +15.6kg over the placebo group, they also and, as Kruszewski points out, "surprisingly" lost a significant amount of body fat in the course of the 20 training sessions they completed within the 5 week study period:

[...] the present results indicate that supplementation with this compound [creatine] led to a significant reduction in the fat content and increase in the water content of the organisms of powerlifters from the Polish National Team.

In view of the results, the author observed in the last group, the one which did a bodybuilding-type circuit training that was supplemented with 900mg of l-carnitine l-tartrate per day (cf. figure 1), I find it pretty amusing that according to Kruszwski the "effect of creatine may be much more far-reaching than that indicated in the manufacturers’ leaflets", which is something, he certainly would not say of l-carnitine.

900mg l-carnitine l-tartrate + "bodybuilding-type" circuit training for powerlifting? 

Image 4: L-carnitine alone will not transform your physique like this magic mirror - no matter what the advertisement leaflet in the latest muscle mag says ;-)

The results in the l-carnitine supplemented group (3x300mg l-carnitine l-tartrate) were mixed. While the previously untrained subjects obviously gained strength in the course of the 15 workouts they performed in the 5 week study period, there were huge intergroup differences - meaning that a few subjects appeared to benefit from carnitine, while the majority didn't. Moreover, fat loss or beneficial changes of body composition, which is what l-carnitine is marketed for, were completely absent in the l-carnitine group. And while the training intensity was pretty low (although the trainees had to perform the 3rd of their three training circles to complete failure) this does not really surprise me, as the "fat burning" effect of oral carnitine supplementation has been debunked by more than a dozen well-designed studies, so that you better follow Kruszewski's advice and "treat advertisements of this compound [l-carnitine] with reserve" ;-) He goes on to explain that...

[...i]t is possible that individuals with inherited or acquired L-carnitine deficiency manifested by increased deposition of fat in the body may benefit from such supplementation and improve their body composition by consuming appropriate amounts of this substance accompanied by proper (predominantly aerobic) exercising. However, additional L-carnitine supplementation in individuals with normal production and concentration of this substance in the body is superfluous.

On the other hand, Kruszewski admits that despite the absence of significant improvements in muscle torque, the powerlifting performance of the subjects in the l-carnitine group increased statistically significantly more than the one in the placebo group (+13.7kg) which is ...

surprising in view of the fact that such an effect [increase in powerlifting performance] of L-carnitine has very rarely been reported and emphasized.

He goes on to suggest that these improvements may be related to l-carnitines impact "on the general physical fitness of the organism". Yet, whatever the reasons may be - out of this triumvirate, l-carnitine would certainly be the least effective addition to your regimen - whatever your goals may be.

Isometric training and HMB supplementation, on the other hand, emerge as as surprise winner. With statistically significant (+17.7kg) increases in power-lifting performance, significant increases in muscle torque, and a +1,31kg increase in body mass (predominantly lean muscle) that was accompanied by a likewise significant reduction in extracellular water, it may be a good idea to take advantage of the falling HMB prices (buy in bulk!) and to incorporate some isometric exercises into your workout regimen ... what do you say?

Intermittent Thoughts On Intermittent Fasting - AMPK II/III: Leucine, HMB and a Glimpse on Other AMPK Modulators

Image 1: You pick a health, diet or diabetes supplement and I find the study that shows that in one way or another its effect is related to AMPK ;-)

I ended yesterday's installment of the Intermittent Thoughts on Intermittent Fasting Series on a pretty bold statement about the benefits of preworkout BCAA supplementation that would, at first sight, contradict common sense, or rather what common sense would dictate based on all you have read about the beneficial effects of BCAA supplementation on mTOR-related muscle protein synthesis (MPS) and the complementarity of mTOR and AMPK as regulators of anabolic (e.g. MPS, adipogensis ,etc.) and non-anabolic "scraping, rebuilding, recycling and repairing" processes. Since, after all, Bomb Jack, who posted a comment on last weeks installment of this series, is right: It would be logical that supplementation with BCAAs (he mentions HMB specifically) during the fast should result in dephosphorylation (~deactivation) of AMPK and thus negate its desirable effect on (metabolic) health.

And in fact, in the Wilson study I wrote about on Saturday the postprandial increase in AMPK phosphorylation, was blunted by the provision of carbohydrates, leucine or a combination of both (cf. yesterday's news) and you would assume that HMB supplementation would do the same, but the latter is - at least for chronic supplementation with low amounts (320mg/kg in rats ~ 52mg/kg in humans) of HMB - not the case (Pimentel. 2011), as the data I plotted in figure 1 clearly shows:

Figure 1: Effect one month of saline (control) or 80mg/day HMB on mTOR and AMPK phosphorylation and GLUT-4 expression in extensor digitorum longus (EDL) muscle of rats (Pimentel. 2011).

In the Pimentel study, there was, if anything, a non-significant increase in the AMPK and its purported downstream effect on GLUT-4 mediated glucose uptake  - both of which common sense would have told us to be compromised by HMB supplementation. While the lack of information on the "timing" or, more specifically, the interval between the last feeding and the intragastric administration (gavage) of 320 mg/kg body weight of HMB is a drawback in view of the significance of these results in an intermittent fasting context, rats usually eat at night and thus the administration of the 80mg of HMB (the rats weighed only 250g) "daily at the same time (during the light period)" will probably have coincided with a "fasting" period.

How can we explain that mTOR expression increased, while AMPK remained constant?

Are the different result a consequence of the metabolic magic of HMB? Well, before we analyze that in detail, there is another significant difference, we have to account for - in fact, a much more obvious one, which the amount of amino acids the rats were given in the Wilson and the Pimentel study, respectively (cf. figure 2).

Figure 2: Dosage, not type of supplement would be the most probable explanation for the different effects of leucine and HMB supplementation on AMPK phosphorylation in the Wilson vs. the Pimentol study.

I hope you did not already forget that, the main function of AMPK is to prevent that your cells run out of fuel or, to be precise, to avoid the ratio of "used" energy ADP and AMP (adenosine di- and monophospate) to ATP (adenosine triphospate) to continue to rise beyond a tolerable level. I further assume that you will be familiar with the fact that branched-chain amino acids bypass oxidation in the liver and thus become readily available energy sources for skeletal muscle (Renny. 2011). Now, if you put one and one together the answer seems pretty obvious: If the dosage of amino acids is sufficient (remember that those 270mg leucine are 4x more leucine than the the rats in the Wilson study got for "breakfast") to restore ATP levels to "appropriate" levels, the decrease in the ADP/ATP ratio will allow part of the AMP-activated protein kinase to be dephosphorylated.

According to our current understanding, BCAAs in general and leucine in particular trigger the ATP related decrease in AMPK and the complementary increase in mTOR by two distinct pathways, of which Tokunaga et al. write (Tokunaga. 2004)

[...]leucine stimulates p70α phosphorylation via mTOR pathway, in part, by serving both as a mitochondrial fuel through oxidative carboxylation and an allosteric activation of glutamate dehydrogenase. This hypothesis may support an idea in which leucine modulates mTOR function, in part by regulating mitochondrial function and AMPK.

In plain English: Leucine increases ATP when it is "burned" as fuel and it docks directly to the the non-active site of glutamate dihydrogenase enzyme and thusly increases the conversion of glutamate to alpha-ketoglutarate which in turn can be fed into the citric cycle to ultimately produce ATP.

Is it all about (cellular) energy ...

Figure 3: AMPK phosphorylation in Escherichia coli at different ADP/ATP ratios (data adapted from Xiao. 2011)

In April 2011 Xiao et al. published a study in Nature with some interesting quantitative data on the ADP/ATP ratio, on the one hand, the phosphorylation status of AMPK, on the other (Xiao. 2011). As my plot of the data in figure 3 shows, with increasing ATP levels (at constant ADP levels of 30µM) the phosphorylation of AMP-activated protein kinase in Escherichia coli BL21 cells declines by roughly -20% from 44% at a 30/0 ADP/ATP ratio to 22% at a 30/800 ADP/ATP ratio.

Yet, although these results would confirm the hypothesis that the main reason for the discrepancy is dose, or rather, energy related, and each and every nutrient that could potentially raise ATP levels, would eventually decrease AMPK, this still does not explain the increase in mTOR Pimentel et al. observed, despite (statistically non-significant) increases in AMPK.

... or is there a place for the "magic" of HMB?

As you probably know, beta-hydroxy-beta-methylbutyrat (HMB) is an oxidation product of leucine and / or its keto-acid alpha-ketoisocaproate (KIC) (Koevering. 1992). In 1998 Lembert et al. found that even KIC is not a direct substrate for ATP production, instead "KIC must transaminate with glutamate or glutamine to yield alpha-ketoglutarate and leucine" (Lembert. 1998). We may thus assume that similarly HMB cannot be used (directly) to restore cellular ATP pools. Moreover, HMB is thought to be the second (non-energetic) pathway by which leucine acts on protein synthesis / breakdown. According to a 2011 review of the literature by Zanchi et al. (Zanchi. 2011)

Nissen et al. (1996) suggested that HMB or some other metabolite (since there is no specific inhibitor to BCAT) is the main component responsible for the anti-catabolic effects of HMB because when adopting inhibitors of BCAA transamination, the only BCAA capable of anti-proteolytic effects is leucine, which undergoes a process capable of generating HMB (Slater and Jenkins 2000). Such effects were not observed when other BCAAs were tested (isoleucine and valine), suggesting that HMB or some metabolite may be the key element in promoting the [anticatabolic] effects.

When usually 5% of the dietary leucine is metabolized into HMB (Wilson. 2008), and these 5% are responsible for the non-ATP dependent effects on phosphorylation of mTOR, p70^S6k, and 4E-BP1 of leucine (Eley. 2007), it is no wonder that chronic intake of 80mg of HMB did stimulate mTOR in the absence of increased ATP levels (which would obviously have led to a decrease in AMPK expression that was not present in the Pimentol study), while 270mg leucine, yielding only 13.5mg HMB, did not stimulate mTOR, but was (ab-)used as a substrate to increase cellular ATP levels, thusly reduced AMPK levels and increased protein anabolism - different pathways, similar results: an increase in net protein synthesis.

Figure 4: Simplified illustration of the two distinct pathways by which leucine can work its muscle protein synthetic (MPS) magic and a hint on the compensatory (/) / amplifying (+) effects of exercise.

There is however, a third major pathway to the metabolic effects that are brought about by common intermittent fasting programs and this third player makes things even more complicated (cf. figure 4) - it's exercise! You probably remember from yesterday's installment that

1. during exercise in the fasted state temporarily AMPK increases and the energetically costly muscle protein synthesis (MPS) is reduced, while
2. after exercise (regardless of whether it was performed fasted or not, cf. "Glycogen-Free Growth") muscle protein synthesis increases due to an exercise-induced stimulation of the mTOR protein synthetic cascade

Before we dig deeper into this modulatory effects of different modes of exercise in the next installment of the Intermittent Thoughts on Intermittent Fasting, however, I want to conclude today's thoughts with a preliminary list of supplements / medications that have been shown to modulate the phosphorylation state of 5' AMP-activated protein kinase.

Image 2: If you insist on trying HMB, don't be stupid and buy a capped products, the prices for bulk HMB powder have lately been crushed - a major European carrier, for example, sells 250g at <13€ atm; HMB is thus cheaper than BCAAs, which cost 16Euros in the small 250g pack - did you hear me say that even 13€ is too much, no - you must be mistaken ;-)

"Should you prefer HMB over leucine as a dietary supplement to promote lean mass gains and prevent muscle loss during the fast?" I assume this is a question many of you will now be pondering about. My answer to this question would be "NO!" Firstly, if you are no construction worker or pursue a similar physically demanding profession, the fear of losing muscle (which is different from "feeling flat", my bodybuilding friends ;-) during a ~16h fast is hilarious, which means that BCAA, Leucine or HMB supplementation, while you sitting fasted at your desk in the office is simply unwarranted. Secondly, when you are exercising the increased energy demand will negate / compensate the negative effect the increase in ATP has on AMPK activity. And thus, thirdly, a large bolus of leucine (or a complete BCAA or EAA product) taken pre-workout will not only ward off proteolysis (as HMB would do) it will also provide the necessary energy to train harder and thus help to increase the exercise induced stimulus on protein synthesis.

All that and the absence of conclusive scientific evidence that would demonstrate the superiority of HMB supplementation over the provision of adequately dosed BCAA or EAA mixtures (it stands to reason that you cannot compare 3g of HMB to 3g of BCAA) are arguments against the use of β-Hydroxy β-methylbutyric acid. If you wanted to try it, anyway (and have no problem swallowing a powder that tastes like poison), the prices for bulk-powders have gone through the floor, lately ;-)

How to modulate AMPK "artificially" -  supplements, medications, hormones and more

In view of the fact, that the discussion of the effects of leucine (BCAAs and HMB) alone took much longer than I had expected and this whole episode took a different turn than I would have expected, the following list is more a preliminary overview than a comprehensive explanation of the effects of various supplements, medications, hormones and hormone-like substances on the AMPK. The latter will follow, as promised, but for today, you will have to content yourselves with what I would like to call a sneak peak on the AMPK-mTOR modulation handbook of which I hope that it will be one of the outcomes of all the past and future work that is going into this series ;-)

AMPK promoters:

• Adiponectin (Yamauchi. 2002; Handy. 2010; Iwabu. 2010)
• Alpha lipoic acid (Lee. 2005; Wang. 2010; Packer. 2011)
• Artemisia sacrorum Ledeb (Yuan. 2010)
• Aspirin (Sung. 2011)
• Astragalus (Zhou. 2009)
• Berberine (Ma. 2011)
• Brain-derived neurotrophic factor (Matthews. 2009)
• Caffeine (Jensen. 2007; Spirydopulos. 2008; Egava. 2009) 
• Capsaicin (Kim. 2010)
• Catechins / green tea (Huang. 2009; Murase. 2009; Reiter. 2010)
• Chromium (Wang. 2009)
• Ciliary neurotrophic factor (CNTF) (Watt. 2006)
• Cinnamon (Huang. 2011)
• Conjugated Linolic Acid (CLA) (HSU. 2011)
• Coptidis Rhizoma (CR), the dried rhizomes of Asian herbs (Egawa. 2011) 
• Cordiceps sinensis (Wong. 2010)
• Creatine (Ceddia. 2004)
• Curcumin (Kim. 2010)
• DHA (Jing. 2011)
• Ecklonia Cava (Kim. 2010)
• Garlic (Lee. 2011)
• Ginseng (Juang. 2010)
• Glucosamine (Kong. 2009)
• Grape seed extract (Meeprom. 2011)
• Hibiscus sabdariffa extract (Yang. 2010)
• Interleukin-6 (Kelly. 2009)
• Kidney bean extract (Lee. 2009)
• Malva verticallata seeds (Jeong. 2011)
• Metformin (Zhou. 2001; Freyer. 2002; Ohira. 2009)
• Mulberry extract (Tsuduki. 2009)
• Nicotine (Cheng. 2007)
• Prostaglandin E2 (Zhu. 2011) 
• Pu-erh tea (Way. 2009) 
• Quercitin (Jung. 2010)
• Raishi Mushroom (Lane. 2011)
• Resveratrol (Fullerton. 2010; Lin. 2010; Breen. 2008)
• Tiozolidinediones (diabetes meds. like rosiglitazone) (Freyer. 2002; LeBrasseur. 2005; Yang. 2011) 
• Vanadium (Hwang. 2011)

I still have two things to add to this list, firstly, this list is the result of a VERY cursory and 100% random search and is not even intended to be complete (at this time ;-). The intention (at least for in this installment) is to show you that an overwhelmingly large percentage of purported health supplements, diabetes and obesity treatments work via the AMPK pathway. And, secondly, I decided to limit the references to 1-3 per compound, even if in cases such as Metformin, ALA & Co the number of relevant studies is probably >500. Therefore you better consider the given references as evidence that I did not make up any associations between compound X and AMPK phosphorylation - and, if you want to know more before the release of the next installment, I suggest you go to PubMed and enter the respective keywords and do some digging on your own (your SuppVersity homework of the day - so to say ;-)

I hope you do not mind that I did not manage to tackle the effects of sleep and exercise in this installment, as I had originally intended. It is, after all, the central characteristic of this series that I sit down in front of the computer and start thinking at point "A", then I dig, here, get distracted there and follow up on "A1" to "A743", so that the output is by no means as structured and straight forward as my lectures and seminars or my SuppVersity blogposts on isolated topics... so, I can only hope that you enjoyed the turn this installment took (at best, because you learned something new) and in the unfortunate case that you did not enjoy what you have just read, you can at least look forward to the next episode of the Intermittent Thoughts on Intermittent Fasting Series ;-)

Use HMB to Improve Your "Muscle Quality", Training to Build Muscle and Training + HMB to Cut Body Fat. It Works For the Elderly Will It Also Work for You?

This is Ernestine Shepherd; and while Ernestine is not one of the study subjects she would qualify. After all, she is 74. And she is also something else: An example of the anti-aging effects of life-long exercise and sensible nutrition.

HMB has gotten back to the limelight lately. Many scientists are currently working on advanced preparations with increased or faster absorption rates. A soon-to-be-published study in the Journal of Experimental Gerontology does however suggest that the latter may - at least for some basic and certainly non-negligible effects in the aging muscle and adipose tissue - not even be necessary. For these purposes the good old (and disgustingly tasting) CaHMB powder us Europeans can get for cheap at every street corner appears tow work quite fine.

In a randomized controlled study, the Jeffrey R. Strout and his colleages from the University of Central, the University of North Carolina, the Georgia Southern University, the United States Sports Acadamy, and the University of Tampa, observed that the 3g of "good old" calcium-β-hydroxy-β-methylbutyrate (CaHMB) works just fine to increase leg strength and muscle quality in >65yr old subjects.

To be able to evaluate the effects of HMB alone and in combination with strength training, the scientists divided the study into two main phases:

• Phase I consisted of two non-exercise (NE) groups: (a) ad libitum diet plus placebo (NEPLA) and (b) ad libitum diet plus CaHMB (NEHMB). 
• Phase II consisted of two resistance exercise (RE) groups: (a) ad libitum diet plus placebo and resistance exercise (REPLA) and (b) ad libitum diet plus CaHMB and resistance exercise (REHMB). 

The study evaluation period for each participant in Phases I and II was 24 weeks. Testing was performed at week 0 (pre-test), 12 weeks (mid-test), and 24 weeks (post-test), and consisted of body composition (the scientists used reliable DXA scans to assess the lean mass and body fat levels), muscle strength, functional movement, three-day dietary recall, blood markers, and urinalysis for HMB consumption.
 
2x1.5g + 4g carbs did the trick

Muscle quality (MQ) - what is that? "Muscle quality (MQ) was calculated as muscle strength relative to muscle mass. MQ has been used and described previously as an indicaor of muscle function (Lynch et al., 1999; Tracy et al., 1999)." (Strout. 2013) Being a measure of strength relative to muscle mass, MQ is considered a predictor of health status, mortality and a better indicator of muscle function than strength alone (spec. the hilarious grip strength measures you see in many studies in geriatric journals).

The supplement had to be consumed with a non-alcoholic drink at least 2x per day. In addition to the HMB or placebo powder it contained an additional 4g of carbs (I am mentioning this, because it cannot be excluded that this had a minimal effect on the absorption or metabolism of HMB). The resistance training sessions (RE) in the 2nd phase of the study were performed three times per week. The volume of the training sessions (number of sets per exercise per week) was as follows (quoting directly from Strout. 2013):

• week 1 was pre-testing only, 
• weeks 2 and 3 included one set per exercise, 
• week 4 was two sets, 
• weeks 5–10 were three sets, 
• week 11 was one or two sets, 
• week 12 was mid-testing only, 

• weeks 13 and 14 were one set, 
• week 15 was two sets, 
• weeks 16–22 were three sets, 
• week 23 was one or two sets, and week 24 was post-testing, only. 

During each training session, all participants completed one to three sets of 8–12 repetitions for each exercise.

Exercises included the bench press, lat pulldown, bilateral leg press, hack squat, and bilateral leg extension. The subjects rested for 2-5min between the exercises and used a classic linear progression (+2-4kg), whenever they felt comfortable performing their exercises with 12 reps at their previous training weight.

Figure 1: Changes in body composition in response to phase 1 (no exercise) and phase 2 (resistance training) of the 2x 12 week intervention study (Strout. 2013)

If you look at the data in figure 1 you will see that the major driving force behind the changes in body composition was not the supplementation regimen. As Strout et al. point out, both HMB alone, as well as its combination with resistance training did however yield statistically significant changes in the muscular architecture of the 72-73 (+/-1) year old subjects (for an explanation of the parameter "muscle quality" see info-box above):

The fat loss certainly reminds me of the recent leucine + B6 study

"Phase I of the current study demonstrated that prolonged supplementation with CaHMB [alone] improved total lean mass (LM), strength, function and MQ without resistance exercise.

In addition, the progressive, high-intensity resistance training protocol used in Phase II resulted in increased LM, strength, and MQ, with or without CaHMB.

Moreover, the CaHMB intervention in Phase II resulted in a significant decreased total fat mass along with the increased total lean mass and arm MQ from the training."

What I consider particularly interesting, here, is the statistically significant increase in fat loss, which is certainly not the first thing you may be thinking about, when it comes to HMB supplementation. In a way this reminds me of the astonishing effects Zemel et al. observed in their recently published Leucine + B6 study (see corresponding SuppVersity article from August 31) and would support the notion that leucine and/or its metabolite HMB increase the oxidative capacity of skeletal muscle - at least in situations of increased cellular stress (obesity in the Zemel study or training in the study at hand; see as well "Leucine + Resveratrol - Synergistic Sirtuin Boosters: +118% Fatty Acid Oxidation, 60% Increase In Muscular Glucose Uptake, -30% Visceral Fat & More - To Good to be True? | read more"). In this context, Strout et al. write:

"One interesting finding regarding the CaHMB treatment in the present study was its effect on fat mass, which was consistent with Vukovich et al. (2001). CaHMB alone did not cause fat loss. However, resistance training with or without CaHMB resulted in a significant loss of fat mass at week 12, whereas only the CaHMB group was able to further the reduction in fat mass at week 24." (Strout. 2013)

They then make a questionable statement about how "resistance exercise is not thought to be a potent stimulus for total body fat loss", but get back on track when they add:

"[...] recent evidence suggested that CaHMB supplementation improved fatty acid oxidation, adenosine monophosphate kinase (AMPK), and Sirt1 and Sirt3 activity in adipocytes and in muscle cells (Bruckbauer. 2012). Collectively, these proteins act to improve mitochondrial biogenesis, fat oxidation, and energy metabolism." (Strout. 2013)

This would support my own hypothesis that the fat loss is mainly a function of mitrochondrial activity / increases in mitochondrial capacity. And while it has to be determined whether similar effects can be observed in non-muscle cells, even he local improvement of mitochondrial biogenesis would have beneficial downstream effects on whole body metabolism - including the brain!

---

If you want to learn more about the usefulness of HMB, I suggest take (another) look at my article about the results of a 2012 dissertation (read more)! And a previous report in the short news about the difference between leucine & HMB (read more)

Bottom line: Smart best-agers are good advised to make sure to get their daily dose of good ol' Calcium-HMB: I guess, I could actually leave it with that if there were not a couple of questions left to address:

1. Will these effects occur in individuals on "high" (=2xRDA) protein diets, as well?
2. Will they add to the beneficial effects a regular whey protein has to offer?
3. Is age critical to benefit or are we going to see the same, improved or smaller effects in younger individuals, as well?

While it really seems that we have been missing out on a highly useful supplement that has been available for years, there is still some research to be done, before these questions can be answered with the necessary confidence.

A note on protein requirements in the elderly: Did you know that the current recommended protein intake for the elderly is 0.6g/kg body mass and that Campbell et al. were able to show that at least 1.0g/kg is needed simply to maintain a normal nitrogen balance ? No, well now that you know the 1.1g/kg baseline protein intake in the study at hand tell you what kind of scenario we are talking about - one of protein adequacy, at best!

In my humble opinion the latter is specifically true with respect to questions (1) and (2) as corresponding data is hitherto simply non-existent. So we are hard pressed to tell whether you can achieve identical or at least similar body recompositioning effects by simply adding a whey protein shake or protein bar that is not 80% sugar to the diets of our unfortunately protein-underfed "best agers".

On the other hand, previous studies in trained athletes, as well as the user feedback due to which HMB more or less disappeared from the market would suggest that this definitely is the case for younger folks, meaning the usefulness of regular, slow digested calcium HMB in the context of an already highly optimized training and nutritional regimen in people who do not have to fight the age-induced continuant catabolism is more than questionable.

References:

• Bruckbauer A, Zemel MB, Thorpe T, Akula MR, Stuckey AC, Osborne D, Martin EB, Kennel S, Wall JS. Synergistic effects of leucine and resveratrol on insulin sensitivity and fat metabolism in adipocytes and mice. Nutr Metab (Lond). 2012 Aug 22;9(1):77.
• Stout JR, Smith-Ryan AE, Fukuda DH, Kendall KL, Moon JR, Hoffman JR, Wilson JM, Oliver JS, Mustad VA. Effect of calcium β-hydroxy-β-methylbutyrate (CaHMB) with and without resistance training in men and women 65+yrs: A randomized, double-blind pilot trial. Exp Gerontol. 2013 Aug 24.
• Vukovich MD, Stubbs NB, Bohlken RM. Body composition in 70-year-old adults responds to dietary beta-hydroxy-beta-methylbutyrate similarly to that of young adults. J Nutr. 2001 Jul;131(7):2049-52.

Leucine + Resveratrol - Synergistic Sirtuin Boosters: +118% Fatty Acid Oxidation, 60% Increase In Muscular Glucose Uptake, -30% Visceral Fat & More - To Good to be True?

Image 1: Can you really team up leucine (or HMB) and resveratrol to make tired mitochondria get a move on? NuSirt Sciences says "YES!" And in the dish and rodents it's actually already working.

What happens if you marry a well-known AMPK promoter and exercise mimetic, with an even more prominent exercise adjuvant and nutritional mTOR booster? Will they neutralize each other? Think about it.... ok, now gimme your answer: What happens if you put resveratrol and leucine together? At first it does not really make sense, does it? Right, it doesn't, at least not unless you follow the same train of thought, the researchers from NuSirt Sciences. NuSirt? That rings a bell, hah? Yeah those were the guys who did a study on their 250mg leucine + 30mg vitamin B6 proprietary blend NuFit (see "Testosterone - 12% Drop /W 75g Glucose? Fat Loss - Adzuki, Leucine + B6 or HiMaize & More") and actually, the leucine + resveratrol combination is sort of a spin-off of this initial research.

If you put Sirt1 & Sirt1 together, it suddenly makes sense!

In their latest study (and you bet a future product!) Bruckbauer et al. build on their previous research on the agonistic effects HMB, alpha-KIC or leucine have on skeletal muscle Sirt-1 activity (Bruckbauer. 2011) and rationalize that it seems legit to combine one Sirtuin portein promoter with another one in order to achieve an even more pronounced effect - makes sense, right? Resveratrol the proven AMPK-promoter and igniter of the longevity, gene transcription, cell survival and apoptosis regulating Sir2 proteins (=sirtuins) and leucine the mTOR promoting and, as of late, proven Sirt1 agonist, they could actually form a synergistic duo for fat oxidation, glucose management, the reduction of oxidative stress and inflammation and even longevity!

Figure 1: Effects on sirtuin & AMPK expression in muscle and fat cells upon incubation with leucine, HMB and resveratrol and the respective combinations (left) and effects fatty acid oxidation in isolated rat skeletal muscle upon incubation in low and high glucose conditions (data based on Bruckbauer. 2012)

Now, aside from Sirt1, which is mainly expressed in the nucleus of a cell, another one of the Sir2 proteins, Sirt3, which is expressed predominantly in the mitochondria has as of late gathered quite some attention, as mitochondrial dys- or malfunction is one, if not the common denominator of many of the pathological features of the metabolic and neuro-endocrine ailments the Western diabesity society is suffering from: insulin resistance, type II diabetes, Alzheimer's , you name them! No wonder the NuSirt guys (and girls) are striving to find a marketable way to set them both in full gear and if you take a closer look at the data in figure 1 their initially counter-intuitive approach to bath muscle and fat cells in resveratrol  + HMB / leucine solutions yields impressive results:

• resveratrol, leucine and HMB, alone, exerted only weak independent effects on Sirt1, Sirt 3 and AMPK
• resveratrol and leucine or HMB, combined, yielded Sirt1 and Sirt3 activity increases in the ~50% range (p < 0.05) and AMPK increases of +42% and +55% (p < 0.03); particularly noteworthy are the ~125-175% increases (p < 0.02) muscle cells (remember: Sirt3 is expressed in the mitochondria!)
• the ensuing increases in fatty acid oxidation in incubated muscle cells reached statistical significance in the presence of low (5 mM) glucose levels, only, when and 5 µM HMB or  0.5 mM leucine were co-incubated with 200 nM (~18%; p < 0.05), in the high glucose condition, however, all treatments broad about significant increases in fatty acid oxidation, of which those in the leucine- and HMB-resveratrol combination treatments were the most pronounced (118% and 91% stimulation, respectively; p < 0.005)

Especially the last finding, i.e. the increase in fatty acid oxidation in an in-vitro condition that resembles the hyperglycemic state the average type II diabetic who is not popping tons of metformin and/or injecting insulin is constantly in, makes these results particularly interesting, as it appears as if a "non-pharmacological" (what by the way is "pharmacological" and what isn't?) solution to the diabesity problem could already be hidden on the shelves of your GNC right next door (I assume they carry leucine and resveratrol products ;-)!

Outside of the box... ahh, I mean, ... the petri dish!

In view of the fact that 75% of the in-vitro high performers suck in the rodent model already and of those another 75% don't work in human trials you will be pleased to hear that NuScirt Sciences' resveratrol + leucine / HMB combination has already overcome the first of these hurdles: At least in DIO (diet-induced-obese) rodents who on a 6-week high fat diet regimen, the combination works.

Figure 2: Weight gain, visceral adipose volume, PET measured palmitate uptake, respiratory rate (lower levels = higher relative fat oxidation), heat production relative to body weight, food intake; all value expressed relative to DIO mice who were maintained on an unsupplemented control diet (data based on Bruckbauer. 2012)

Now, it's not as if the rodents would have made it to the Mr Olympia stage, but if you take a closer look at the pattern that's emerging here, it's quite clear that the sirtuin booster does its job in this rodent model. Aside from its ameliorative effect on weight gain, the combination of resveratrol and leucine, led to statistically significant improvements in glucose management and improvements in inflammatory markers (including the anti-inflammatory adipokine adiponectin, see figure 2).

Figure 2: Glucose, insulin and HOMA IR levels, muscular glucose uptake (left), C-reactive protein , IL-6, MCP-1 and adiponectin (right) ; all value expressed relative to DIO mice who were maintained on an unsupplemented control diet (data based on Bruckbauer. 2012)

Most importantly, however it effectively cut through the exuberant amount of visceral adipose tissue (>30% reduction), ramped up the palmitate (fatty acid) uptake, oxidation and heat production (=thermogenesis). Despite all these metabolic improvements which took place in the absence of a simple reduction in food intake, there are still a couple of things left to be desired:

What are the human equivalent doses, here? Since I know you would be asking I did the math for you and you will be pleasantly surprised (HED for 80kg humans)

• 12.5mg resv. = 9mg
• 225mg resv. = 136mg
• 2g HMB = 1.1-1.4g
• 10g HMB = 7.2g
• 24g leucine = 14.3g

I am well aware that it must look as if I had the typical poor arithmetic abilities of the average physicist who has totally forgotten how to calculate using figures instead of letters, but the reason for the discrepancies is that I calculated the exact HEDs based on body weight and food intake for each of the groups.

1. Supplementation with the respective human equivalent doses should yield the same astonishing results in humans as it did in the diet-induced obese mice.
2. The protocol should have effects not just in morbidly obese diabetic human beings, but also in overweight and ideally even lean individuals.
3. The supp must work if you don't put it into the chow, but pop it in separate doses (e.g. 3x/day) as a capsule or tablet.

The good news however is that if 1-3 apply, you could start benefiting from this "super supplement" right now! After all, the resveratrol dose of 12.5mg per kilogram of chow (the mice in the study did not consume more than max. 4g(!) per day) is so low that the 10g package I just saw for 20$ over at the webshop of a major bulk supplier would last you literally forever ...

Unfortunately, this is exactly why I don't believe that LeuResSirt, or whatever other stupid name the final product will be given, is going to work - I mean, come on, you can't tell me that there are not already people out there who get 15-20g of leucine everyday and pop resveratrol in 100x the necessary dose of 8-9mg everyday!? And did they turn into a beast, become fast-food resistant or lose fat magically? What? Yeah... that must be Phil Heath secret, right... how come I did not realize that before? ;-)

Bottom line: Regardless of the probably justified skepticism, I will still keep you posted on whether or not NuSirt knocks out another incredible (in the literal sense) human study like the one on NuFit (see "Testosterone - 12% Drop /W 75g Glucose? Fat Loss - Adzuki, Leucine + B6 or HiMaize & More"). So stay tuned, you all know that no supplement will ever more ergogenic than your daily dose of SuppVersity news!

References:

• Bruckbauer A, Zemel MB. Effects of dairy consumption on SIRT1 and mitochondrial biogenesis in adipocytes and muscle cells. Nutr Metab (Lond). 2011 Dec 20;8:91.
• Bruckbauer A, Zemel MB, Thorpe T, Akula MR, Stuckey AC, Osborne D, Martin EB, Kennel S, Wall JS. Synergistic effects of leucine and resveratrol on insulin sensitivity and fat metabolism in adipocytes and mice. Nutr Metab (Lond). 2012 Aug 22;9(1):77.