Better Sip Your Beta Alanine: Decreased Urinary Excretion from Time Released Beta-Alanine Formula.

Image 1: Tabbing or cabbing, or just washing it down with some water - what is the best way to take your beta alanine?

If you have been following the supplement scene for quite some time now, you will probably remember headlines such as "Beta Alanine, the next creatine!"... well, the hype which was deliberately fueled by the supp-companies, who realized that the price umbrella on creatine was shriveling, has abated and yet, beta alanine and, of course, creatine are both still there. Compared to the number of studies on creatine monohodrate, which were and still are published on almost a monthly basis, the science on beta alanine and most importantly its mechanism of action is however pretty skinny. I am thus happy to share with you a few interesting findings from two recently published studies - one today, the other tomorrow ;-)

The more it tingles the less it works... !?

Despite the fact that I personally like the awkward feeling you get when you take tons of beta alanine, I have always suspected that the "tingling" sensation - whatever its underlying reasons may be - is a very unsatisfactory indicator of whether the supplement "works" or not. After all, there is no physiological reason why the intended recombination of beta alanine + histidine to carnosine and the storage of the latter inside of your muscle tissues would go hand in hand with a "pins and needles" kind of flush. I was thus not surprised to see that Jacques Décombaz and his collegues from the Nestlé Research Center in Lausanne, Switzerland were able to show that ingestion of a "time-released" beta alanine tablet (2x800mg) did not only lead to statistically significant reductions in paraesthesia, but did also reduce the urinary excretion of the carnosine precursor (Décombaz. 2011).

Figure 1: Beta alanine (BA) serum values in µmol/L in the 6h after ingestion of 1.6 g of BA in solution or as time-released tablet (2x800mg); small graph: area under the curve (data based on Décombaz. 2011)

As you can see in figure 1, the time-released formulation avoids the rapid increase in beta alanine serum levels (solution: Cmax=248.2µmol/L; tablet: Cmax=81.9) Décombaz et al. observed with a standard solution of 1.6g beta alanine (Carnosyn TM) in aequeous solution.

Figure 2: Urinary beta alanine excretion (in µmol) in 11 healthy volunteers 0-2h and 2-6h after ingestion of 1.6 g of BA in solution or as time-released tablet (2x800mg); small graph: degree of retention (in % of intake) calculated based on urinary excretion (data based on Décombaz. 2011)

And although the area under the serum BA curve may be slightly smaller (AUC; figure 1, right), a calculation based on the decreased 6h urinary excretion in the 11 healthy caucasian volunteers (5 women, 6 men) who consumed the time-released preparation (cf. figure 2) reveals that the tissue retention from the tablet formulation was still 2.6% greater. Within the given standard deviations of 0.9% (tablet) and 2.1% (solution), I would yet be very surprised if this would actually make a practical difference as far as the ergogenic effects of beta alanine are concerned.

Figure 3: Topography of b-alanine-induced sensations. Data shown are the maximal reported values of the body
surface sensitive score (directly from Décombaz. 2011)

Of greater practical relevance is thusly the data on the incidence of "side effects" (did I mention that I like the tingling ;-), which - as the cute graphic in figure 3 goes to show - were significantly ameliorated when the subjects ingested their beta alanine in form of the hydroxypropyl methylcellulose, stearic acid, magnesium stearate, and silicon dioxide containing tablet.

... and why does it tingle? We still don't know!

What I personally do yet find more interesting than the reductions in sensory "side effects" are the speculations the scientists make as far as the underlying physiological reasons for the occurrence of the "pins and needles" (this was the prevailing description of the symptoms the study participants used) are concerned:

There are at least five recognized receptor sites for bA and the mechanism responsible for the sensitization of nociceptive neurons has not been unequivocally clarified [...] candidates include (a) bA-activated strychnine-sensitive glycine receptor sites, in association with glutamate sensitive N-methyl-D-aspartate receptors in the brain and the central nervous system, and (b) the mas-related gene family of G protein-coupled receptors, in dorsal root ganglia neurons ending in the skin, which are triggered by interactions with specific ligands such as bA.

While option b) sounds relatively harmless, option a) and previous studies reporting profound modulatory effects on brain neurotransmitter levels (esp. serotonin, cf. Murakami. 2010) keep me wondering, if beta alanine does not have more (and potentially harmful) side-effects than the minor paraesthesia.

So, in essence, we still don't know what it is that causes this feeling some people like, most people ignore and a handful of people hate so much that the time released tablets may in fact provide an adequate (yet obviously more expensive) alternative to powders or caps to max out their carnosine stores while avoiding the inconvenient sensation of "pins and needles" punctuation their flesh.

Image 2: Time released beta alanine in its natural form

Dr. Andro's tip for outsmarting the supplement industry: The wise guy (or girl) you are you probably don't really need me to tell you that by just sprinkling your beta alanine over your food or sipping on it in the course of your workout (or your daily routine) you can make your own "time-released beta alanine formula". A formula, of which you could even say that it was "invented by nature itself"... after all, poultry is the richest source of dietary beta alanine, so if you are into the whole ancestral diet concept spicing up your chicken drumsticks with another 1g of bet alanine would be the "paleo way of time-released beta alanine supplementation" *rofl*

A pros pos maxing out carnosine stores. I suggest you come back tomorrow if you are interested in whether or not doing this is actually worth it. "Unclear", "possibly", "negligible", "likely beneficial", "likely harmful" and the rest of the vocabulary that is used in a recent study from the Department of Exercise and Sport Science at the University of North Carolina to evaluate the effects the scientists observed on acute exercise performance after 28 days of beta alanine supplementation does in any case not sound that enthusiastic.

Update: Click here for the second part of this beta alanine double-whammy.

Chronic High Dose BCAA Supplementation Reduces Endurance Performance by 43% Plus: How Ammonia, Glutamine, Arginine & Low Carb Could be Involved

Tired, exhausted, had to cut your workout short today? Is it the flu, or just too much BCAAs?

When some is good and more is better, even more is not necessarily going to be 'betterer' - and that's not simply due to the fact that there is no comparative to an adjective that's already in the comparative. Therefore it is actually not surprising that a team of researchers from the Department of Food and Experimental Nutrition at the Faculty of Pharmaceutical Sciences, the Department of Nutrition at the School of Public Health and the Department of Physiology and Biophysics at the Institute of Biomedical Sciences of the University of Sã o Paulo in Brazil has just published the results of a study (Falavigna. 2012) which demonstrates that there is an upper limit to the benefits of BCAA supplementation. What I guess will be surprising at least for some not so regular SuppVersity visitors, is that there is more than just a saturation effect: Too much BCAAs can actually have ergolytic (= anti-ergogenic) effects - at least under certain circumstances.

Another chapter in the book of good things that turn against you, when taken in excess

In their latest paper that has just been published in nutrients, Gina Falavigna and her colleagues analyzed effects of chronic BCAA supplementation on exercise performance in male Wistar rats. Based on previous animal and human data and the still widely supported, though actually experimentally non-validated (cf. Meeusen. 2007) theory that BCAAs would work their non-hypertrophy specific, endurance enhancing magic via the blockade of exercise induced 5-HT (serotonin) accumulation in the brain, the researchers speculated that ...

"[...] chronic BCAA supplementation (through the diet, using different BCAA  concentrations) would increase performance in rats subjected to a swimming exhaustion  test." (Falavigna. 2012)

To verify this hypothesis, Flavigna et al. randomized their rats to three different groups receiving either the standard AIN-93M diet for the maintenance of adult rodents (control group) or the same diet with additional additional 3.57% (group S1) and 4.76% (group S2) BCAAs at a ~2:1:1 ratio of lecine : valine : isoleucine (the BCAAs were manufactured by the Brazilian branch of Ajinomoto). The rodents in the S1 and S2 groups did thus receive 50% and 100% more branched-chain amino acids than the rodents in the control group which had to contend themselves with the BCAAs in the casein fraction of their diets (see figure 1, right). In order to assure that the diets would be isocaloric, an amount of starch equivalent to the amoung of BCCAs that had been added to the chow was removed from the supplemented diets.

Overall, the study lasted for six weeks. During this time the rodents were subjected to a 1h/day weight bearing swimming protocol five times a week. In the first two weeks, the rats were ...

"[...] adapted to the water medium and exercised with increasing overloads attached to the tail until an overload corresponding to 5% of total body weight was reached. This final overload was used until the end of the training protocol [...] The overloads were corrected weekly according to the variations in animal weight.  The efficiency of the training protocol was assessed on the basis of maximum activity of the enzyme citrate synthase in the soleus muscle, with a group of sedentary animals being used as the control for this parameter." (Falavigna. 2012)

Neither the overall amount of food nor the body weight gain of the rodents in the control, and the two exercise groups showed any statistically significant difference. The latter cannot be said about the exercise performance, as well as the accumulation of ammonia, though (see figure 1):

Figure 1: Exercise duration and plasma ammonia levels during / after swmming test (left) and macronutrient composition of the experimental diets (right; based on Falavigna.. 2012)

While the rodents in the +50% BCAA group (S1) do show the expected increase in endurance (+37%) their peers in the high dose (+100%) BCAA group (S2) experienced an even more pronounced drop in endurance performance (-43% vs. control), which went hand in hand with a profound increase in blood ammonia (+34%).

"Ammonia is a ubiquitous metabolic product producing multiple effects on physiological and biochemical systems. Its concentration in several body compartments is elevated during exercise, predominantly by the increased activity of the purine nucleotide cycle in skeletal muscle. Depending on the intensity and duration of exercise, muscle ammonia may be elevated to the extent that it leaks (diffuses) from muscle to blood, and thereby can be carried to other organs. The direction of movement of ammonia or the ammonium ion is dependent on concentration and pH gradients between tissues. As such, ammonia can also cross the blood-brain barrier, although the rate of diffusion of ammonia from blood to brain during exercise is unknown. It seems reasonable to assume that exhaustive exercise may induce a state of acute ammonia toxicity which, although transient and reversible relative to disease states, may be severe enough in critical regions of the central nervous system (CNS) to affect continuing coordinated activity. Regional differences in brain ammonia content, detoxification capacity, and specific sensitivity may account for the variability of precipitating factors and latency of response in CNS-mediated dysfunction arising from an exercise" stimulus, e.g., motor incoordination, ataxia and stupor. There have been numerous suggestions that elevated ammonia is associated with, or perhaps is responsible for, exercise fatigue, although evidence for this relies extensively on temporal relationships." (Falvigna. 2012; my emphasis)

Mark the last words of the previously cited paragraph: "[E]vidence for [the role of ammonia] in exercise fatigue relies extensively on temporal relationships". It is thus - as for now - a solely corollary, not yet a causative association, of which I do however feel that it would be very likely to turn into a causal one if someone actually measured the influx of ammonia into the brain during a workout.

Wait, ammonia? But ain't it more likely that the BCAAs block the uptake of tryptophan?

What's for sure is that another hypothesis, which relates to the blockade of tryptophan uptake can be ruled out as an underlying reason of the differences. After all the scientists who argue that ...

"[t]he increased synthesis of serotonin during exercise may be related to the development of central fatigue, because this neurotransmitter has several physiological functions, since it operates by  mood, lethargy, individual behavior, regulation of sleep, body temperature and blood  pressure, appetite suppression and changes in perceived exertion." (Falavigna. 2012)

...actually measured the 5-HT levels and observed no differences between the dietary groups. Overall, the study results to thus clearly indicate that both, medium nor high dose "chronic BCAA supplementation was not effective in improving the main parameters indicative of central fatigue" (Falavigna. 2012) - well, at least as long as we still stick to the hypothesis that the latter is induced by the accumulation of 5-HT in the brain.

Forget about tryptophan and serotonin, focus on ammonia

The fact that neither the high, nor medium dose of BCAAs did exert any effects on the serotonin levels in the brain does yet not explain why the medium dose supplementation regimen produced ergogenic, while the high dose regimen induced ergolytic effects.

The occurrence of direct toxic effects due to (too) high amounts of branched-chain amino acids can be ruled out based on previous studies in which the administration of more than 10g/kg body weight of BCAAs (the human equivalent would be 130g+ per day), as well as dosages of 2.5g/kg body weight chronically did not entail any toxic side effects (Shimomura.  2004). The same is true for other confounding variables, such as the citrate synthase activity, a measure of the general efficiency of the training protocol, bood glucose, insulin,free fatty acids, and lactate levels, as well as liver and muscle glycogen content, which were virtually identical in both groups. This leaves us with the increase in plasma ammonia as our 'last resort' to explain the -58% shorter swimming time in the high (S2) vs. medium (S1) dose BCAA group (-43% lower vs. non-supplemented control).

Figure 2: The reduced performance of the high BCAA group could well be related to peripheral and/or central ammonia build-up as a results of increased BCAA oxidation, camparably low glutamine intakes and the rate-limited enzymantic conversion and recycling of gluatmine (illustration originally from Earrante. 2003). Studies by Snow (2000) and Carvalho-Peixoto (2007) suggest: Both carbohydrate & glutamine supplements could help.

Based on what we know about the mammalian body, the increased build-up of ammonia in the high BCAA group could be a result of the unfortunate combination of temporary energy shortage and learned wastefulness' in a situation, where the otherwise sparse BCAAs are available in abundance. Furthermore, with a glutamine content of only 9-13% in the casein fraction of their diets (Swails. 1992), the rodents in the high BCAA group did ingest more than 2.6-3.8 times more BCAAs than glutamine; a fact which may have contributed to a temporary glutamine deficiency as a result of its increased use in the detoxification of the ammonia that's generated when the BCAAs are oxidized. The resulting peripheral and possibly central ammonia build-up (see figure 2) could then have begun to intoxicate liver and brains of the rodents and thus hampered gluconeogensis (normal levels stimulate, high levels of ammonia hamper gluconeogensis; cf. Fritz. 1988) and induced central fatigue (Wagenmakers. 1990; Nybo. 2004) -- and that not despite, but rather due to the chronic "high dose" BCAA supplementation (HED ~50g/day).

So do I have to drop my BCAAs now or what? Whether these results are relevant for you will probably depend on a whole host of parameters, which include

• the type, intensity and duration of exercise you do, 
• the ratio of BCAAs to glutamine in your diet,
• the amount of arginine, which acts as a substrate for the urea cycle and is therefore necessary to for the excretion of ammonia by the kindeys (Schaefer. 2002),
• the amount of carbohydrates in your diet (with more = less amino acid oxidation = lower ammonia and very low carb = you are in trouble; e.g. Czarnowski. 1995; Snow. 2000; Carvalho-Peixoto. 2007), 

... and those factors I will probably have forgotten to mention now. Unless you don't forget that you can neither lifve from BCCAs and protein alone, but accept the neflglected truth that too much protein is about as bad a too little protein, you can file this post under "show your stupid friends" and get back out, when they complain about feeling sick, bloated and fat "despite" eating a BCAA supplemented high protein, low carb (and often even low fat) diets.

References:

• Carvalho-Peixoto J, Alves RC, Cameron LC. Glutamine and carbohydrate supplements reduce ammonemia increase during endurance field exercise. Appl Physiol Nutr Metab. 2007 Dec;32(6):1186-90.
• Errante LD, Petroff OA. Acute effects of gabapentin and pregabalin on rat forebrain cellular GABA, glutamate, and glutamine concentrations. Seizure. 2003 Jul;12(5):300-6.
• Falavigna G, de Araú jo Junior JA, Rogero MM, de Oliveira Pires IS, rio Graç a Pedrosa R, Martins Junior E, Alves de Castro I, Tirapegui J. Effects of Diets Supplemented with Branched-Chain Amino Acids on the Performance and Fatigue Mechanisms of Rats Submitted to Prolonged Physical Exercise. Nutrients 2012. 4; 1767-1780.
• Fritz S, Bohnensack R. Stimulation of alanine metabolism in rat liver by ammonia. Biomed Biochim Acta. 1988;47(12):923-32.
• Meeusen R, Watson P. Amino acids and the brain: do they play a role in "central fatigue"? Int J Sport Nutr Exerc Metab. 2007 Aug;17 Suppl:S37-46.
• Nybo L, Dalsgaard MK, Steensberg A, Møller K, Secher NH. Cerebral ammonia uptake and accumulation during prolonged exercise in humans. J Physiol. 2005 Feb 15;563(Pt 1):285-90. Epub 2004 Dec 20. 
• Schaefer A, Piquard F, Geny B, Doutreleau S, Lampert E, Mettauer B, Lonsdorfer J. L-arginine reduces exercise-induced increase in plasma lactate and ammonia. Int J Sports Med. 2002 Aug;23(6):403-7.
• Shimomura, Y.; Murakami, T.; Nakai, N.; Nagasaki, M.; Harris, R.A. Exercise promotes BCAA catabolism:  Effects  of BCAA supplementation on skeletal muscle during exercise.  J. Nutr.  2004, 134, 1583S–1587S.
• Snow RJ, Carey MF, Stathis CG, Febbraio MA, Hargreaves M. Effect of carbohydrate ingestion on ammonia metabolism during exercise in humans. J Appl Physiol. 2000 May;88(5):1576-80.
• Swails WS, Bell SJ, Borlase BC, Forse RA, Blackburn GL. Glutamine content of whole proteins: implications for enteral formulas. Nutr Clin Pract. 1992 Apr;7(2):77-80.
• Wagenmakers AJ, Coakley JH, Edwards RH. Metabolism of branched-chain amino acids and ammonia during exercise: clues from McArdle's disease. Int J Sports Med. 1990 May;11 Suppl 2:S101-13.

Leucine Only Tops Ergogenic Effects of BCAAs: Increased Alanine Cycle Activity Spares Muscle Glycogen, Boosts Endurance Performance - BCAAs Have Opposite Effect

Alanine is the liver's favorite gluconeogenic amino acid and leucine appears to increase its usage.

Being among the first to learn about the "Glucose-Repartitioning Effect of Iso-Leucine" in February 2013 (read up on it), you, as SuppVersity reader, belong to the selected few who know that valine and isoleucine may be more than unnecessary props in the leucine-powered BCAA show. With the recent publication of a rodent study from the University of Sao Paulo in Brazil (Campos-Ferraz. 2013), however, it looks as if you had to revise your perspective on the purportedly auxiliary BCAAs - at least, with respect to their ability to reduce fatigue, and muscle and liver-glycogen degradation, in trained rats and possibly (!) humans.

So what did the Brazilian researchers do?

Basically, the idea Campos-Ferraz et al. had in mind, when they came up with their 8 week exercise + 2 week supplementation protocol (see Table 1) was to ...

Table 1: Exercise progression; suppl. was initiated in w7 after lactate test

"evaluate effects of the use of supplementation with leucine or a mixture of BCAAs in trained rats submitted to an exercise-induced protocol of glycogen depletion.

Furthermore, we attempted to investigate muscle and liver biochemical parameters that were not performed in the previous study in order to elucidate the role of BCAAs in glycogen depletion. " (Campos-Ferraz. 2013)

In other words: The researchers wanted to find out whether or not leucine would exert identical, less or more pronounced effects on muscle glycogen use and endurance performance in rodents that the full spectrum of branch-chained amino acids, i.e. leucine, valine and isoleucine.

Contrary to what bro-science and the shiny ads of the supplement industry are suggesting, the scientists' fundamental hypothesis was that the BCAAs supplementation would impair the rodents endurance capacity, because the branched-chain amino acids would be used in muscle to yield acetyl-CoA. This, in turn could reduce the activity of the glucose-alanine cycle, by which the muscles are supplied with alanine-derived glucose from the liver and (once the BCAAs got burne) result in an earlier onset of fatigue.

BCAAs are "glycogen depleters"?!

If you take a look at the data Campos Ferraz et al. gathered in the testing sessions at the end of the supplementation period, in the course of which the rats received an oral gavage of 166mg/kg per day (in human terms this would be ca. 3-3.5g per day) of BCAAs or leucine, it is quite obvious that the  the leucine group had a significantly lower muscle and liver glycogen degradation ratios than the BCAA group.

Figure 1: Liver & mucle glycogen degradation and time to exhaustion (expressed relative to placebo); muscle TCA intermediate content and enzyme activity / concentration (Campos-Ferraz. 2013)

Compared to the placebo group, only the ratios were different.  While the placebo group had the lowest liver glycogen use and a high muscle glycogen use, the supplemental leucine induced a shifted from muscle to liver glycogen and did thus exert muscle specific glycogen sparing effects.

As the researchers point out, these observations stand in line with their original hypothesis: Leucine can spare a significant amount of muscle and liver glycogen and thus produce a highly significant increase in resistance to exhaustion compared to the mixture of BCAAs (P<0.001).

This is not the first study to cast a bad light on BCAA supplementation. As a SuppVersity veteran, you will remember my November 2012 article "Chronic High Dose BCAA Supplementation Reduces Endurance Performance by 43%" | read more, as well as the more recent investigation into the  "Neurotransmitter Depleting Effects of Branched Chain Amino Acids (BCAAs) and Their Potential Ergolytic, Anxiogenic & Depressive Downstream Effects" | read more.

If we compare the endurance performance of the leucine rodents to that of the placebo group, this does yet cast a slight shadow on the overall image of the glorious ergogenic, and, even more so, the purported performance enhancing effects of BCAAs. Despite measurable differences in the time to exhaustion, the actual endurance increase in response to the leucine supplement is relatively small.
 
If you take another look at the data in Figure 1 you will probably notice the significant increase in TCA cycle intermediates (citrate and malate) in the BCAA group. These changes provide further evidence that the provision of all three branch-chain amino acid emphasized the use of glucose as a main substrate to sustain the endurance activity.

"Mouse vs. man": Can we ignore the differences in BCAA metabolism?


At this point, it may however be about time to point out that the activity of the BCAA catabolizing enzyme branched-chain keto acids dehydrogenase complex (BCKD) in humans is quite different from that in rats.

"In the latter [the rat], liver BCKD is almost completely unphosphorylated (activated) in basal state, making it possible to metabolize more rapidly BCKA from the portal blood; in humans, BCKD in liver is normally phosphorylated (inactivated) in order to spare BCAAs for protein synthesis." (Campos-Ferraz. 2013)

In other words: While rodents use BCAAs mostly as an energy source, the human body spares them as a potential protein anabolic.

In view of the fact that the BCAAs are not used to the same degree as an alternative substrate in the human vs. the rodent liver, it is actually not very surprising that the results of the study at hand appear to conflict with data from a previous study by the same laboratory (Gualano. 2011). In the corresponding experiment, Gualano et al observed measurable increases in exercise capacity and lipid oxidation in human subjects during endurance exercise after muscle glycogen depletion in response to the provision of 300mg/kg BCAAs per day.

So, the study is totally irrelevant, right? Not really, no. The fact that we are not able to use BCAAs as a readily available energy source like rodents does after all not mean that they must necessarily have the opposite effects on us. In fact, you all know that the vast majority of studies investigating the beneficial effects of BCAAs on endurance performance in humans yielded a null-result (!) - despite the fact fact that generations of researchers have been convinced that the inhibition of tryptophan uptake must blunt the exercise induced onset of fatigue (learn more in the articles cited in the red box).

Don't forget the endurance reducing increase in glucose usage that appears to be caused by isoleucine (and maybe valine) can also be beneficial: "The Glucose Repartioning Effects of Isoleucine" | read more.

The actual new information this study brings to the table is thus not that BCAAs are not ergogenic. It's rather the previously overlooked leucine induced acceleration of the glucose alanine cycle in liver. It is the activation of this (catabolic!) powerhouse by the means of which leucine "might have an interesting use in physical performance in prolonged or submaximal exercise, where muscle glycogen stores are more likely to be depleted" (Campos-Ferraz. 2013). It should be noted, though, that these effects are probably only observed after the glycogen levels are fully depleted - after an intense workout, towards the end of a race or after an fasted training - in those situations, the performance benefits may even be more more significant than in the study at hand.

Reference:

• Campos-Ferraz PL, Bozza T, Nicastro H, Lancha AH Jr. Distinct effects of leucine or a mixture of the branched-chain amino acids (leucine, isoleucine, and valine) supplementation on resistance to fatigue, and muscle and liver-glycogen degradation, in trained rats. Nutrition. 2013 Nov-Dec;29(11-12):1388-94.
• Gualano AB, Bozza T, Lopes De Campos P, Roschel H, Dos Santos Costa A, Luiz Marquezi M, et al. Branched-chain amino acids supplementation enhances exercise capacity and lipid oxidation during endurance exercise after muscle glycogen depletion. J Sports Med Phys Fitness 2011;51:82–8

Beta Alanine Fails to HIIT Back: No Increased Training Effect in Response to Nine 4x4 Min HIIT Workouts W/ BA Preload, But Evidence in Favor of Chronic Supplementation

Contemporary scientific evidence suggest that you have to pick the right type of (short intense) exercise if you don't want your beta alanine supplement to end up as another "false starter" in your closet.

In the past couple of weeks beta alanine (BA) has gotten some bad press, here at the SuppVersity. While some conspiracy theorists may already have smelled a personal vendetta of a sodium bicarbonate advocate like myself against its 'high tech competitor', the actual reason for the negative, or at least not necessarily exciting news is the exercise specificity of beta alanine (BA) supplementation.

The most recent BA study from the  University of Bern and the Swiss Federal Institute of Sport in Switzerland and the Karolinska University Hospital in Sweden is yet another rather disappointing BA study to support my previous assertion that the benefits for the average gymrat are largely overblown.

What did the researchers do

As Gross et al. point out, the aim of their two-part intervention study was to alter the physiological systems discussed above in ways that could improve severe exercise performance. In that, their hypotheses were that

1. 

   If we look at the results of previous studies, it appears that the question, whether BA ↪ promotes or ↪ blunts the ergogenic effects of baking soda does also depend on the type of exercise.

   ... HIIT, by improving VO2max and VO2 kinetics, would enhance aerobic energy contribution during severe cycling exercise
2. ... beta-alanine supplementation, by increasing intramuscular carnosine, would improve buffering capacity and reduce pH disturbance, or otherwise dampen muscle fatigue during severe cycling exercise; and 
3. ... prior supplementation with beta-alanine would allow for greater training load and better recovery during HIIT,which would enhance benefits of training on physiological determinants of severe exercise performance. 

As a seasoned SuppVersity veteran you know about the profound training effect of high intensity (if you don't educate yourself). You will also know / have expected that the 38-day preload in the course of which the participants consumed either

• * supplements were provided as 400-mg gel capsules and taken with the 3 main meals and before bed
  4 x 800mg/day "purified beta alanine"* (BA), or
• 4 x 800mg/day maltedextrin (PLA),

would increase the intramuscular carnitine stores of the participants in the BA group. What you don't know, however, is whether the eight endurance, team, or combat sport athletes in the active study arm would also display lower serum pH levels, experience less fatigue, and record greater improvements in VO2max than the remaining nine subjects in the placebo arm of the study.

Let's take a look at the results

I guess, it doesn't make sense to keep you on the tenderhooks any longer, so let's see what happened  during and after the obligatory nine 4 x 4 minute interval HIIT sessions on a cycle ergometer (10 min warm-up; heart rate 90-95% of max; 3min light cycling between intervals).

Simply taking your beta alanine supplements with food increases the absorption of BA more effectively than fancy "time-release" caps or tablets | read more

Chronic vs. cyclic BA supplementation: It is an interesting side-finding of he study at hand that 9 HIIT sessions and a 7-day rest-period can reduce the carnosine overload in the vastus lateralis and vastus internus (the teardrop muscle) by statistically significant 6.5% and 12.2%, respectively. This would mean that a chronic high intensity overload can very well induce significant reductions in carnosine levels within less than a month. A workout fanatic who wants to keep his muscles supersaturated with carnosine on all 365 days of the year should thus not follow my previous suggestion to do 6-weeks on, 4-weeks off cycles. In view of the results of the study at hand, I will yet leave it to you to decide whether you feel this is actually worth the effort / money.

The sessions were performed as follows: Sessions 1-3, 1 day rest, sessions 4-7, one day rest, sessions 8-9; and all participants had been following their habitual training and nutrition regimen during the 38-day "preload".

Figure 1: Changes in VO2max, peak power output, max. blood lactate, and power at second ventilatory threshold in from baseline (pre) to post-supplementation (before HIIT) and from baseline (pre) to the end of the study (after HIIT +7-days)

If you read the text in Figure 1, you will be aware that the changes the scientists observed in response to the exercise regimen look impressive, but lack statistical significance. In the end, the results are thus way less exciting than the relative performance increases in the 10 ± 5% range would suggest.

It is difficult to say if the overall effect size is the reason that there were no significant inter-group differences. Since there were not differences at all (not even borderline or non-significant ones), it is however unlikely that a longer study duration and correspondingly more pronounced increases in VO2Max, peak power and co, as well as the likewise identical post workout glycogen synthesis and muscle fiber cross-sectional area would have yielded a significant advantage on part of the BA supplemented trainees. The fact that the increases in skeletal muscle buffering capacity reached significance only in the placebo group, would even support the exact opposite hypothesis, i.e. more pronounced long-term adaptive effects without beta alanine supplementation.

The 2012 meta-analysis by Hobson et al. demonstrated two things (a) BA produces predictable performance increases only in the 60-120s range and (b) the overall effect size is much smaller than what most people are (mis-)lead to believe, when they read the advertisements... ah "write-ups" on the Internet.

What do we make of these results? In view of the overall rather disappointing results, I am not sure if you feel that the 1.3% increase in aerobic activity and -5% decrease in O2 deficit is convincing enough to subscribe to idea that beta alanine powered carnosine loading is a viable strategy to improve the adaptive response to long(er)-duration interval training (here "longer" is 4-min).

In my humble opinion this is not the case. Not necessarily because I feel that BA is a supplemental non-starter, but rather in view of its exercise- / duration-specificity, of which Hobson et al. wrote in their 2012 meta-analysis that it restricts the usefulness of beta alanine to sports where the overall duration of high intensity muscular contractions is longer than 60s, but shorter than 240s. This is a pretty narrow margin and even within this "performance zone" the mean effect size of 2.85% does not come remotely close to what you'd expect to see when you read the boastful promises in the "write-ups" of the supplement industry.

References:

• Hobson RM, Saunders B, Ball G, Harris RC, Sale C. Effects of β-alanine supplementation on exercise performance: a meta-analysis. Amino Acids. 2012 Jul;43(1):25-37.
• Gross M, Boesch C, Bolliger CS, Norman B, Gustafsson T, Hoppeler H, Vogt M. Effects of beta-alanine supplementation and interval training on physiological determinants of severe exercise performance. Eur J Appl Physiol. 2013 Nov 9. [Epub ahead of print]

Building a Bigger Engine: Resistance After Endurance Training Increases Mitochondrial Biogenesis & Protein Synthesis and Ramps Up Fat Metabolism

Image 1: There is nothing wrong with some "classic cardio" training, especially if you spike it up to build your mitochondrial engine

In a recent review of the literature, J.M. Wilson from the University of Tampa analyzed the results of 27 studies to determine whether and to which extend concomitant endurance training does / could have detrimental effects on the outcomes of resistance training (Wilson. 2011). And I suspect that it will not surprise you that Wilson found negative correlations "between frequency (-.26 to -.35) and duration (-.29 to -.75) of endurance training [and] hypertrophy, strength, and power." What is yet also noteworthy is a similarly significant (p<0.05) correlation with lower body fat levels and maximal heart rates on part on those strength athletes who did some sort of endurance exercises. Now, a more recent study which is soon going to be published in Journal of Applied Physiology sheds some more light on the complex interplay of endurance and resistance training and the potential benefits of combining both to build a "bigger mitochondrial engine" (Sahlin. 2011).

Interestingly, the Swedish scientists started out with a diametrically opposed hypothesis. Sahlin et al. expected that the signaling of mitochondrial biogenesis, of which it is common knowledge that it is promoted by "classic" low(er) intensity endurance exercise, would be impaired by resistance exercise. To validate their hypothesis, the scientists had a group of ten healthy subjects (7 males and 3 females; age, 26 ± 1.2 (mean ± SE) yr; height, 177 ± 2.9 cm; weight, 72 ± 3.5 kg) perform either 60min of endurance exercise (65% of VO2Max on a cycle ergometer) alone (E), or in combination (R+E) with a subsequent bout of 6 sets of leg presses at workloads corresponding to 70, 75, 80, 80, 75 and 70 % of the individual 1RM with 3 min rest between each set (cf. figure 1)

Figure 1: Graphical overview of the study outline (based on Sahlin. 2011).

Muscle biopsies were taken before and after the exercise protocol, to which the subjects had been randomly assigned and which was repeated 2 weeks (4 weeks in the female participants to avoid any influence of the menstrual cycle) later with subjects from the E group performing E + R and vice versa. The results, I'll say so much, were by no means what the researchers had expected.

Figure 2: Changes in lactate and muscle glycogen content in response to endurance (E) and combined endurance and resistance (E+R) training (calculated based on Sahlin. 2011).

While there were the expected differences in lactate levels, and glycogen content of the biopsied legs (cf. figure 2), the increase in the phosphorylation of mTOR and its upstream regulator Akt (you should know these promoters of protein synthesis from the posts in the Intermittent Thoughts series and my dissertations on other studies, by now ;-) was not only exclusive to the endurance + resistance training group (E+R), it was probably also much more pronounced than one might expect with 6 sets of leg presses and lead to an almost dramatic increase in p56Sk1 phosphorylation (do I have to mention that this happened "although" the subjects trained >12h fasted and remained fasted for the whole study period?) - a relatively reliable marker for protein synthesis (cf. figure 3).

Figure 3: Changes of key enzymes envolved in the phosphorylation of key enzymes in the protein synthetic cascade in response to endurance (E) and combined endurance and resistance (E+R) training (calculated based on Sahlin. 2011).

Morover, and totally contrary to what the scientists had expected, the expression of the key enzyme for mitochondrial biogenesis and increased fatty acid oxidation, PDK4 was significantly elevated, not suppressed, in response to the additional leg training (cf.  figure 4).

Figure 4: PDK4 phosphorylation (arbitrary units) in response to endurance (E) and combined endurance and resistance (E+R) training (calculated based on Sahlin. 2011).

The research hypothesis that a (relatively short, but intense) bout of resistance training subsequent to a mitogenic "classic" cardio regimen would blunt the beneficial effects of the latter on mitochondrial biogenesis is thusly more than falsified. As it turns out, the 6% increase in total work-load due to the addition of the 6 sets of leg presses makes a huge and desirable (!) difference (way beyond what an over-simplified workload = output equation would explain) in terms of "building a bigger engine" - an engine that will keep you lean on a bulk and help you lean out while your dieting.

If you are no powerlifter, it is thus probably no mistake to keep some "classic cardiovascular" exercise in your regimen, especially if you spice it up with a subsequent short bout resistance exercise - another option, and I am repeating myself here, would obviously be a high intensity cardio session (cf. HIIT). That being said, change has time and again proven to be the key to continuous improvements in exercise performance, muscular growth and strength, to incorporate both spiced up "classic cardio" and HIIT in your routine could not only improve your results (in view of the protein synthetic response, you could even "grow" on such an E+R day), it will also prevent you from getting bored with performing the same routine day in and day out and if you asked me, that is an even more fundamental key to success than a X% increase in the phosphorylation of whatever key enzyme ;-)

Intra-Workout Supplementation: Increased Carbohydrate Oxidation with L-Arginine, Lower Fat Oxidation with Glucose & Lowest Rate of Perceived Exertion with Plain Water

Image 1: This bird certainly knows about the importance of adequate hydration ;-)

Have you been at the gym today? If so, what kind of beverage have you been sipping in the rest-periods between your sets, your sprints or during your regenerative (not fat burning ;-) "classic" cardio exercise? Was it Funky XYZ the latest and greatest intra-workout product on the market? If so, you better check out its ingredients, who knows maybe the "latest and greatest" turns out to be quite counterproductive towards the goals you have been setting after reading one of the last two installments of the Intermittent Thoughts? Let's assume you are the "Peter Griffin"-type of chubby - in that case, I hope that your Funky XYZ did not contain glucose, maltodextrin, waxy maize, or any other of the sugars of which the supp companies are going to tell you that they "superior" to the white poison your granny uses in her delicious muffins. Why? Well, according to a soon to be published study by scientists from the Massey University in Wellington, New Zealand, as little as 12g of glucose will reduce the amount of endogenous fatty acid (i.e. the stuff your body is using to hide your abs ;-) oxidation by -22%! Sounds terrible, doesn't it? Well, let's look at some details to decide whether those -22% will really make a difference and what effects the presence of l-arginine and l-glutamine in your intra-workout supplement could have had.

150 min @ 177 Watt + Glucose + (Glutamine or L-Arginine) = ???

Figure 1: Composition of the intra-workout supplement; sodium citrate base + 12g glucose (glucose) and additional 1g l-glutamine (Glu + L-Glutamine) or 0.1g l-arginine (Glu + L-arginine)

It stands out of question that adequate hydration is of utmost importance, when it comes to maximizing athletic performance (incidentally, the same is true, when it comes to "burning fat"). What athletes should drink before (pre-hydration), during (hydration) and after your workouts (re-hydration) is thusly one of the classic topics of exercise science and the recent study by D.S. Rowlands et al. is thusly probably #1001 on the never-ending list of investigations into the optimal mineral and nutrient composition of intra-workout drinks. For us, it is of interest, because it is one of the few which investigated the differential effect of the amino acids l-arginine and l-glutamine on substrate utilization, plasma glucose, lactate and sodium levels and rates of perceived exhaustion in eight male cyclists and triathletes during 150min (!) of cycling at 50% of the individually predetermined peak power (this is noteworthy, because 50% of their peak power equalled 177 W, which is not exactly "light" exercise), in the course of which the athletes consume 150ml of a fluid containing a 0.95g sodium base and either 12g of glucose alone or a combination of glucose and either 1g of l-glutamine or 0.1g of l-arginine (cf. figure 1).

Figure 2: Oxygen consumption (L/min) and substrate utilization (g/min) in 8 trained cyclists / triathletes during 150 min of cycling at 177W with 150ml of four different intra-workout drinks (data adapted from Rowlands. 2011)

As a seasoned student of the SuppVersity, it should not surprise you that the exogenous (i.e. from the outside) supply of glucose produced a -22% shift in substrate oxidation from fatty acids to the now more readily available carbohydrates (cf. figure 2). What you have probably not expected, though, is that the addition of the minuscule amount of l-arginine (which is btw. about what you will get with many of the proprietary blends in the still incredibly popular "NO-boosters") would promote this shift by increasing the total amount of oxidized carbohydrates by another ~10% over the 12g glucose solution alone.

Figure 3: Comparison of total / relative substrate utilization for the 12g glucose + 0.1g arginine, the 12g glucose and the water + sodium citrate groups (data adapted from Rowlands. 2011)

Now you are stunned, hah? So after all it is yet not your fault that you cannot see your abs. It's your NO-suppement! Well, not exactly. I mean take a look at the way I arranged the data in figure 3. You will probably acknowledge that the 12g glucose + 0.1g l-arginine group "burned" more energy - if you want it in calories (remember this is stupid ;-) 0.68kcal/min or 102kcal during the whole session and then come back to the -22% reduced fatty acid oxidation and lament: "But Dr. Andro, they burned 22% less fat than the water-only group! Now I know why I don't get lean." If that is your train of thought, I would invite you to continue the idiotic kcal number crunching and calculate on how much fat the poor l-arginine group would have missed to burn... well, it's the "exorbitant" amount of 170mg/min or - for the whole session 25.5g! While this may be more than one tablespoon of coconut oil, I guess you will probably admit that this probably is not the reason your abs are still covered by a thick layer of flabby adipose tissue, won't you?

Arginine reduces oxygen cost at the expense of glucose

Now, the real interesting findings of the studies are thusly not the changes in substrate utilization but rather the profound impact the addition of the two amino acids had on the lactate levels during the 150min of cycling (cf. figure 4) and the rates of perceived exertion (RPE).

Figure 4: Plasma lactate levels (mmol/L) in 8 trained cyclists / triathletes during 150 min of cycling at 177W with 150ml of four different intra-workout drinks (data adapted from Rowlands. 2011)

The latter (RPE), and this is actually quite surprising, were minimal in the water + sodium citrate group and maximal in the 12g glucose + 1g l-glutamine group (0.8 pts greater on a 0-7 scale). The RPE values of the arginine group, on the other hand, were only marginally elevated and that despite the significant increase in glucose clearance, which, by the way, has also been observed by McConell et al. (McConell. 2006) and Linden et al. (Linden. 2010). 

In view of recent studies such as Greer et al. (Greer. 2011), who observed a small, but statistically significant decreases in endurance during a strength training circuit in response to Arginine-Alpha-Keto-Glutarate (AAKG) supplementation, it is yet very unlikely that the observed effects of an arginine-enriched glucose containing intra-workout supplement observed in this study "have the potential to benefit endurance exercise performance" (which is what the scientists, much to my surprise, conclude). Another thing is yet more than likely, I would even say it is 100% certain: Neither the results of this nor of any future study will change the sales ranks on Bodybuilding.com & Co., where the purported NO-Boosters (and factual stimulants) still are the front-runners of the "TOP 10 selling products" ;-)

Additional(!) HIIT Training Beneficial for Professional Judo Athletes: +15% Increases in Peak and Mean Power & Less Body Fat after 8-Week Training Camp.

Image 1: The Korean National Team - this are the kind of study subjects you want to look for if you are searching for studies that may help you, a fit physical culturist to improve your performance (img Yahoo)

Those of you who have been following the SuppVersity posts for quite some time now, know that I have continuously been ranting against classic endurance training. Not so much, because I think that this is not a sport you can enjoy (I know from personal experience that the "joy" can easily become addictive, though), but because many people perform what they think would be "healthy cardiovascular exercise" with the false expectation that running a marathon will improve their health and physique - more often, than not, the opposite is the case. And negative effects on both your physique (unless you consider being called a skeleton flattering) and longterm health become almost inevitable, when your daily 30 minutes of jogging or your 1h brief walk with your dog progressively increases to a frantic 10k run.

To each his own high intensity training

Image 2: Add 100-150lbs to a weight-west and test how "low" the intensity of a 4km/h walk on a treadmill is for the morbidly obese subjects in the studies that perpetuate the myth of the fat-burning effects "low intensity" exercise (img rosstraining.com).

And while the medical orthodoxy keeps putting out review after review emphasizing how beneficial classic endurance exercise is for the obese prediabetic, they do not give a damn that the 4km/h walk on a treadmill that makes the 250pound sedentary housewife sweat, pant and lose weight, will not have any impact on the girl with the unsexy love-handles who finally wants to get the body of the Shape cover models she is admiring. I mean, think about it: It's all about intensity! If the girl with the love-handles grabbed one of those military backpacks and loaded it with 5x30lbs plates, hopped on the treadmill and started walking at 4km/h, what would you call that? I would call it High Intensity Training (HIT). Now, the girl would probably fall off the treadmill every 30s because the load was way to heavy. What would you call it if she jumped back on after catching her breath? I would call it High Intensity Interval Training (HIIT). 

Assuming that you got the message, it should stand out of question that you as a reasonably fit physical culturist can adopt short (max. 50min) bouts of low intensity endurance training as a means of regeneration, but if you are looking to improve your physique or exercise performance (outside of long-distance running) you are way better of if you follow the example of the 29 judoists from the Yongin University in Korea who participated in an 8-week study at the Korea National Sport University in Seoul (Lee. 2011).

Figure 1: Subject characteristics (left) and training program (right) of the 29 judoist participating in study (Lee. 2011)

If you take a look at the subject characteristics in figure 1 (left), you may note that this is the kind of study you and I must rely on, when we are designing our training routines if we want to improve our cardiovascular fitness level and shed the last unaesthetic pounds of body fat - and, if the results from this study translate into your training practice, the addition of an early morning HIIT sprinting session on Monday, Tuesday, Thursday and Friday (exact protocol cf. figure 1, right) could provide exactly that: a drop in body-fat and an increase in anaerobic performance. This is particularly noteworthy, because the subjects performed the interval training as part of an already arduous 8-week training camp with concurrent strength and judo training (I wonder if any of the participants was afraid to lose muscle ;-)

Figure 2: Effects of standard and standard + additional HIIT training on VO2Max, peak and mean power (left), as well as body composition in 29 judoists during an 8-week training camp (Lee. 2011)

With their already low body fat percentage of ~13% and a caloric intake of 3.500kcal/day (remember none of the athletes wanted to lose weight), the slight (and statistically non-significant), yet nonetheless evident body-recompositioning effect is certainly not to be scoffed at, if you look at the profound performance increases in the anaerobic peak and mean power test (cf. figure 2).

That the VO2Max, i.e. the aerobic performance did not benefit above the normal protocol is yet an oddity of the study, (cf. "HIIT Even For Infarction Patients") of which the scientists assume that it could be related to the fact that the normal training protocol alone would have been enough to max out on the already high aerobic capacity of the athletes. Which, and thusly we have again come full circle, leads me back to my initial recommendation to fine-tune your training protocol to your needs, which (I would hope) are completely different from the ones of the average sedentary, obese, pre-diabetic resident of the Western hemisphere. And in case you want to learn more about how to do that, I suggest you come back tomorrow, for the next installment of the Intermittent Thoughts with tipps on programming success that will work regardless of whether you will or won't use an intermittent fasting protocol ;-)

The Dipeptide Advantage!? +43% Muscle Glycogen With Whey Hydrolysate Compared to Matched Amino Acid Mix

The bigger the choice, the harder it is to choose. If you had to pick just one, go for the concentrate, if you want to afford two, get an isolate or hydrolysate and a casein protein.

"Whey is still the way to go." I believe I wrote, or at least thought just that only a couple of days ago, when I wrote about the wheat gluten hydrolysate in the last installment of the SuppVersity Science Round Up Seconds (click here to read all previous installments). Unfortunately, there is not just one way... ah, pardon me, I do of course mean "whey", there are many! And in order to completely confuse their customers supplement companies will spike their concentrates, isolates and even hydrolysates with free form amino acids, or - which is even more confusing - advertise their BCAA and EAA products as being made from whey protein. I mean, who cares if the damn molecules are unbound and indistinguishable, anyway? But let's get to the point, a soon to be published study from Japan could yield at least some insights into demonstrable and purported benefits of one over the other.

Whey hydrolysate or simply its aminos, what gets pro-glycogen job done?

Based on results from previous experiments in the course of which the researchers had found that the acute provision carbohydrate + whey protein hydrolysate (WPH) had superior effects on muscle glycogen repletion compared to iso-nitrous amounts of BCAAs (Morifuji. 2010a) Kanda et al. speculated that chronic supplementation with whey protein hydrolysate (WPH) should elicit similarly beneficial effects and could help them clarify the underlying mechanism of this glycogen boosting effects of WPH. To this ends, the researchers put a group of mice on diets that differed only terms of the protein composition of the diet.

• 

  Table 1: Composition of the test diets

  The control group's exclusive protein source was the casein from the standard chow.
• The whey amino acid (WAA) group received a chow, where 50g of the casein protein was replaced by an iso-nitrogenous amount free amino acids that was matched to the amino acid composition of the whey hydrosolate.
• The whey hydrolysate group received 20% of the original casein from the standard chow in form of a whey hydrolysate from Meiji Co., Ltd.

In the course of the 4-week study period, body weight and food intake of the animals were measured on a weekly basis. The mRNA expression, protein levels, and phosphorylation of glycoregulatory enzymes were measured in the gastrocnemius muscle. All rodents performed a regular 30-min swimming exercise protocol  in a fancy adjustable-current water pool five times per week and had to 'survive' a weekly (endurance-)performance test in the course of which they had to swim to absolute failure (defined as being drowning for 7s, already).

Figure 1: Food intake, liver weight, and visceral fat (left), as well as time to total fatigue during swimming exercise (right) of the rodents on control, WAA and WPH diets  (data adapted from Kanda. 2012)

Contrary to the data from this test, the body composition markers in figure 1 do not show any significant inter-group differences (positive or negative) the same goes for the food intake and the liver weight, as well as for the total body weight of the mice, which was totally identical (not shown in figure 1). The said swimming performance of the WAA and WPH group, on the other hand, were 32% and 48% higher than in the control group.

More glycogen synthetase = more glycogen content = more endurance

Now, despite the fact that this increase did - for whatever reason - not reach statistical significance, Kanda et al. are convinced that this increase in endurance must be a direct consequence of the increase in glycogen storage, which has been observed by Evans and Hughes in 1985 (Evans. 1985), already, and has been confirmed numerous times thereafter.

Figure 2: Glycogen content and glycogen synthetase levels (GS), as well as mRNA expression of glycogen synthase I and the ratio of phosphorylated to unphosphorylated GS (data based on Kanda. 2012)

And, as you can see, the actual data in figure 2 clearly confirms this hypothesis. The mice who had received whey protein hydrolysate (WPH) in their diets for the whole 4-week study period had significantly (p < 0.05) higher muscle glycogen levels than their peers in the control group (73%) and still more than 40% more total glycogen than the mice who had been fed the amino acid enriched chow (WAA). Quite impressive, right? And all that is just a consequence of a peptide induced elevation in glycogen synthetase and it's activity, which is indicated by the lower ratio of phosphorylated (=incative) to un-phosphorylated (=active) levels of this tightly regulated enzyme.

There is more to whey than BCAAs

The total amount or activity of the glucose transporter (GLUT-4) as well as the hexokinase activity (which figures in the phosphorylation of sugars) were not different between treatments and though the dreaded gluconeogenesis in the liver was not measured it is, given the high amount of carbohydrates in the diets of the rodents, very unlikely that the higher susceptibility of "fast" protein sources to be oxidized, when no other nutrients are available, played a significant role in the 'pro-glycogenic' of whey hydrolysate (after all the rodents consumed the protein as part of their chow), so that the most likely explanation for the superiority of the whey protein hydrolysate over the iso-nitrous amino acid mixtures remains their peptide content. In this regards, the authors of the study remark:

"The amino acid compositions of the two diets used in this study contained equal amounts of BCAA and leucine; however, muscle glycogen accumulation varied between diets. This result strongly suggests that not only the BCAA content but also the molecular form of BCAA found in the protein source might be important for muscle glycogen storage." (Kanda. 2012)

Kanda et al. do then refer to a previous study, in which his group had been able to demonstrate that BCAA-containing peptides in WPH, which have been shown to be markedly elevated (meaning they are not digested) after the consumption of whey protein hydrolysates (Morifuji. 2010) in a follow up study on human beings, do actually have the ability to stimulate the rate of glucose uptake in vitro (Morifuji. 2009).

Figure 3: Insulin response after the ingestion of 12.5g of either soy or whey protein or their respective hydrolysates (Morifuji. 2010)

"And what about insulin?"

I know that this question is now on your minds and in way you are right the only slight caveat you have to keep in mind before you blindly follow the scientists' outspoken advice to consume "carbohydrates mixed with WPH[to] enhance sport performance by increasing glycogen storage" (Kanda. 2012) would in fact be be the increased insulin response. Of the latter, the scientists found in the aforementioned 2010 human trial (Morifuji. 2010) that it is ~70% more pronounced in the first hour after the the ingestion of 12.5mg of whey protein hydrolysate and, once more compared to regular whey protein, still ~17% higher over the whole 2h period (the different proteins you see in figure 3 were all ingested on an empty stomach after an overnight fast by the 10 normal-weight subjets; the data I mentioned refers to the AUC values on the bottom of figure 3).

The insulin 'spike' is not necessarily a problem. At the right time in the right person it can even be highly beneficial.

Nevertheless, the results of the study at hand to actually confirm that before you invest in all sorts of useless pills, it may make more sense to make sure that you a) have more than just a single protein powder in your supplement arsenal and that you b) have been reading enough SuppVersity articles to be able to use them properly ;-) ... What? You still don't know how? Well assuming you have no problems with high insulin levels and are mainly interested in building muscle, you could start out with 20-30g whey + 15-25g casein (depending on your body size and needs) after a workout (see "Whey & Casein Work Hand in Hand for Muscle Protein Anabolism") and a 40g casein shake pre-bed (see "3.2kg of Lean Mass Overnight").

By the whey *lol*, I suppose you will see similar benefits from a whey isolate, although this would have to be tested. What does not need any tests, on the other hand is that you better make sure you don't forget the carbs! I mean, what is your body supposed to use as a substrate for the increased glycogen synthetase activity, if you are depriving yourself of carbohydrates? The protein your liver converts to blood glucose? Yeah, what a glorious idea... whatare your brain and your other organs going to use then? Ketones? No way, if you are pounding tons of fast acting glucogenic amino acids in form of protein shakes.


References

• Evans, W. J.; Hughes, V. A. Dietary carbohydrates and endurance exercise. Am. J. Clin. Nutr.1985, 41 (5, Supplement), 1146−1154.
• Kanda A, Morifuji M, Fukasawa T, Koga J, Kanegae M, Kawanaka K, Higuchi M. Dietary Whey Protein Hydrolysates Increase Skeletal Muscle Glycogen Levels via Activation of Glycogen Synthase in Mice. J Agric Food Chem. 2012 Oct 31.
• Morifuji, M.; Koga, J.; Kawanaka, K.; Higuchi, M. Branched-chain amino acid-containing dipeptides, identified from whey protein hydrolysates, stimulate glucose uptake rate in L6 myotubes and isolated skeletal muscles. J. Nutr. Sci. Vitaminol. 2009, 55(1), 81−86.
• Morifuji, M.; Kanda, A.; Koga, J.; Kawanaka, K.; Higuchi, M. Post-exercise carbohydrate plus whey protein hydrolysates supple-mentation increases skeletal muscle glycogen level in rats.Amino Acids 2010a, 38(4), 1109−1115.
• Morifuji, M.; Ishizaka, M.; Baba, S.; Fukuda, K.; Matsumoto, H.; Koga, J.; Kanegae, M.; Higuchi, M. Comparison of different sources and degrees of hydrolysis of dietary protein: Effect on plasma amino acids, dipeptides, and insulin responses in human subjects. J. Agric. Food Chem. 2010b, 58(15), 8788−8797.