Alanyl-Glutamine or Alanine + Glutamine? Dipeptide or Free Form Aminos? What Offer Maximal Muscle Protection?

"Wouldn't have happened if she'd used alanyl-glutamine instead of regular that cheap alanine + glutamine combo!" - True or False? Recent study says: False!

If you combine your liver's favorite gluconeogenic amino acids, i.e. alanine and glutamine, into a single peptide the result is called alanyl-glutamine and marketed as the ueber-potent alternative to regular l-glutamine supplements. It goes without saying that a comparison like this is about as stupid as comparing french fries with mayo to regular french fries and saying that the former are worse because they contain more fat, or whatever. Even if we didn't care about the physiological significance of the effects of alanyl-glutamine, we would obviously have to compare the purported cryogenic effects of this "innovative" dipeptide to those of a simple combination of free form amino acids to deserve the bragging rights for having created an advanced form of glutamine.

Alanine + glutamine vs. alanyl-glutamine - fight!

By now you are probably asking yourselves why I am bothering you with things like this. Right? Well, the reason is that Éder Ricardo Petry and his colleagues from the University of Sao Paulo must recently have been pondering the same question. To answer it, they conducted an experiment that would allow them to verify if the oral supplementation with l-glutamine and l-alanine as dipeptide has more pronounced muscle protective effects than a simple mixture of l-glutamine and l-alanine (GLN+ALA, both in their free forms) in a group of Wistar rats that are subjected to intense aerobic training (treadmill).

I know what you are thinking now: "Not another rodent study...", but think about it: How many people are willing to pay $50 and more on supplements without any in vivo evidence of their efficacy let alone long-term safety? Against that background Petry's rodent is a major advancement - isn't it?

True or False: You can (ab-)use glutamine to replenish your glycogen stores!? True! It sounds strange, but according to a study from the late 20th century glutamine is a pretty effective glycogen replenisher, even in the absence of your bodies favorite nitrous glucose precursor alanine | learn more

Don't get me wrong, there are a few alanyl-glutamine studies in humans, but there is not a single one that would compare the dipeptide to a reasonable placebo in an exercise scenario. I mean, who tells me that the basketball players in the 2012 study by Hoffman et al. wouldn't have experience the same beneficial effects on basketball skill performance and visual reaction time if their rehydration solution had contained alanine and glutamine or even glutamine alone? Yes, I know... the increased absorption: Well, let's just look at a fair comparison, i.e. the study at hand, and see what happens when the dreams of supplement formulators and reality meet ;-)

Ok, back to the facts - the exercise & supplementation protocol

The male Wistar rats, the researchers used in their experiment were exercised 5x per week - at increasing intensities: Starting with 30 and 45 min of treadmill running (incline 3°) at 20 and 22.5 m/min in the first three weeks, the speed and duration of their treadmill runs increased to 60 min at a speed of 25 m/min in week four and remained like that for the rest of the 8-week study period.

The supplements were administered via oral gavage in the course of the last 3 weeks, only. The daily doses for the animals in the dipeptide (DIP) and free form amino acid groups (GLN+ALA) were...

• 1.5g/kg alanyl-glutamine in the DIP group,
• 0.67g/kg l-alanine + 1.0g/kg l-glutamine in the GLN+ALA group, and
• plain water in the control group

The amount of of alanyl-glutamine the scientists used was calculated in such a way that the total amount of l-glutamine was the same as that of l-glutamine administered in its free form.

Changes? YES! Dipeptide benefits? Not really...

The gavage was provided 1 h after the end of each session of exercise, after which the animals had with free access to water and chow. To make sure that the results of the examinations on the last day of exercise would not reflect the acute effects of a single dose of the supplements, the animals were killed 10 h after the last exercise session.

Figure 1: Plasma glutamine, glutamate, ammonium, malondialdehyde, myoglobin, and creatine kinase activity in Wistar rats supplemented with alanyl-glutamine (DIP) or regular glutamine + alanine; data expressed rel. to control (Petry. 2013)

The virtually identical increases in l-glutamine and l-glutamate, you see in Figure 1 should thus represent the baseline and not the 'immediately post supplementation level' of these amino acids. For the exercise-induced accumulation of ammonium, malondialdehyde (MDA; indicates lower lipid oxidation), myoglobin and creatine kinase (both indicate lower muscle damage) the timing is not that important, anyway. What is important, however, is the fact that there were no physiologically relevant advantages for the "super glutamine".

DHEA & estrogen are alternative muscle protectors. Despite the fact that estrogen has repeatedly been shown to have muscle protective-effects, I would not suggest you steel your granny's HRT medication. DHEA on the other hand, may be something to consider - specifically if you are about to overreach, like the male subjects in a 2012 study by Liao et al. (learn more)

If we take a closer look at the p-values and the statistical significance of these changes, it turns out that, the minor increase in glutamate aside, all of the difference to the placebo group were statistically significant. The DIP vs. GLN+ALA differences, on the other hand, were marginal and reached statistical significance only in the case of the marker of myoglobin. Where the dipeptide has a physiologically probably irrelevant edge of 9% over the GLN + ALA combination.

Figure 2: Glutathione (GSH) and glutathione disulfide (GSSG = used glutathione) levels in soleus and gastrocnemius skeletal muscles of the rodents; data expressed relaitve to control (Petry. 2013)

For the muscular GSH levels, it does not look much different. In this case, there is however not even a statistical difference between alanyl-glutamine and the simple l-alanine + l-glutamine mix - neither for the universal anti-oxidant glutathione (GSH), nor for its "used form" glutathione disulfide (GSSG).

Does that mean that alanyl-glutamine is another supplemental rip-off?I would say that it's too early to use such harsh words. There was after all one statistically, and maybe even physiologically relevant difference between the two groups I didn't mention, yet: The dipeptide group presented with a different heat-shock protein response: They had higher HSP-70 and lower HSF-1 levels in the soleus and lower HSP-70 and lower HSF-1 levels in the gastrocnemius.

"Will training your biceps, heal your heart & protect your brain!?" - a study on the effects of exercise induced HSP increases suggests so | more

In view of the fact that the subsequent "deficit in HSP70 expression" is supposed to "impair recovery from these injuries" Petry et al. are probably right to point out that

"one cannot discard the possibility that part of the beneficial effects of high-intensity exercise training may be due to the enhancement of HSP70 expression which is exacerbated by glutamine supplementation."

In view of the fact that the total amount of proteins from the HSP70 and HSF1 family was increased in both groups, and the differences appear random, it is impossible to tell, whether the slight differences in HSP expression actually matter and whether this is an advantage for alanyl-glutamine or rather for the cheap free form amino acids.

Before future studies provide additional data based on which we can decide whether these differences are relevant and why they differ between slow- (soleus) and fast-twitch (gastrocnemius) skeletal muscle fibers, I'd say that the study at hand would suggest that alanine and glutamine have muscle protective effects irrespective of whether they are bound or not, when you ingest them.

References:

• Cruzat VF, Rogero MM, Tirapegui J. Effects of supplementation with free glutamine and the dipeptide alanyl-glutamine on parameters of muscle damage and inflammation in rats submitted to prolonged exercise. Cell Biochem Funct. 2010 Jan;28(1):24-30. 
• Cruzat VF, Tirapegui J. Effects of oral supplementation with glutamine and alanyl-glutamine on glutamine, glutamate, and glutathione status in trained rats and subjected to long-duration exercise. Nutrition. 2009 Apr;25(4):428-35.
• Hoffman JR, Williams DR, Emerson NS, Hoffman MW, Wells AJ, McVeigh DM, McCormack WP, Mangine GT, Gonzalez AM, Fragala MS. L-alanyl-L-glutamine ingestion maintains performance during a competitive basketball game. J Int Soc Sports Nutr. 2012 Mar 7;9(1):4.
• Petry ER, Cruzat VF, Heck TG, et al. Alanyl-glutamine and glutamine plus alanine supplements improve skeletal redox status in trained rats: Involvement of heat shock protein pathways. Life Sciences. 20 November 2013 [ahead of print]
• Rogero MM, Tirapegui J, Pedrosa RG, Castro IA, Pires IS. Effect of alanyl-glutamine supplementation on plasma and tissue glutamine concentrations in rats submitted to exhaustive exercise. Nutrition. 2006 May;22(5):564-71.

Speed Up Your Regeneration and Propel Your Gains by Taking a HOT Bath Bath 2-Days Before Arduous Workouts

Image 1: Are women tougher than men, because bathe more often? If you define toughness by your muscles resistance to eccentric exercise damage, the answer could be "YES!"

If you listened to Brooks, Carl and me on Super Human Radio, yesterday (download the podcast), you may remember me stating that 48h appears to be a good rule of thumb, as far as the rest periods between workouts for individual body parts are concerned (this assumes that you are young, healthy, reasonably conditioned and lift heavy). A recently published paper by Chad D. Touchberry  does now suggest that there may be another 48h window before your workout (Touchberry. 2012). One you would use a priori to improve your recovery a posteriori - preconditioning in a hot bath for 20 min at 41°C, 48h before a hard workout or competition!

Eccentric treadmill running = maximum muscle damage

At least in a rodent model, those 20 min of heat exposure in 41°C warm water lead to statistically highly significant decreases in exercise induced muscle damage, improved and accelerated the recovery process and, contrary to what could be assumed based on previous research on the expression of heat proteins (Frier. 2007), did not hamper, but promote muscle gains in response to an exercise protocol consisting that consisted of running at 18m/min down a -16% grade for 5 min. This protocol has been used as a model for injurious exercise repeatedly in the past and constitutes one of the standard tests in rodent, but also in human studies (e.g. Pumpa. 2011).

Figure 1: Creatine kinase (CK) activity and immune cell infiltration after eccentric exercise with (EE+HS) and without (EE) preconditioning via hot bath 48h before (data calculated based on Touchberry. 2012)

As the data in figure 1 goes to show, the hot bath (EE+HS) had significant ameliorative effects on both the muscle damage (indicated by CK and the black sections in the H&E-stained soleus muscle cross-sections in figure 1, right), of which the researchers state that, despite the fact that "the mechanism by which heat shock protects skeletal muscle from damage is currently unknown", the protection of skeletal muscle against damage in mice overexpresssing HSP70 (McArdle. 2004a) as well as the differential HSP72 elevation in the HS group 2h and 48 h following exercise collectively

[...] suggest that HSP72 or another heat sensitive protein (i.e.,alphaB-crystallin) may play a role in mediating cytoprotection of skeletal muscle cells.

Moreover, Touchberry et al. explain the existing discrepancies between their own results and previous results by Mc.Ardle et al. (Mc. Ardle. 2004b), who did not find reduced muscle damage after pre-treatment with hsp-inducing concentric exercise 10h prior to the (in my humble opinion questionable) in-vitro application of eccentric strain to skeletal muscle tissue, with the "greater time for HSP accumulation prior to the exercise stressor" in their (48h) vs. the Mc.Ardle study (10h), which is obviously yet another indicator that rest is one of the most under-appreciated determiners of workout efficiency (cf. my words on SHR ;-)

Regeneration is one thing, but are muscle gains another?

Now, I am well aware that one of the main reasons regeneration isn't sexy, is that it does not trigger the phosphorylation of Akt, m-TOR and all the rest of the sciency terms with which laymen are bombarded by the supplement industry these days.

Figure 2: Total protein, new myosin heavy chain (MHCNEO) content and p-Akt expression in soleus muscle 2h and 48h after the eccentric exercise bout (data calculated based on Touchberry. 2012)

The study at hand does even show that heat pre-treatment will actually reduce, not promote the phosphorylation of AKT 48h after the exercise bout (cf. figure 2). If you do yet take into account that the total protein concentration and MHCneo (novel myosin-heavy-chain motor proteins) content in the soleus muscle of the rodents was increased profoundly, I guess you will have to agree that it is unlikely that less damage, a faster regeneration, and as a consequence less need for protein to be recruited via p-AKT only to repair the damage is going to propel, not diminish your gains!

Practical implications & open questions

Once again, the obvious message of this study is: Not he who trains the most, but he who regenerates and rebuilds the best, gains the most! And adequate rest aside, preconditioning in a hot (not a "cold thermogenic" bath ;-) can help dampen the exercise induced damage and accelerate your recovery.

Note: In February 2012, Bayley et al. published a paper that shows that the application of passive heat in form of a 42°C hot water bath for 40min immediately prior to a bout of HIT leg extensor exercises reduced the time to fatigue in seven healthy men by a whopping -36%  (Bayley. 2012). Impatience, or rather the unwillingness to grant your body the time it needs to recover is thus detrimental even if the stressor is "just" a hot bath!

Whether the same would be true if you train today and do the hot water immersion immediately, 2h, 10h or 12h post and thus 48h, 46h, 38h or 36h before your next workout is yet about as questionable, as whether or not similar effects could be elicited by switching back and forth between light and heavy days every 48h.  Both may appear likely, but aside form the fact that the optimal timing or workout intensity will still have to be elucidated, are still in the state of an interesting research hypothesis, not more, but also not less.

Update - Suggested reading: Since there have been questions pertaining to the usefulness of hydrotherapy post-workout, i.e. as a means of "classic" re- and not "precovery", I thought I rather refer you directly to my buddy Sean's E-book on the issue. Here is a snippet from the book

Image 2: Don't miss Sean's free e-book on classic hydrotherapy

Quick Hit Summary Water therapy is a common modality to enhance muscle recovery post workout. Sitting in chest high thermoneutral water for 20-30 minutes may accelerate waste removal while increasing blood flow to working muscles. Cold, hot and contrast water temps are also commonly used to assist recovery. The goal of cold water therapy is to reduce inflammation whereas hot water purportedly increases muscle blood flow. Contrast water therapy involves alternating between hot and cold water baths to induce a vaso-pumping effect. Current evidence does not support the theory behind these latter 2 therapies simply because the heat (from the water) is incapable of penetrating more than a couple centimeters into the skin. Thus, there is no stimulus to increase muscle blood flow

You can get this e-book alongside two other books for free if you register for Sean's newsletter, which is, take my word on it (!), not a weekly advertisement piece!
 
References:

1. Bailey SJ, Wilkerson DP, Fulford J, Jones AM. Influence of passive lower-body heating on muscle metabolic perturbation and high-intensity exercise tolerance in humans. Eur J Appl Physiol. 2012 Feb 10.
2. Briese E. Normal body temperature of rats: the setpoint controversy. Neurosci Biobehav Rev. 1998 May;22(3):427-36. Review. 
3. Frier BC, Locke M. Heat stress inhibits skeletal muscle hypertrophy. Cell Stress Chaperones. 2007 Summer;12(2):132-41. 
4. McArdle A, Dillmann WH, Mestril R, Faulkner JA, Jackson MJ. Overexpression of HSP70 in mouse skeletal muscle protects against muscle damage and age-related muscle dysfunction. FASEB J. 2004a Feb;18(2):355-7.
5. McArdle F, Spiers S, Aldemir H, Vasilaki A, Beaver A, Iwanejko L, McArdle A, Jackson MJ. Preconditioning of skeletal muscle against contraction-induced damage: the role of adaptations to oxidants in mice. J Physiol. 2004b Nov 15;561(Pt 1):233-44. Epub 2004 Aug 26.
6. Pumpa KL, Fallon KE, Bensoussan A, Papalia S. The effects of Lyprinol(®) on delayed onset muscle soreness and muscle damage in well trained athletes: a double-blind randomised controlled trial. Complement Ther Med. 2011 Dec;19(6):311-8.
7. Touchberry CD, Gupte AA, Bomhoff GL, Graham ZA, Geiger PC, Gallagher PM. Acute heat stress prior to downhill running may enhance skeletal muscle remodeling. Cell Stress Chaperones. 2012 May 17. [Epub ahead of print]