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marylin monroe
Showing posts with label GH. Show all posts
Showing posts with label GH. Show all posts

Add Two Pounds of Lean Mass in Three Weeks W/ HIIT. HIIT Sprint Training Builds Muscle & Anaerobic Power While Reducing the Exercise Induced GH Response by 64%

HIIT - A GH diminishing mass builder?
I know it sounds contradictory, at first. If you take into considerations that previous studies show that the post-exercise increase in growth (and other) hormones does not correlate with the beneficial adaptational effects of exercise, it's actually no longer that surprising that researchers from the Department of Exercise Physiology at the Winston-Salem State University found that "[o]ne week of HIT significantly decreased GH release, with a simultaneous significant increase in anaerobic power and lean body mass of the lower extremities." (Ritsche. 2014)

In their latest paper which appeared in the December edition of the Journal of Exercise Physiology Kevin Ritsche, Jason Smith, Paul Mellick, and Laurie Wideman report the results of a recent experiment in the course of which 19 recreationally active male subjects (24.9 ± 3.9 yrs) completed a one-week high intensity interval training.
You can learn more about HIIT at the SuppVersity

Never Train To Burn Calories!

Tabata = 14.2kcal /min ≠ Fat Loss

30s Intervals + 2:1 Work/Rec.

Making HIIT a Hit Part I/II

Making HIIT a Hit Part II/II

HIIT Ain't For Everyone
The training protocol used in the study was based on similar high-intensity protocols published by Burgomaster et al. (2005) and Gibala et al. (2006) and began 24 hrs after the completion of a pre-test that was designed to measure the baseline fitness, body fat and lean body mass (by DEXA), as well as the acute GH response to high intensity exercise in the 19 young subjects.

The training protocol consisted of 4 to 6 repetitions of 30-sec maximal sprints and was performed three times per week for 3 weeks. One day of rest intervened each training session.
"The first 3 training sessions consisted of four 30-sec repetitions at 7.5% body mass with 4 min of active recovery at 50 W between each repetition. Training sessions 4 to 6 (wk 2) consisted of 5 repetitions, and sessions 7 to 9 (wk 3) consisted of six 30-sec maximal repetitions. During each repetition, each subject was encouraged verbally to provide maximal effort" (Ritsche. 2014).
At the end of each week, 48 hrs after the third training session for the week, subjects completed the acute sprint test protocol outlined previously (including blood draws).
Figure 1: Changes in body composition in response to the 3-week hiit-training protocol. the percentages above the bars indicate the relative difference between pre- and post-value. The light bars tell you that the corresponding changes were not statistically significant (Ritsche. 2014).
At least 48 hrs after the final blood profile, a post-training DXA scan was completed as outlined previously.
Figure 2: (a) Peak power; (b) peak power-corrected for subjects’ body mass; and (c) fatigue index during each 30-sec maximal cycle ergometer acute sprint (as) before and after 3 wks of hit; and (d) total combined workload of every sprint during each training week (Ritsche. 2014)
As you can see in Figure 1, the DXA-scans revealed significant increases in total and leg lean mass, albeit only non-significant reductions in body fat - changes which went hand in hand with a profound increase in exercise performance (see Figure 2) and a significant reduction of the initially observed post-exercise growth hormone spikes (see Figure 3).
Figure 3: Peak growth hormone concentrations after the workouts during the pre-test and after 1, 2 & 3 weeks of training; %-ages indicate difference to pre-value (Ritsche. 2014).
Bottom line: If you take into consideration that there is a close association between the post-workout growth hormone release and the relative exercise intensity - i.e. relative to one's individual fitness level and the corresponding demands of the exercise - the amelioration of the growth hormone response could be a consequence of the adaptation process that occurred in the course of the three week intervention.

It is thus not necessarily a bad thing and does therefore not stand in contrast to the adaptational response Ritsche et al. describe in their latest paper. If you take another look at Figure 3 and compare the GH response to the adaptations in Figure 2, it rather indicates that the subjects got used to the exercise | Comment on Facebook!
References:
  • Burgomaster, Kirsten A., et al. "Six sessions of sprint interval training increases muscle oxidative potential and cycle endurance capacity in humans." Journal of applied physiology 98.6 (2005): 1985-1990.
  • Gibala, Martin J., et al. "Short-term sprint interval versus traditional endurance training: similar initial adaptations in human skeletal muscle and exercise performance." The Journal of physiology 575.3 (2006): 901-911.
  • Ritsche, Kevin, et al. "Acute Exercise-Induced Growth Hormone is Attenuated in Response to Short-Term, High-Intensity Exercise Training." Journal of Exercise Physiology (2014).

Arginine Blunts Growth Hormone Response to Resistance Training: Will the -41% Reduction in Post-Workout Growth Hormone Release Hamper Your Strength & Size Gains?

Arginine-based pre-workout products are more popular with guys than with girls. Could this be the reason that only women complain about unlovedly rapid muscle gains? ;-)
No, this is not a typo! The verb in the headline of today's SuppVersity article really is "to blunt", as in "to neutralize partially" (OED Online 2013). I have to admit that I was also surprised, when I spotted the study over in the "ahead of print" section of the International Journal of Sports Nutrition and Exercise Metabolism. Unless Forbes, Harber and Bell, of whom you will learn later that they've already conducted another 'arginine study', messed up, the results of their most recent experiment do yet leave little doubt: Arginine, an amino acid that is used to test the function of the GH-releasing somatotropic cells within the lateral wings of the anterior pituitary, does - when it is administered at a dosage of 0.075 g·kg-1 body mass right before an acute bout of resistance exercise (3 sets of 8 exercises, 10 repetitions at ~75% 1RM) attenuate the post-workout growth hormone surge in strength trained individuals (Forbes. Nov 2013).

You want more details? Here you go...

With ~5-6g of arginine being taken before a workout that consists of 3 sets of 8 classic strength training exercises that are performed for 10 repetitions and at an intensity ~75% of the personal 1RM of the 14 strength trained men [age: 25±4 y; body mass: 81.4±9.0 kg; height: 179.4±6.9 cm; and training experience: 6.3±3.4 y], the researchers from the Faculty of Physical Education & Recreation at the University of Alberta in Edmonton, Alberta, Canada designed an experimental setup which comes "shockingly" close to what the average and extraordinaire gymrat is doing, when he or she is hitting the grind.
Figure 1: Level of arginine, GHRH and IGF-1 at T = 0, 15, 30, 60 min of rest-recovery + integrated area under the curve for growth hormone (iAUC GH); all values expressed relative to placebo control (Forbes. Nov 2013)
Against that background the question whether you and the rest of the millions of hobby athletes who spend hundreds of bucks on pre-workout products every year have been hampering their own progress is, as hilarious as it may sound, not a totally unwarranted one. I mean, we can hardly ignore the statistically highly significant -41% reduction in total growth hormone secretion in the one hour "anabolic window" after the workout, Forbes and his colleagues measured - can we?

What do we make of these results?

Most of you will probably remember the often referenced results of West & Phillips, whose 12-week resistance training intervention in the course of which the researchers from the Exercise Metabolism Research Group at the Department of Kinesiology of the McMaster University in Hamilton, Ontario,  made the following observations (West. 2012):
  • Suggested Read: "Anabolic Workouts Revisited!" | more
    No correlations between GH, testosterone or IGF-1 and the lean mass gains of their 56 recreationally active young men, who were not actively participating in any weightlifting
    activities <8 months before the study.
  • Significant correlations between GH and the increase in type I (slow twitch, oxidative) muscle fibers, but no correlation between testosterone, IGF-1 and cortisol.
  • Significant correlations between GH, as well as cortisol and the increase in type II (fast twitch, gylcolytic) muscle fibers, but no correlation between testosterone and IGF-1.
Unlike Forbes, Harber and Bell in the study at hand, West and Phillips measured the hormone levels for up to 2h after the workout. It is thus possible, but in view of the progression of the GH levels in the Forbes study relatively unlikely, that we'd see a rapid increase in the 2nd hour of the rest period and thus an increase in the total amount of GH that's released in response to the combination protocol (arginine + exercise).

Is the decrease the result of a previous GH "overload"?

With respect to the possible involvement of an auto-negative feedback, which is another, previously suggested explanation for this phenomenon, of which I had to realize during my research for this article that it has been covered in the literature before (Kanalay. 2008), Forbes et al. remark that their data would basically exclude the possibility that "the GH suppression was not due to a GH or IGF-1 induced autonegative feedback loop." (Forbes. Nov 2013)

It may not be the perfect muscle builder and maybe not even something you want to take in the vicinity of a workout, but there is still promising data on the metabolic effects of arginine esp. for (pre-)diabetics | more
In other words, Forbes et al. exclude the possibility that the subjects experienced a rapid increase in growth hormone as we would see it in response to the intravenous injection of arginine (10x increase with 20g/m² surface area of the 12 normal men in a 1996 study by Rahim et al.) that would then have shut down the GH production just as the exogenous administration of steroids would shut down your natural testosterone production.

If we focus on the available data, the conclusion of the researchers from the University of Alberta is certainly right. If we do take into account that we are talking about post workout supplementation and remind outselves that "the somatotrope is also known to have a refractory period" (Kanaley. 2008), it should be obvious that post-workout measurements, alone, cannot exclude the possibility that the GH spike that's responsible for the auto-negative feedback occurred during, not after the workout.

In other words: Instead of focusing exclusively on the post-workout GH levels, Forbes, Harber and Bell would actually have had to measure the pre & intra-workout GH response, as well. The GH spike that would cause the auto-negative feedback could after all have been caused by a sudden drop in blood glucose in response to the insulin sensitizing effects of arginine and the 'glucose hungry' strength training session.

Auto-negative feedback is still possible, but isn't there something else?

An alternative explanation for the lowered growth hormone response may come from a closer reading of the 'prequel' to this study. In January, Forbes et al. published a paper with the same supplement, but a different exercise protocol. Instead of hitting the weights, their 15 aerobically trained male subjects cycled for 60 min at 80% of their personal VO2max - again, immediately after ingesting 5-6g of l-arginine (0.075g/kg body weight).

Is there anything arginine is good for, if it's not a muscle builder and it's effects on nitric oxide are overblown? There is a previous SuppVersity article that would suggest so: "Arginine a BAT Building WAT Killer & Repartitioning Agent?" | more
Contrary to the strength training routine, the (relatively) high intensity cycling had identical effects on the hormonal, metabolic and cardio-respiratory markers of the subjects, the two things that differed, though, were
  • the rate of fatty acid oxidation at the onset of the workout, which was reduced in the l-arginine group, and
  • the levels of the sugar alcohol glycerol at the 45-min time point, which were slightly, but significantly increased
These observations stand in line with the effects McConell et al.  observed in a 2006 study in response to the infusion of l-arginine.

The arginine infusion increased the glucose uptake and blunted the increase in nonesterified fatty acid and glycerol concentrations during 120min of cycling at 72% of the VO2max which were followed immediately by a 15-min "all-out" cycling performance bout (McConell. 2013). Whether it also changed the GH response is however something I can't tell you, because reseachers from the The University of Melbourne did not measure the effect the arginine infusion had on the growth hormone levels of their study participants. I would yet guess that it will have been similar to the one on the cycling study Forbes did. This, in turn, would suggest that the effect depends on (a) duration and energy expenditure, or (b) the substrate utilization during the workout (lifting weights = glycolytic; cycling = rather oxidative). In the end both of these are related to the reliance on fat, not glucose / glycogen to fuel the energetic demands of your workout and as you all know the acute provision of  glucose is the prerogative of glucocorticoids (i.e. cortisol), not GH.
There may be another reason arginine does not make you "big": It's one out of three amino acids that have an especially pronounced satiety effect | learn about the others!
I can't exactly tell you why, but I can tell you that... I openly admit that I was surprised by the results of the study at hand. I  surprised that I missed this (side) effect of arginine, before, but I am not worried that the arginine supplements you may be or may have been taking are / were  hampering your training success.

 If that was the case one of the many "real-world" arginine supplementation studies, where the study outcome wasn't some funky hormonal marker of which we still don't know whether / to which extent it actually affects skeletal muscle hypertrophy, would have shown a trend for decreasing performance, lean mass and strength gains with arginine supplementation - this, I can assure you was not the case.

In fact, those of you who remember one of my posts on the 'arginine powered' VPX preworkout products (learn more), will remember that the scientists observed, if anything, opposing, i.e. beneficial effects from complex preworkout products as most of you will be using. A somewhat different picture emerges for the 'arginine only studies' where "only" three out of five acute supplementation and four out of eight chronic supplementation studies showed measurable, but in many cases negligible performance gains (Alvares. 2011). And the null-effect the authors of the other papers observed is no reason to be concerned, either.
References:
  • Álvares TS, Meirelles CM, Bhambhani YN, Paschoalin VM, Gomes PS. L-Arginine as a potential ergogenic aid in healthy subjects. Sports Med. 2011 Mar 1;41(3):233-48.
  • "blunt, v.". OED Online. September 2013. Oxford University Press. http://www.oed.com/view/Entry/20664?rskey=iZQVcA&result=3&isAdvanced=false (accessed November 19, 2013).
  • Forbes SC, Harber V, Bell GJ. The acute effects of L-arginine on hormonal and metabolic responses during submaximal exercise in trained cyclists. Int J Sport Nutr Exerc Metab. 2013 Aug;23(4):369-77. Epub 2013 Jan 8.
  • Forbes SC, Harber V, Bell GJ. Oral L-Arginine Prior To Resistance Exercise Blunts Growth Hormone in Strength Trained Males. Int J Sport Nutr Exerc Metab. 2013 Nov 13. [Epub ahead of print]
  • Kanaley JA. Growth hormone, arginine and exercise. Curr Opin Clin Nutr Metab Care. 2008 Jan;11(1):50-4. Review.
  • McConell GK, Huynh NN, Lee-Young RS, Canny BJ, Wadley GD. L-Arginine infusion increases glucose clearance during prolonged exercise in humans. Am J Physiol Endocrinol Metab. 2006
  • Rahim A, Toogood AA, Shalet SM. The assessment of growth hormone status in normal young adult males using a variety of provocative agents. Clin Endocrinol (Oxf). 1996 Nov;45(5):557-62.
  • West DW, Phillips SM. Associations of exercise-induced hormone profiles and gains in strength and hypertrophy in a large cohort after weight training. Eur J Appl Physiol. 2012 Jul;112(7):2693-702.

Differences in Growth Hormone, Insulin and IGF-1 Response in Trained and Untrained Resistance Trainees - Further Evidence That GH Builds Neither Muscle Nor Strength

Image 1: Rookie (top) or veteran (bottom, Jack Lalanne), their hormonal response to push-ups is different, but does not explain the different outcomes of strength training.
If you are a regular, here at the SuppVersity, you will have hear me lament the fact that in many of the mainstream studies on the effects of exercise on body composition, endocrine parameters and so on, the study participants are either sickly, obese or both... admittedly, whenever measures of muscle hypertrophy are involved, the subjects are usually healthy rookies, which is by  no means better, as you all know from your first weeks in the gym that, despite doing everything wrong, your strength and size gains were tremendous. Now, the obvious question is, are the endocrine adaptations / responses distinct, as well? According to the results of a recent study by Rasani Ranjbar et al. they are (Hasani-Ranjbar. 2011) - surprisingly, though, on paper, the endocrine milieu of the veterans appears more conducive to strength and size gains than that of the rookies... but let's take a look at the actual results, before we even start discussing their implications.

The Iranian scientists recruited 15 previously strength trained and 19 untrained male (how else could it be in this lovely country?) students at the Tarbiat Moallem University, divided them in an experimental (trained) and a control group and took blood samples at 10am (pre-test) after the students, who had arrived at the lab at 7am, had been served identical breakfasts (at 7:30-8:00am). Subsequently, the training groups (E1 = previous strength training experience; E2 = rookies) performed a resistance training protocol at 70-80% of their maximum strength in the 10-12rep range (i.e. a classical "hypertrophy training"), consisting of 4 sets of chest presses, stretch wires [I have no clue what kind of Iranian specialty that is], leg extensions and leg curls to failure with rest times of 2 minutes in between sets and 4 minutes between exercises.
Figure 1: Training induced changes in growth hormone (GH) compared to untrained control (Hasani-Ranjbar. 2011).

Blood was drawn at four timepoints: pre-test (T1), immediately after cessation of the exercise session and before lunch was served (T2), five hours post training (T3) and seven hours post training (T3). The samples were analyzed for growth hormone (GH), insulin, insulin-like-growth-factor 1 (IGF1), IGF1 binding protein 1 and 3 (IGFBP1 & IGFBP2). I have plotted the relevant data (i.e. data where you see meaningful changes) in figures 1 & 2.
Figure 2: Training induced changes in insulin and IGF1 compared to untrained control (Hasani-Ranjbar. 2011).
Now, what do we make of these results? Obviously the immediate GH response to resistance training is more profound in the veteran group, it is yet more sustained in the rookies, whose insulin levels interestingly skyrocket in the late post exercise period, yet in the absence of any significant increases in IGF1 levels (the same was true for the binding proteins) over the untrained control group.
Figure 1: Absolute IGF1 levels (in ng/ml) in trained and untrained rookies and veterans (Hasani-Ranjbar. 2011).
I don't know which data the Iranian scientists analyzed, but despite the fact that there is as they state a steady decline in IGF1 this probably isn't a result of the strength training regimen (as the Iranians would have it) but simply related to the lack of food intake in the 5-7h post lunch, which was ingested right after the post blood draw, i.e. exactly 5 hours before the 5h post blood was drawn....

Be that as it may, the more relevant result is that there may be differences in the endocrine response to exercise, but those are exactly contrary to what we would have to see, if the highly marketable GH increase, you are supposed to spike with all sorts of supplements had any effect on your gains in the gym. After all, you bet that if any of the two groups had had measurable strength or size increases at a subsequent training session / body composition measurement, it would have been the rookie group. That being said, this study further supports the position of the Phillips group from McMaster University (cf. Arms Don't Grow Faster with Prior Leg Training), who maintain that the exercise induced GH increase has absolutely no effect on strength or size gains... in other words, spending money on respective supps or focusing on training techniques that have been shown to increase GH (and have not been shown to be productive in terms of size and strength gains) is not advisable.

IL-6 - True Muscle Builder or Just a Measure of Workout Intensity? Plus: If Testosterone Does Not Matter, Why Does the Androgen Receptor Density Make a Difference?

No matter how close we look, the influence of previous, i.e. GH, IGF-1 and testosterone, as well as novel, i.e. IL-6 and AR expression, potentially growth promoting suspects remains elusive.
SuppVersity readers know, there is more to "inflammation" than the average mass media article will make you believe. The same "bad cytokines" that will decrease your insulin sensitivity, make you sick and obese, when they leak from your "inflamed" beer belly, are actually the good guys, when they are released in response to a workout from the musculature. "Myo-", not "cytokines", that's how researchers refer to them (Pedersen. 2007); and their role in (exercise) metabolism and immunity is until now still not fully understood.

The results the scientists from the McMaster University probably won't add much to our understanding of the systemic effects of IL-6 and other myokines. What certainly do, though, is to support the notion that "inflammation" can have profound and very far-reaching effects on our physiology (learn more).

Does IL-6 build muscle?

The mere idea that IL-6, a molecule of which most people think that it was a good measure of how messed up your health actually is, could be a promoter, or at least a measure, of skeletal muscle growth in response to a workout sounds about as logical (or illogical, if you will) as the previously established fact that the allegedly anabolic hormones testosterone, IGF-1 and growth hormone don't show the slightest correlation with the exercise induced skeletal muscle growth (West. 2011; learn more in "Anabolic Workouts Revisited").
Figure 1: Relative increase in muscle CSA change for androgen receptor density and p70S6K expression (left) and individual correlation of endocrine changes and muscle CSA (right), data based on Mitchel. 2013)
What was to be expected, though, was the correlation between the skeletal muscle hypertrophy response to the 16 week / 4x per week exercise program the 23 previously untrained study participants had to endure, on the one hand, and the exercise induced increase in p70S6K, on the other hand. The signalling protein p70S6K is after all something like the "protein pump"-gauge in the mTOR cascade.

Strength training can increase the androgen receptor density

Less well-known, but also not really new is another observation Mitchel et al. made: The resistance training lead to an allegedly subject specific and overall insignificant increase in the density (number per area unit) of androgen receptors; and though the overall increase may not have been statistical significant, the correlation of the the increase in androgen receptor density and the lean muscle gains of the subjects was.
New myonuclei (blue) are necessary to keep growing (learn more)
What about the muscle structure? What I am missing in this study is a measure of the myonuclei and domain sizes. We know that inflammation plays a major role in the restructuring process of the musculature that's necessary to maintain myonuclear domain size and thus the capacity for muscle protein synthesis (Bamman. 2001). It does furthermore seem likely that the any increase in myonuclei number would go hand in hand with increases in the number of androgen receptors. The corresponding data could thus help us to answer some of the questions we still have about the immediate (mTOR) and the chronic (endocrine and immune) contributions to skeletal muscle hypertrophy.
Similar effects on the androgen receptor density have been described by Willoughby & Taylor in 2004, already. In the pertinent study from the Baylor University, this increase did yet go hand in hand with increases in total testosterone and the free androgen index, of which the authors say that they were brought about by persistent increases in testosterone - increases in testosterone that were not observed in the more recent study by Cameron Mitchel, where the testosterone levels dropped (albeit non significantly) in response to the 2x2 upper-/lower-body split training.
"Our study corroborates previous findings that mean AR protein expression was not increased following resistance training; however, the response had marked heterogeneity, with some subjects showing a marked (1.5 - 2.5 fold) increase in AR protein content [...] Despite no statistically significant change in AR receptor protein content, there was a correlation between AR protein content with fibre hypertrophy. Our results suggest that changes in AR content may be part of a muscle-specific response present to a greater degree in responders and responsible for some (~25%) of the variation in muscle fibre hypertrophy." (Mitchel. 2013)
With regard to the correlation (I want to emphasis that we don't have enough evidence to do anything, but speculate about causative effects, here), it may be worth mentioning that the statistical significant association between androgen receptor density and the changes in muscle cross-sectional area was more pronounced in the "strength type" fast twitch (type II) than in the "endurance type" slow twich muscle fibers (0.6, p = 0.002 vs. 0.47, p= 0.023).

For IL-6, on the other hand,  it was the exact opposite. Unlike the number of androgen receptors per muscle area, the amount of interleukin 6 that was released or, as Mitchel et al. say, "filtered" from the muscle into the blood stream in response to the workout exerted a minimally more pronounced effect on the slow twitch "endurance type" fibers (type II).
So is IL-6 anabolic? It is counter-intuitive and would be premature to say that "IL-6 plays a causal role in skeletal muscle hypertrophy". This is particularly true in view of the fact that high baseline IL-6 levels that would be indicative of chronic vs. acute inflammation were "inversely correlated with fibre hypertrophy" and that IL-6 per se "is associated with both muscle protein breakdown and JAK/STAT signalling in satellite cells" (Mitchel. 2013).

Acutely (green circle) IL-6 will help build muscle, chronically it will make you sick (Muñoz-Cánoves. 2013).
It does thus appear to be more likely to assume that the increased IL-6 response is - just as the previously observed increase in cortisol in West et al. (2011), by the way - a marker of the workout induced strain, which does - in a non-overtraining scenario! - predict the adaptive response and thus the actual muscle gains.

The fact that the inclusion of IL-6 in a model prediction of the exercise induced hypertrophy response did not increase its accuracy would also point towards a corollary, not a causal involvement of a cytokine, the local (=in the muscle) production of which has also been implicated in the protective effect of exercise against insulin resistance, as well as increases in lipolysis and fatty acid oxidation (Pedersen. 2007).

In the end I have to admit that the study at hand does not really offer the material that would be necessary to formulate something like practical implications. What the results Mitchel et al. present in their paper can do is to reaffirm that skeletal muscle hypertrophy occurs in a(n at least) bi-phasic process with (1) an acute "inflammatory" phase where P70S6K (part of the mTOR cascade) determines and IL-6 (and thus inflammation) correlates with an increase in lean muscle mass and (2) a long-lasting "recovery" phase where the increase expression of androgen receptors could play an important role in the maintenance of the immediate gains in skeletal muscle protein. Your training should thus provide for both: An intense hypertrophy stimulus on the training days and lots of time and nutrients to recover on your off days.
References: 
  • Bamman MM, Shipp JR, Jiang J, Gower BA, Hunter GR, Goodman A, McLafferty CL Jr, Urban RJ. Mechanical load increases muscle IGF-I and androgen receptor mRNA concentrations in humans. Am J Physiol Endocrinol Metab. 2001 Mar;280(3):E383-90
  • McKay BR, De Lisio M, Johnston AP, O'Reilly CE, Phillips SM, Tarnopolsky MA, Parise G. Association of interleukin-6 signalling with the muscle stem cell response following muscle-lengthening contractions in humans. PLoS One. 2009 Jun 24;4(6):e6027. 
  • Mitchell CJ, Churchward-Venne TA, Bellamy L, Parise G, Baker SK, et al. Muscular and Systemic Correlates of Resistance TrainingInduced Muscle Hypertrophy. PLoS ONE. 2013; 8(10): e78636
  • Muñoz-Cánoves P, Scheele C, Pedersen BK, Serrano AL. Interleukin-6 myokine signaling in skeletal muscle: a double-edged sword? FEBS J. 2013 Sep;280(17):4131-48. doi: 10.1111/febs.12338. Epub 2013 Jun 18.
  • Pedersen BK, Akerström TC, Nielsen AR, Fischer CP. Role of myokines in exercise and metabolism. J Appl Physiol (1985). 2007 Sep;103(3):1093-8. Epub 2007 Mar 8. Review.
  • West DW, Phillips SM. Associations of exercise-induced hormone profiles and gains in strength and hypertrophy in a large cohort after weight training. Eur J Appl Physiol. 2012 Jul;112(7):2693-702. doi: 10.1007/s00421-011-2246-z. Epub 2011 Nov 22.
  • Willoughby DS, Taylor L. Effects of sequential bouts of resistance exercise on androgen receptor expression. Med Sci Sports Exerc. 2004 Sep;36(9):1499-506.

The Female(?) Athlete Triad - Part II/III: LH, GH, IGF1, Insulin, Ghrelin, Leptin & Co Form a Self-Perpetuating Vicious Cycle

I usually rant against pizza and beer, but once the athlete triad has struck, they can be an occasional part of the "healing protocol".
In last Sunday's first installment of this series we have taken a look at the prevalence, etiology and fundamental cause of an entity that is, and I am repeating myself here, profoundly mislabeled as the "female athlete triad". In fact, it is, as we have learned in the last installment, neither an exclusively female thing, nor a triad. If anything, it is a quintet or sextet. To make that clear, and give you guys, who make the same mistakes, but usually with less detrimental consequences, I will once more refer to it as "athlete triad" = AT,  in this second part of the Female(?) Athlete Triad Series in which we will take a look at the endocrine underpinnings of the previously described consequences of the temporary and long-term energy deficiency we have identified as the single most important causative factor of the onset of the "triad" last Sunday.

Which endocrine factors are figuring, here?

Instead of overwhelming you with the details right from the start, I decided to compile a list based on a cross-section of the dozens of articles I have read in the course of my eventually futile quest for a single definitive answer to the question, "Which hormonal or metabolic consequence of restrictive eating and excessive training is to blame for the fatigue, the low sex hormones concentration,the  bone resorption, the anemia, the absence of menses / lack of libido, the performance decreases and the whole string of pathological features, we have explored in the last installment?"
"Refeeding is not an option, because you will only become fat!" FALSE! Yet another myth without substantial scientific foundation that probably arises from the disturbed self-perception of those affected by AT and AN. In fact, the fat stores are the last thing that will be restored (Golden. 2004). This is probably also one of the reasons why "refeeding" often does not appear to work, because the basal energy requirements will increase with every pound of lean tissue you add back to your frame, so that athletes suffering from the "triad" will have to continuously increase their energy consumption. Unfortunately, most athletes will fail to do the former (also because exercise & stress can blunt hunger) and instead react with an increase in workout intensity, now that they are finally able to work out, again. This, in turn, will restore or even exacerbate the energy deficit and thus worsen not improve their physiological problems, even if their scale shows that they have already gained 5-10kg. If you take a look at figure 1 you will also realize that, at least in women, a baseline level of total (not relative!) body fat appears to be necessary to maintain regular menses (in men to maintain normal total testosterone & SHBG, but not so much free testosterone levels or reproductive function).
  • low luteinizing levels are unquestionably among the elemental features and causally responsible for the occurance of menstrual disorders / lack of libido and the correspondingly low estrogen and testosterone levels in women and men
  • TSH levels are not a valid / reliable indicator for the presence of absence of AT, because they can be both slightly increased or normal in the presence of low T4 and low T3 levels, as  - and this is far more often the case - TSH can be low despite low free thyroid hormone levels (usually in the presence of a low T3/rt3 ratio; if anything this would be a good indicator of beginning or full-blown AT)
  • the circadian cortisol rhythm is whacked in men and women, alike; characteristic are the absence of an appropriate cortisol spike in the morning as well as the normal decline in cortisol levels  in the course of the day; metaphorically speaking, as the athletes triad progresses, the "mountain range" turns into mesa and eventually into a plane lowland
  • the quartet of (mostly) sub-clinical hypogylcemia, low insulin, extreme high / or totally blunted insulin sensitivity, low IGF-1 and high catecholamine levels cannot be seen in isolation, most detrimental are yet probably the first and last of these four glucose-related players in the AT concert, as the former entails the constant risk to run out of "brain fuel" (in the absence of alternative fuel sources) and can - in the absence of adequate corticosteroid expression - become potentially life-threatening and the latter, i.e. low IGF-1 levels and very low IGF-1 to IGF1 binding protein 4 being one of the, if not the central factor involved in the the long-term physical decline of muscle, bone, organ and even brain mass.
As I have repeatedly emphasized in the last installment, the underlying cause, the trigger, maintaining factor and thus most important setscrew of the athlete triad (female or male) is an over-exaggerated and / or  long-lasting (weeks to months, in the worst case years; see Sundgot-Borgen. 2000) discrepancy between energy intake and expenditure, your body will initially try, but eventually fail to compensate by
  • tapping into its energy stores in form of body fat, muscle and organ mass, the insulating fat around nerves and organs, etc.,
  • continuously decreasing its metabolic activity (esp. thyroid metabolism),
  • shutting down non-vital, but energy-intensive (e.g. immune and reproductive system) bodily functions, to prioritize short term survival of the individual over long-term survival and the conservation of the species
Therefore it is an indispensable and in many cases even sufficient prerequisite to restore an adequate supply of nutrients, and abolish temporarily better reverse the discrepancy between "energy in" and  "energy out" (please read the information in the red box next to the list of the previous paragraph, as well).

And what about leptin, ghrelin, adiponectin ... ?

Figure 1: In female athletes, only total fat mass, not body fat % or BMI are associated w/ AT (here identified by amenorrhea; top, left); the correspondingly low pulsatile (not baseline, see lower left) of LH correlate negatively with ghrelin and positively with leptin (top, right); while LH and leptin show a lack of pulsality, the ghrelin levels are not simply elevated, they also have a higher pulse size, amplitude and total polsatile secretion compared to control and eumenorrhetic athletes (bottom; LH, ghrelin, leptin expressed relative to non-athletic control; based on Ackerman. 2012)
Similar to the facilitative effects of the "hunger high", the "evolutionary advantage" that's turning its ugly face on everyone, who's willing to dig a deep enough whole (see Part I), the endocrine imbalances, as well as the reduced leptin) or over-pronounced (adiponectin) release of adipokines and the disturbances of the glucose, fatty acid and cholesterol metabolism start to take on a life of their own.

And as if that alone would not already make it difficult enough to separate cause and effect, it does actually appear likely that the order may even be reversed over time - not unlike the chicken that will hatch and eventually lay an egg. 

As discussed in the last installment, the combination of over-exercising and fasting, which may at time-point T0 actually have been the root cause of the problem will often turn into a strategy to stave off the impeding total breakdown. It becomes sort of a conditioned response to the constant starvation, which  will then no longer manifest itself in the form of hunger, but as anxiety and an almost compulsive urge to exercise (this is particularly well-established for anorexics; Teufel. 2008). And while the latter can be motivated by the desire to increase athletic performance and/or lose even more body fat, it does have a very real, often under-appreciated, physiological underpinning.

If you like, you could argue that the urge of the starved athlete to exercise is yet another "evolutionary conserved" automatism that mirrors the well-known food-seeking behavior rodents display  in periods of food deprivation and in response to the stimulatory effects of ghrelin on the orexin neurons in the brain (Yamanaka. 2003).

From ghrelin to growth hormone to IGF-1 and back

At the same time, the combination of exercise, low triglyceride, low free fatty acid and exuberant levels of the "hunger hormone" ghrelin leads to an overexpression of growth hormone (Scacci. 2003), subsequent increases in adiponectin (Wölfing. 2008), which will in turn decrease progesterone and androstenedione production and LH receptor expression in ovarian cells (Lagaly. 2008) and GnRH and LH release in the pituitary (Rodriguez-Pacheco. 2007; Lu. 2008). The surprisingly high adiponectin levels (surprisingly in view of the often dangerously low levels of adipokine producing body fat) will further increase the borderline pathological insulin sensitivity and thus lower the already rock bottom blood glucose and basal, as well as (post-)prandial insulin levels even further.
Figure 2: Illustration of the self-perpetuating vicious cycle of the athlete's triad (AT)
With their suppressive effect on leptin (Böni-Schnetzler. 1999), the high growth hormone levels and low body fat reserves are probably the most important contributers to the pathologically low, in fact quasi non-existent basal leptin secretion (see figure 1). And the low insulin levels don't just compromise the normal food-induced prandial suppression of ghrelin (Murdolo. 2003), they also hamper the production of IGF-1 (especially in the liver), so that athletes who suffer from the "triad" cannot derive any anabolic benefits from their high growth hormone levels, since the latter are largely mediated by the stimulatory effect of growth hormone on the production of IGF-1... what you are seeing here is thus a self-perpetuating vicious circle, you can extricate yourself from only by a multi-faceted approach the pillars of which are an..
* in view of the insulinogenic effects of whey and the pro-IGF-1 effects of casein (Hoppe. 2009), and the anti-catabolic effects of CLA & omega-3 you should - if by any means possible - incorporate dairy products from preferably grass fed dairy (butter, milk, cheese, yoghurt, quark / curd cheese, fermented dairy and if you want protein powders) in your diet regularly, better daily.
  1. adequate and continuous energy supply to control ghrelin levels and help stabilize blood sugar (and thus glucocorticoid) levels and restore normal leptin and adiponectin expression,
  2. increased low GI (to avoid reactive hypoglycemia) carbohydrate and protein intakes to normalize glucose levels, suppress ghrelin, increase insulin and IGF-1 levels* (Foster-Schubert. 2008; suggested read: "Carbohydrate Shortage in Paleo Land"),
  3. balanced intakes of all types of natural fats, with an emphasis on long-chain PUFAs from food including a reasonable amount of "bad" omega-6 fatty acids and w/out fish oil or other omega-3 supplements, which would further blunt the already compromised glucocorticoid response and the leptin secretion (Kratz. 2002; suggested read "Omega-3 and Low Cortisol"), and
  4. profound reductions in training volume to lower GH, cortisol, catecholamin and energy requirements and a (temporary) reorientation towards low volume strength training that will help increase bone density and IGF-1 expression (Davee. 1990)
Now, this may sound hilarious, but for the time being, laziness, pizza and beer - in moderation - are actually your friends. In that, I am not suggesting that you have to copy the patient, Chris Kresser mentioned several times on the old "Healthy Skeptic" podcasts (now RHR) about a client, who "cured" his longstanding physiological, and as I suspect psychological problems with pizza and beer, but the third pillar of this guy's regimen is actually a must: Go out with friends and start to enjoy your life again! Without thinking about food and exercise and sticking to whatever form of restrictive "diet" all the time.

Figure 3: Development of BMI (blue), leptin (red), adiponectin (green) levels in 8 female adolescent malnourished AN patients (based on Modan-Moses. 2007)
Apropos, third pillar. I have already had my short intense workout for the day, I have eaten well, but I have not hung out with friends. In other words, I will postpone the in-depth discussion of the energy and nutrient requirements, useful and detrimental supplements and medications, as well as necessary and facilitative tweaks to your workout routine to the next week, add another Roman "I" to the second "II" in "Part II/II" in the preliminary headline of this post and leave you (hopefully not too frustrated) with the graphical illustration of the effects re-feeding, alone, and a normalization of the body weight from a BMI of 16kg/m² to ~19kg/m² can have on the skewed basal leptin and adiponectin in figure 3.

In view of the fact that other studies have shown that this increase in weight, which must not be confused with a mere increase in adiposity, i.e. body fat percentage (go back to figure 1 if you already forgot that the absolute not the relative fat mass counts and please remember that the latter includes the fat in the myelin sheaths of your nerves, the protective fat around the organs, the fat in your brain etc.), does help with the normalization of both insulin and ghrelin (Otto. 2001), growth hormone and IGF-1 (Argente. 1997) and is in some cases even sufficient to restore most of the endocrine abnormalities (Scheid. 2010), many of the lessons we will learn in the next (and according to my current plans last ;-) installment can also be applied to a lean bulk - and that goes irrespective of your gender and your whether or not you have already fallen victim to the athlete triad!

References
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  • Argente J, Caballo N, Barrios V, Muñoz MT, Pozo J, Chowen JA, Morandé G, Hernández M. Multiple endocrine abnormalities of the growth hormone and insulin-like growth factor axis in patients with anorexia nervosa: effect of short- and long-term weight recuperation. J Clin Endocrinol Metab. 1997 Jul;82(7):2084-92.
  • Beals KA, Manore MM. Disorders of the female athlete triad among collegiate athletes. Int J Sport Nutr Exerc Metab. 2002 Sep;12(3):281-93. 
  • Boag F, Weerakoon J, Ginsburg J, Havard CW, Dandona P. Diminished creatinine clearance in anorexia nervosa: reversal with weight gain. J Clin Pathol. 1985 Jan;38(1):60-3. 
  • Böni-Schnetzler M, Hauri C, Zapf J. Leptin is suppressed during infusion of recombinant human insulin-like growth factor I (rhIGF I) in normal rats. Diabetologia. 1999 Feb;42(2):160-6.
  • Caspar-Bauguil S, Montastier E, Galinon F, Frisch-Benarous D, Salvayre R, Ritz P. Anorexia nervosa patients display a deficit in membrane long chain poly-unsaturated fatty acids. Clin Nutr. 2012 Jun;31(3):386-90.
  • Davee AM, Rosen CJ, Adler RA. Exercise patterns and trabecular bone density in college women. J Bone Miner Res. 1990 Mar;5(3):245-50.
  • Di Carlo C, Palomba S, De Fazio M, Gianturco M, Armellino M, Nappi C. Hypogonadotropic hypogonadism in obese women after biliopancreatic diversion. Fertil Steril. 1999 Nov;72(5):905-9.
  • Di Luigi L. Does the high performance athlete need hormone replacement? Endocrine Abstracts. 2012; 29: 35.1 
  • Foster-Schubert KE, Overduin J, Prudom CE, Liu J, Callahan HS, Gaylinn BD, Thorner MO, Cummings DE. Acyl and total ghrelin are suppressed strongly by ingested proteins, weakly by lipids, and biphasically by carbohydrates. J Clin Endocrinol Metab. 2008 May;93(5):1971-9.
  • Figueiro MG, Plitnick B, Rea MS. Light Modulates Leptin and Ghrelin in Sleep-Restricted Adults. International Journal of Endocrinology. 2012, Article ID 530726.
  • Golden NH, Meyer W. Nutritional rehabilitation of anorexia nervosa. Goals and dangers. Int J Adolesc Med Health. 2004 Apr-Jun;16(2):131-44.
  • Hernández M, Argente J, Navarro A, Caballo N, Barrios V, Hervás F, Polanco I. Growth in malnutrition related to gastrointestinal diseases: coeliac disease. Horm Res. 1992;38 Suppl 1:79-84.
  • Hobart J, Smucker D. The Female Athlete Triad. Fam Physician 2000; 61:3357-64,3367. 
  • Hoppe C, Mølgaard C, Dalum C, Vaag A, Michaelsen KF. Differential effects of casein versus whey on fasting plasma levels of insulin, IGF-1 and IGF-1/IGFBP-3: results from a randomized 7-day supplementation study in prepubertal boys. Eur J Clin Nutr. 2009 Sep;63(9):1076-83.
  • Khan KM, Liu-Ambrose T, Sran MM, Ashe MC, Donaldson MG, Wark JD. New criteria for female athlete triad syndrome? As osteoporosis is rare, should osteopenia be among the criteria for defining the female athlete triad syndrome? Br J Sports Med. 2002 Feb;36(1):10-3. 
  • Klok MD, Jakobsdottir S, Drent ML. The role of leptin and ghrelin in the regulation of food intake and body weight in humans: a review. Obes Rev. 2007 Jan;8(1):21-34.
  • Kratz M, von Eckardstein A, Fobker M, Buyken A, Posny N, Schulte H, Assmann G, Wahrburg U. The impact of dietary fat composition on serum leptin concentrations in healthy nonobese men and women. J Clin Endocrinol Metab. 2002 Nov;87(11):5008-14.
  • Lagaly DV, Aad PY, Grado-Ahuir JA, Hulsey LB, Spicer LJ. Role of adiponectin in regulating ovarian theca and granulosa cell function. Mol Cell Endocrinol. 2008 Mar 12;284(1-2):38-45.
  • Leibel RL, Rosenbaum M, Hirsch J. Changes in energy expenditure resulting from altered body weight. N Engl J Med. 1995 Mar 9;332(10):621-8. Erratum in: N Engl J Med 1995 Aug 10;333(6):399.
  • Loucks AB, Verdun M, Heath EM. Low energy availability, not stress of exercise, alters LH pulsatility in exercising women. J Appl Physiol. 1998 Jan;84(1):37-46.
  • Loucks AB. Energy availability, not body fatness, regulates reproductive function in women. Exerc Sport Sci Rev. 2003 Jul;31(3):144-8.
  • Lu M, Tang Q, Olefsky JM, Mellon PL, Webster NJ. Adiponectin activates adenosine monophosphate-activated protein kinase and decreases luteinizing hormone secretion in LbetaT2 gonadotropes. Mol Endocrinol. 2008 Mar;22(3):760-71. Epub 2007 Nov 15.
  • Manore MM. Dietary recommendations and athletic menstrual dysfunction. Sports Med. 2002;32(14):887-901. 
  • Mikos AE, McDowell BD, Moser DJ, Bayless JD, Bowers WA, Andersen AE, Paulsen JS. Stability of neuropsychological performance in anorexia nervosa. Ann Clin Psychiatry. 2008 Jan-Mar;20(1):9-13.
  • Miller SM, Kukuljan S, Turner AI, van der Pligt P, Ducher G. Energy deficiency, menstrual disturbances, and low bone mass: what do exercising Australian women know about the female athlete triad? Int J Sport Nutr Exerc Metab. 2012 Apr;22(2):131-8.  
  • Modan-Moses D, Stein D, Pariente C, Yaroslavsky A, Ram A, Faigin M, Loewenthal R, Yissachar E, Hemi R, Kanety H. Modulation of adiponectin and leptin during refeeding of female anorexia nervosa patients. J Clin Endocrinol Metab. 2007 May;92(5):1843-7. Epub 2007 Feb 27.
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  • Murdolo G, Lucidi P, Di Loreto C, Parlanti N, De Cicco A, Fatone C, Fanelli CG, Bolli GB, Santeusanio F, De Feo P. Insulin is required for prandial ghrelin suppression in humans. Diabetes. 2003 Dec;52(12):2923-7.
  • NCAA® Sports Sponsorship and Participation Rates Report • 1981-82 – 2010-11.  
  • Orlandi E, Boselli P, Covezzi R, Bonaccorsi G, Guaraldi GP. Reversal of bone marrow hypoplasia in anorexia nervosa: case report. Int J Eat Disord. 2000 May;27(4):480-2.
  • Ott V, Fasshauer M, Dalski A, Meier B, Perwitz N, Klein HH, Tschöp M, Klein J. Direct peripheral effects of ghrelin include suppression of adiponectin expression. Horm Metab Res. 2002 Nov-Dec;34(11-12):640-5.
  • Otto B, Cuntz U, Fruehauf E, Wawarta R, Folwaczny C, Riepl RL, Heiman ML, Lehnert P, Fichter M, Tschöp M. Weight gain decreases elevated plasma ghrelin concentrations of patients with anorexia nervosa. Eur J Endocrinol. 2001 Nov;145(5):669-73.
  • Rguibi M, Belahsen R. Body size preferences and sociocultural influences on attitudes towards obesity among Moroccan Sahraoui women. Body Image. 2006 Dec;3(4):395-400. Epub 2006 Sep 7.
  • Rodriguez-Pacheco F, Martinez-Fuentes AJ, Tovar S, Pinilla L, Tena-Sempere M, Dieguez C, Castaño JP, Malagon MM. Regulation of pituitary cell function by adiponectin. Endocrinology. 2007 Jan;148(1):401-10.
  • Scacchi M, Ida Pincelli A, Cavagnini F. Nutritional status in the neuroendocrine control of growth hormone secretion: the model of anorexia nervosa. Front Neuroendocrinol. 2003 Jul;24(3):200-24.
  • Scheid JL, De Souza MJ. Menstrual irregularities and energy deficiency in physically active women: the role of ghrelin, PYY and adipocytokines. Med Sport Sci. 2010;55:82-102.
  • Schtscherbyna A, Barreto T, de Oliveira FP; Luiz RR, de Abreu Soares RR, Gonçalves Ribeiro B. Age of onset training but not body composition is crucial in menstrual dysfunction in adolescent competitive swimmers. Rev Bras Med Esport. May/June 2012; 18(3).
  • Steinberg SE, Nasraway S, Peterson L. Reversal of severe serous atrophy of the bone marrow in anorexia nervosa. JPEN J Parenter Enteral Nutr. 1987 Jul-Aug;11(4):422-3.
  • Skarda ST, Burge MR. Prospective evaluation of risk factors for exercise-induced hypogonadism in male runners. West J Med. 1998 Jul;169(1):9-12.
  • Sundgot-Borgen J. [Physical activity and reproductive health]. Tidsskr Nor Laegeforen. 2000 Nov 20;120(28):3447-51.
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  • Williams NI, Helmreich DL, Parfitt DB, Caston-Balderrama A, Cameron JL. Evidence for a causal role of low energy availability in the induction of menstrual cycle disturbances during strenuous exercise training. J Clin Endocrinol Metab. 2001 Nov;86(11):5184-93.
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  • Yamanaka A, Beuckmann CT, Willie JT, Hara J, Tsujino N, Mieda M, Tominaga M, Yagami K, Sugiyama F, Goto K, Yanagisawa M, Sakurai T. Hypothalamic orexin neurons regulate arousal according to energy balance in mice. Neuron. 2003 Jun 5;38(5):701-13.

Trimethylglycine aka Betaine Sets the Anabolic Stage for Increased Muscle Growth: Higher IGF-1 & Lower Cortisol - Statistically Significant, but Physiologically (Ir-)Relevant?

Figure 1: Betaine content (in mg/100g) in some common food items (data based on Craig. 2004). Makes me wonder if Popeye ate wheat germ as well or whether he was celiac and stuck to spinach to get his daily dose of pro-anabolic betaine?
Trimethylglycine (TMG) the sciency name for a molecule most of you probably know by the name "betaine" is actually no longer a new-comer to the supplement scene (please note that this is not betaine HCL(!), the stuff you will find in digestive aids). I have already written about its purported ergogenic effects several times and there are actually quite a handful of proprietary blends with mostly undisclosed, but judged based on the total serving size and amount of ingredients in them, hilariously underdosed amounts of the zwitterionic compound and a methyl derivative of glycine in it on the market.

Friends and followers of the SuppVersity will also be aware that betaine is also found naturally in a variety of food sources such as sugar beets, wheat bran, spinach, shrimp, and many others (see figure 1) and that it can be synthesized from choline in your body, when dietary intake exceeds your current metabolic demands (Ueland 2011).

What you probably don't know, however, is...

... that the latest study from the Human Performance Laboratory at the Department of Kinesiology,
of the University of Connecticut, shows that "betaine (vs. placebo) supplementation enhanced
both the anabolic endocrine profile and the corresponding anabolic signaling environment, suggesting increased protein synthesis" (Apicella. 2012).
Figure 2: Effects of a standardized full-body workout (see text for details) on growth hormone (µmol/L), IGF-1 (nmol/L) and cortisol (µmol/L) levels in 12 recreationally trained young men after 2 weeks supplementation with betaine (2x 1.5g/day) or placebo (data based on Apicella. 2012)
And if we temporarily lose sight of the fact that the devil is in the detail, the data in figure 2 certainly looks as if you should run to the next best store with fishing equipment and get yourself a huge pot of trimethylglycine, of which the shop assistant will probably tell you that "This is a good choice Sir! The carps love the sweet taste!" But I am digressing, so let's get back to what's really sweet, namely ...
  • stable growth hormone levels (vs. -17% in the placebo group)
  • an 18% increase in IGF-1 (vs. a -10% decrease in the placebo group), and
  • a -5% reduction in cortisol (vs. a 6% increase in the placebo group)
- they all sound pretty sweet, as well. Especially in conjunction with the stable p-AKT levels the scientists observed, when they analyzed the tissue samples. Unfortunately (but earnestly), Apicella et al.'s conclusion, still contains one word, too many people who read the abstract, are probably going to ignore:
"Betaine (vs. placebo) supplementation enhanced both the anabolic endocrine profile and the corresponding anabolic signaling environment, suggesting increased protein synthesis." (Apicella. 2012; my emphases)
Which one is it? A tip: It is none of the words I emphasized in bold. After all, that would make it way too easy for you... ha? Yeah! I see you've done your homework. Suggest(-ing) is in fact the most important word in this and the conclusions of many objectively written scientific papers.

So, the study "suggests increased protein synthesis"...

... and this means it does not even prove that the protein synthetic response in the immediate vicinity of the workout was increased in response to the to the two weeks of BID (=twice daily) supplementation with 1.25 g of betaine. In other words, all we know is that the funky gene essays for p-AKT and serum tests for growth hormone, IGF-1 and cortisol "suggest" that it could be the case, if we assume that marginally higher IGF-1 levels, stable growth hormone levels and lower cortisol levels (rememeber we are not talking about increasing any of them into the supraphysiological range, here) would
  1. result in increased protein synthesis and ultimately
  2. greater lean mass accrual,
because, if we are honest, no one is interested in a number you can measure, when you infuse a marked amino acid into the circulation and check how much of it goes into the muscle, but doesn't come out of it, afterwards.

Something to remember: What I find remarkable - and this is by no means something you will see only in this study, neither is it "fraud" or whatever, is how by simply adding a break into the Y-axes of the graph and thus omitting the lower 80% of the bar Apicella et al. give the impression that the effects on IGF-1 were more than twice as large than they actually are... remember that, because you will encounter that in many studies, and reproductions of graphs from scientific papers, especially if they are used to market certain products.
What we want is to get bigger, stronger and all that faster, and whether the 12 recreationally trained men (age 19.7±1.2 years; lean body mass 65.2±8.8 kg; fat mass 15.6±8.5 kg; body fat percentage 18.7±7.0 %; BMI 28.2±4.0) would have gained even a single inch of muscle more on whatever body part, if they had performed a real workout instead of the funky "AES" (=acute exercise session) that consisted of
  • 10x maximal vertical jumps without pause, 
  • 1x 10-s isometric squat, 
  • 1x 10-s isometric bench press on a smith machine, and
  • 1x 10 min of repeated box lifting (RBL)
is more or less guesswork. In view of the previously discussed results from the researchers at the McMasters University in Ontario (see "Anabolic Workouts Revisited"; a brief reminder. the systemic hormonal response to an acute exercise bout is irrelevant, if anything higher cortisol levels correlate with greater increases in lean muscle mass) and the "statistically significant", but physiologically probably irrelevant increases and decreases in IGF-1 and cortisol at least highly questionably (please take a look at the additional information in the red box to the right, as well).

... but there are still way too many "ifs" in here!

The sheer number of "suggests", "is touted", "is likely", "also possible", "as we presume", etc. is honest and speaks in favor of the quality of the study, but against the reliability of the statement that followeed the initially cited "suggests" in the conclusion. Moreover, the researchers freely admit that...
"[...] the mechanisms by which betaine may have affected the hormones measured in this study are still unclear and require further research" (Apicella. 2012)
so that even the fact that betaine is an organic osmolyte and could thus help stabilize skeletal muscle protein, promote / maintain optimal hydration and protect against
  • hypertonic stress (Alfier. 2006), 
  • urea-induced inactivation of muscle myosin ATPases (Ortiz-Costa. 2002), and 
  • structural changes in myosin due to urea accumulation (Ortiz-Costa. 2002)
does lend credibility to the hypothesis that betaine could help you build muscle, but it does not prove it. In conjunction with the results of previous trials, like...
Betaine does not increase nitric oxide While I have no idea why everyone is so keen about those nitrate supplements, one thing is for sure: Betaine has no effects on serum nitrate or nitrite levels. The vasolidation effect of beet roots / beet root juice is simply a result of the nitrate that's in there along with the betaine (+ the sugar and the insulin spike, which will also trigger an increased NO-response).
At least this is what a study by Bloomer et al. which consisted of three independent experiments using 1.25 and 5.00g B, acutely, 2.5g per day for 14 days, chronically, and a combination of chronic (6g for 7 days) + acute (6g acutely before the test) betaine supplementation (Bloomer. 2011).
  • Hoffman. 2009 - 2.5/day for 14 days; jump squat, squat, bench press; "Two-weeks of betaine supplementation in active, college males appeared to improve muscle endurance of the squat exercise, and increase the quality of repetitions performed." 
  • Lee. 2010 - 2x 1.25g/day for 14 days; bench squat and jump tests; "[Betaine] supplementation increased power, force and maintenance of these measures in selected performance measures, and these were more apparent in the smaller upper-body muscle groups."
  • Hoffman. 2011 -  2.5g/day for 15 days; 5 training + testing sessions; "15 days of betaine supplementation did not increase peak CON or ECC force outputs during an isokinetic chest press but did appear to reduce subjective measures of fatigue to the exercise protocol"
  • Trepanoswki. 2011 - 2.5g/day for 14 days; resistance training; "moderate increase in total repetitions and volume load in the bench press exercise, without favorably impacting other performance measures."
  • del Favero. 2012 - 2g/day for 10 days; muscle strength and power, muscle PCr content, and body composition, three "familiarization sessions" preparing the participants only to perform the tests; "we showed that betaine supplementation combined or not with creatine supplementation does not affect strength and power performance in untrained subjects."
  • Pryor. 2012 - 2.5g/day for 7 days; cycling performance; "betaine ingestion significantly increased average peak power (3.4%; p = 0.026), maximum peak power max (3.8%; p = 0.007), average mean power (3.3%; p = 0.034), and maximum mean power (3.5%; p = 0.011) in recreationally active males and females"
... there is still room for long-term improvements in muscle gains as a consequence of the general ergogenic effects of betaine (every rep more counts!), but it appears unlikely that the "anabolic" hormonal milieu observed in the study at hand are the fundamental cause of the latter.

Reminder: If you want to try it, you got to get yourself "trimethylglycine" (TMG) not "betaine HCL" and you better don't buy it in capped form if you don't have lots of money to burn. I just checked with the next best bulk supplier - they got 1kg for $33.50. Even if you double dose, i.e. take 2x 2.5g per day (most studies mixed it with Gatorade) this will last you for 200days(!), which is probably the time it will take until you can actually see and not just measure any potential, possible, suggested, etc. anabolic effects ;-)

    References:
    • Alfieri RR, Bonelli MA, Cavazzoni A et al (2006) Creatine as a compatible osmolyte in muscle cells exposed to hypertonic stress. J Physiol 576:391–401.
    • Bloomer RJ, Farney TM, Trepanowski JF, McCarthy CG, Canale RE. Effect of betaine supplementation on plasma nitrate/nitrite in exercise-trained men. J Int Soc Sports Nutr. 2011 Mar 18;8:5.
    • Craig SA. Betaine in human nutrition. Am J Clin Nutr. 2004; 80: 539–549.
    • del Favero S, Roschel H, Artioli G, Ugrinowitsch C, Tricoli V, Costa A, Barroso R, Negrelli AL, Otaduy MC, da Costa Leite C, Lancha-Junior AH, Gualano B. Creatine but not betaine supplementation increases muscle phosphorylcreatine content and strength performance. Amino Acids. 2012 Jun;42(6):2299-305.
    • Hoffman JR, Ratamess NA, Kang J, Rashti SL, Faigenbaum AD. Effect of betaine supplementation on power performance and fatigue. J Int Soc Sports Nutr. 2009 Feb 27;6:7.
    • Hoffman JR, Ratamess NA, Kang J, Gonzalez AM, Beller NA, Craig SA. Effect of 15 days of betaine ingestion on concentric and eccentric force outputs during isokinetic exercise. J Strength Cond Res. 2011 Aug;25(8):2235-41.
    • Lee EC, Maresh CM, Kraemer WJ, Yamamoto LM, Hatfield DL, Bailey BL, Armstrong LE, Volek JS, McDermott BP, Craig SA. Ergogenic effects of betaine supplementation on strength and power performance. J Int Soc Sports Nutr. 2010 Jul 19;7:27. 
    • Ortiz-Costa S, Sorenson MM, Sola-Penna M (2002) Counteracting effects of urea and methylamines in function and structure of skeletal muscle myosin. Arch Biochem Biophys 408:272–278
    • Pryor JL, Craig SA, Swensen T. Effect of betaine supplementation on cycling sprint performance. J Int Soc Sports Nutr. 2012 Apr 3;9(1):12.
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