Intermittent Thoughts on Building Muscle: Understanding the "Big T" - Testosterone Programs Stem Cells to Become Muscle not Fat + Keeps Satellite Cells & Motoneurons Alive

Image 1: Graphical summary of the probably best known function of testosterone - including who are not so "profane" as building muscle and getting ripped ;-)

In the last two installments of the Intermittent Thoughts, I have tried to convey a realistic perception of what exactly the effects of both supra- (that is below) and super- (that is above) physiological (that is "normal" in the sense that they represent the "average" male human being) levels of testosterone on body composition are. In this installment of the series I am now going to provide more information on the "exact" molecular underpinnings by which testosterone works its muscle building and fat burning magic. There is however one thing related to data I presented in the previous installments, I want to emphasize again: The use of a testosterone enanthate in the Bhasin study makes it very difficult to use the data to make prognoses with regard to the results you would see, when you use natural (or unnatural) supplements to raise the endogenous (produced by your testes) production of testosterone. And although there are certainly dozens of factors that would preclude respective inferences, I am going to address only those three, of which I believe that they are the most significant ones.

Three things to keep in mind, when you interpret the data from the last installment(s):

1. With testosterone enanthate having a ~4-5 day half-life, the testosterone levels, which, in the Bhasin study, were measured on day 7 after the injection, represent only a <50% remainder of the testosterone levels we would see within 24 hours post injection.
   

   

   Figure 1: Hypothetical serum testosterone levels in the course of the first seven days after the injection of endogenous testosterone (blue) compared to the regular diurnal rhythm (green) and the levels in response to a pretty potent (+70%) natural testosterone booster (red; all data has illustrative value, only)

   In spite of the fact that the data in figure 1 is obviously not based on "real" experimental data, I hope that by taking a brief look at the ratios of the areas under the curve of the
   
   
   • "normal" testosterone level with its ~40% daily variation (green), the...
      
   • +70% (maximally) naturally boosted testosterone level (red) and a ...
      
   • testosterone enanthate injection (blue),
      
   all of you will understand why the "muscle building / fat burning" effects of a +70% boost in testosterone from whatever OTC product you may be taking can hardly compare to injectable testosterone.
    
2. Another aspect that should be taken into account is the non-existent sex hormone binding globulin (SHBG) response in the Bhasin study, due to which the relative increases in bound and free (=unbound and purportedly "active") testosterone were identical. This can, but does not necessarily have to be the case, when you raise your testosterone levels "naturally". In that, the aromatization of testosterone to estrogen, appears to be one of the major correlates (I am deliberately not speaking of "causation" in this context) of increases in SHBG. In the worst case, you could thusly "boost" your total testosterone and end up with less free test due to a (possibly estrogen induced / related) increase in SHBG. That being said, I know a hand full of cases, where the exact opposite is the case. Especially very lean (yet still muscular) men tend to have low SHBG levels, so that despite "low-normal" total testosterone many of them have normal-high or even very high free testosterone levels.
    
3. The last factor that makes a direct quantitative comparison of the effects "naturally" and "artificially" elevated testosterone levels questionable, to say the least, is the absence of the natural diurnal rhythm with exogenous testosterone administration. In the course of 24h the testosterone levels fluctuate by +/-40% with a spike in the morning (around 6-7am) and a trough in the early evening. Contrary to the "artificially enhanced" testosterone levels, the ones on the printout from your lab thusly represent either the daily max (if the blood was drawn early in the morning), an average (blood drawn around noon) or the nadir (blood drawn in the evening) of your 24h testosterone level.
   Just as an aside: Imagine you wanted to sell a "natural test booster". What would be the best way to get a "clinically proven" rise in testosterone? Right! You just get your "study" participants tested in the evening for baseline and in the morning for post-intervention levels and *bang* you got your "clinically proven" +40% increase in testosterone ;-)
   And even if you managed (by whatever means) to "naturally" raise your testosterone to a level that you would "on average" have +200% the natural negative feedback mechanism (inhibition of luteinizing hormone (LH) release) will soon put an end to your thusly short-dated testosterone boost.

All that does yet not change the observation we have made in the first installment of this (hitherto) three-part series about the effects of testosterone on skeletal muscle hypertrophy: Testosterone builds muscle! The underlying physiological processes, however, are not fully elucidated. The brief summary I have put together in the following paragraphs is thusly a "work in progress" not only because I am still trying to figure out "how testosterone works", but also because the complex interplay of hormones, protein signalling cascades and key players of the immune system simply has not been fully elucidated, yet.

Direct effects of testosterone on muscle cells

I don't know if you have ever heard the name "Vida", if not, then you have probably not delved into the depth of bro-scientific steriodology. Julius A. Vida's book Androgens and Anabolic Agents was published in 1969 is what some people would call the "steroid bible". It contains information about the structure and biological activity of 666 different steroids.

Figure 2: Scan from Vida's book showing data on the androgenic and anabolic activity of 19-Nortestosterone (Nandronole, aka DECA) from a rodent model.

With the latter being of particular interest for roid / pro-steroid producers and consumers, scans of the tables, that make up a good part of the original book can be found on bulletin boards all over the Internet (cf. figure 2). Vida obtained the data from rodent studies and estimated the "anabolic" effect of the tested compounds based on the hypertrophy response of the levator ani muscle of his lab animals. Now, you may rightly ask yourself, how that relates to the topic at hand... well, the reason Vida (and most other researchers) chose the levator ani muscle as a benchmark is its high responsiveness to androgens, because it has a much greater androgen receptor (AR) density than the most of the skeletal muscle you are probably trying to build, when you are at the gym (well, I assume you don't train the levator ani, do you? ;-).

Image 2: The levator ani muscle is especially prone to androgen induced hypertrophy, because it has a particularly high amount of androgen receptors. Whether this is something you are particularly happy about or not, does not matter, in 99% of the cases that you read about the "anabolic activity" of a given "designer steroid", the latter is usually provided relative to the testosterone-induced hypertophy response of this muscle.

Interestingly, the areas of the muscle with the highest androgen receptor expression are the myonuclei and the satellite cells. You know both of them from previous installments of this series and will certainly remember that the recruitement of new myonuclei from satellite cells was a necessary prerequisite for continuous muscle growth, because with ever-increasing myonuclear domain sizes, the muscle will eventually become disfuctional (cf. "Growing Beyond Limits"). It is thusly likely to assume that, next to IGF-1, testosterone provides a second, secondary or complementary growth stimulus to the otherwise quiescent satellite cells. From the fact that the subjects in the Bhasin study exhibited a marked hypertrophy response in the absence of adequate training stimuli, we may also further conclude that the action of testosterone, contrary to the previously discussed locally expressed IGF-1 splice variants (cf. MGF & Co), does (at least up to a certain degree) not depend on muscle damage / strength training. The results of a 2005 study from the Human Performance Laboratory at the University of Connecticut (Kraemer. 2005), which found a -46% reduction in androgen receptor expression in response to volume (not single set, though) training, would even suggest, that testosterone takes a backseat, whenever the MGF-pathway is doing its muscle building job.

Whether the latter, i.e. testosterone's job in building muscle, is identical to the one of IGF-1 and its splice variants is debatable, anyways. After all experiments with isolated bovine satellite cells have shown that incubation with the synthetic androgen trenbolone lead to dose-dependent increases in protein synthesis and decreases in protein degradation (Kamango-Sollo. 2011). The function of testosterone could thusly be to maintain myoblasts (=progenitor cells) in the proliferate state - or, put more simply, testosterone keeps the satellite cells alive and ready to be incorporated into the muscle, whenever this becomes necessary.

Testosterone turns potential fat into muscle

Despite the fact that the muscle building effects of testosterone are at the heart of this series, I guess that you were similarly impressed by the effect the administration of graded doses of testosterone enanthate had on the body fat levels of the subjects in the Bhasin study. One possible explanation for this effect would certainly be the increased energy demands of the additional skeletal muscle mass. This alone can however hardly explain the profundity of the negative effects Bhasin et al. observed in the low and very low dose testosterone enanthate groups.

Figure 3: Relative change in lean and fat mass in response to changes in serum testosterone levels; the green area indicates "normal" = physiological testosterone levels; the asterisks (*) denote statistically significant (p < 0.05) changes vs. baseline (calculated based on Bhasin. 2001)

I mean, if you take a close look at the data, even the low-dose groups effectively gained some muscle mass (<2% and statistically non-significant). A loss of skeletal muscle mass thusly cannot explain the 18-37% increase in fat mass (cf. figure 3). In a subsequent publication Bhasin et al. thusly propose a - I may say quite exciting - alternative explanation for this and similar observations in hypogonadal men (Bhasin. 2004):

[...the] reciprocal change in lean and fat mass induced by androgens is best explained by the hypothesis that androgens promote the commitment of mesenchymal pluripotent cells into myogenic lineage and inhibit adipogenesis through an androgen receptor mediated pathway.

This priming effect testosterone has on the "universal" stem cells from connective tissue would not only result in a greater amount of stem cells that are to become muscle cells (in other words: satellite cells), testosterone would also reduce the amount of "future adipocytes" and thusly inhibit the formation of new and the replenishment of apoptotic, i.e. dead, fat cells. This hypothesis is corroborated by  recent findings of Semirale et al. who report that reduced visceral and subcutaneous fat accumulation with a reciprocal increase in lean mass in male mice with targeted androgen receptor over-expression in mesenchymal stem cells (Semirale. 2011).

The role of testosterone in the mind-muscle connection

Its effect on the actual muscle cells and their progenitors aside, testosterone also binds to the androgen receptors on the motoneurons that innervate the muscle. Interestingly, the death of these motoneurons, is considered the primary cause for sarcopenia and the associated decrease in muscle mass in the course of the aging process (Narici. 2008). Direct treatment of motoneurons with different doses of testosterone leads to increases in motoneuron size and number (Fraley. 2002; Mansouri. 2003). The physiological equivalent of the latter may thusly well be responsible for the improvements in the "mind-muscle connection" users of performance enhancing drugs frequently report. It may also facilitate a greater / optimized activation of existing muscle fibers and could thusly contribute to strength gains which would not depend on previous muscle growth. The increase in strength, in turn, would allow athletes to lift heavier weight and provide a novel growth stimulus, and so on...

Whenever there is talk of androgens and the "mind-muscle connection", someone usually mentions the three letters D, H and T and thusly invokes the role of the most potent androgen, dihydrotestosterone, to which the "Big T" is nothing but a prohormone. Whether it really is DHT, a combination of both, or if one is just more potent in inducing these androgen-related neuronal effects, will however be a topic for the next installment of this series,  in which DHT and estrogen will round out a still very sketchy portray of the complex role the "sex hormones" play in an orchestrate that is so complex that the notion that one hormone, protein, amino acid, or inflammatory cytokine alone could make your muscle grow is simply ridicolous - even if this hormone is "The Big T" ;-)

Training, Detraining, Retraining: Build Bigger and Stronger Muscles by Taking 3 Weeks Off!?

Image 1: This dog obviously knows how beneficial it is to take 3 weeks off and detrain. If we go by his physique, he did probably not realize that without (pre-)training and retraining the distinct line between detraining and laziness becomes as blurred - as blurred, by the way, as many it is for training junkies like me ;-)

I plead guilty! Guilty of not taking enough time off - against better judgment. In that, it is not the idea that I would "lose muscle" that urges me to the gym, it is not that I would be afraid to get fat and I could probably even stifle my desire to lift heavy objects, if it was not for the little man in my ear who keeps telling me: "Well, you won't get fat and you won't lose muscle, but think about it: You are fit, young and strong! Why waste your time idling around? Go for it hit the weights and let the veins pop" ... and alas, his words are too convincing to put my gymbag back into the locker and write one of the 237 blogposts I am constantly thinking about and never finding the time to compile. Thanks to Steven Arcera, who, by the way, is somewhat of the productive, digital counterpart of the little man in my ear, as he is constantly pricking new ideas into my brain by posting questions, links to studies and hypothesis on my Facebook wall, I do now have a scientifically validated counterargument that could (theoretically ;-) shut the small nag up... for 3 full weeks!

6 Weeks on, 3 weeks off, 6 weeks on OR 15 weeks on - what is more "productive"?

Aside from the longer, more in-depth articles here at the SuppVersity, the studies, we are dealing with on a daily basis are usually not older than max. 4 weeks. In view of the fact that even "Prof. Dr.", i.e. me, is only human, it sometimes happens that I a) either miss the publication of an interesting paper or b) file it under "candidates" and then forget about it... the latter happened with a study, Steven referenced in a brief discussion we had on facebook about "priming muscles for new growth". Since the results do however fit in pretty nicely with the concept of "skeletal muscle hypertrophy" I have been trying to establish in the course of the latest installments of the Intermittent Thoughts (yes, there will be a follow up on testosterone tomorrow ;-), I decided that it was about time to finally acknowledge the results of a May 2011 paper by Riki Ogasawara et al. (Ogasawara. 2011).

In their 15-week randomized trial, Ogasawara and his colleagues put 15 young (24.7y), previously untrained male subjects onto identical training regimen. In three supervised training sessions per week the subjects performed 3 sets of 10 reps at 70% of their predetermined 1-RM max. The latter was re-assessed every three weeks and the weight was adjusted appropriately. After 6 weeks of training 8 randomly selected subjects "had" to take 3 weeks off (retraining group), while the rest of the subjects kept their regular 3x per week training schedule (continuous group). At the beginning of week 9, the now "detrained" subjects resumed their training regimen, until after week 15, a final testing session was scheduled to provide the data we need to answer a question, of which I know that it already preys on your minds:  "Did the three weeks away from the gym compromise the progress in the retraining group?" 

Figure 1: Development of triceps brachii and pectoralis major CSA of the continuously training and the detraining/retraining group in the course of the 15-week study period (data adapted from Ogasawara. 2011)

If you take a cursory glance at the data in figure 1, the answer to this question must be "YES!" (I think I just heard the little man in my ear rejoice ;-) - there is no debating: the triceps cross-sectional area (CSA) of the continuous trainers grew 2.4% more, the pectoralis major even 5.7% more, but with the given standard deviations of >7% and >10%, the little man in my ear will be having a hard time to convince me that I would miss out on muscle gains, when I took three weeks of - and that, even if I were a bloody beginner.

If we now assume that with my reluctance to take even a complete week off, my size gains would already have reached the "quasi-plateau" that is situated to the right of the logarithmic graph which describes the CSA development of the continuous training group, one could even make an argument that I and any other advanced trainee, whose gains have been slowing down over the last couple of weeks, would see an even more profound "growth boost" after 3 weeks of detraining, than the previously untrained subjects in the Ogasawara study. In fact, the increase in the amount of muscle mass I  would be able to accrue per week, might not only compensate (within the statistical margin ;-), but rather surpass the gains I thought I constantly fear I could "miss" during my off time.

Figure 2: Development of bench press 1RM strength and triceps brachii maximum voluntary contractive force of the continuously training and the detraining/retraining group in the course of the 15-week study period (data adapted from Ogasawara. 2011)

Moreover, the fact that the strength gains, in general, and the maximum voluntary contractile force the subjects were able to apply to a Biodex dynamometer with their elbow extensors, in particular, exhibit similar or even smaller differences (cf. figure 2), provide additional arguments by the means of  which I could probably convince myself that detraining is not for retiring athletes only.

Figure 3: Development of bench press 1RM strength (left) and triceps brachii maximum voluntary contractive force to triceps brachii CSA ratio (data adapted from Ogasawara. 2011)

And if that is still not enough to lay aside the dumb- and barbells for at least 2 weeks (you see I am negotiating again ;-), I could make a point that I do not only want to look strong, but also want to be strong; and as the right graph in figure 3 shows quite clearly, the three-weeks detraining period lead to 2.3% larger, yet again statistically non-significant increase in the pound per pound force production of the triceps muscle of the study participants in the retraining group.

Detraining is neither for pussies nor for retiring athletes, only

I guess, the foregoing subheading, summarizes the main take-away message of the study quite nicely. In view of the non-existent loss in muscle mass and strength in the course of the detraining period and the subsequent "growth spurt" (relative steep linear vs. leveled logarithmic increases in weeks 9-15), it should be obvious that the incorporation of strategic detraining periods into your training schedule is more than a welcome opportunity for laziness (something that totally turns me off, btw.). It is rather a phase where the reconstruction processes you have learned about in the Hypertrophy 101 and the subsequent installments of the Intermittent Thoughts will carve the way for future gains. Whether this will suffice to soothe the little man in your ear, I don't know... maybe you can negotiate a 2-weeks detraining period for the start ;-)

A Tale of Macro- & Micronutrient Modifications: Eating "Unlimited Protein" Will Make You Fat. A Hypercaloric Low Protein Diet With a Large Amount of Arginine Won't!

Image 1: The main message of the Bray study (according to Bray himself is) that you won't get away with consuming way more energy than you need - no matter how much of this energy comes from protein.

Even if you have not read it on the SuppVersity Facebook page, or in the comment section of one of the previous posts, I am sure that most of you all will have heard, or rather read, the fuss people have been making about getting away with "eating unlimited amounts of protein". Now, although, I know that you, as an educated SuppVersity reader would not fall for b***s*** like this, I still feel inclined to at least refer you to the surprisingly good summary, Dr. George A. Bray, the author of the study which triggered the recent upheaval (Bray. 2011), provides in his JAMA Video interview on YouTube. The main take home message you should remember is: "Fat gain is primarily a function of calories" - the subjects in all three groups (5%, 15% and 25% protein) gained, within the statistical margin of error, the same amount of body fat.

The nitty gritty on overeating: Eat 140% of the energy you expend and get fat - no matter what!

The one difference a higher protein intake on a hyper-caloric diet makes - and I am certain that you will have been aware of that - is that overeating on protein will help stimulate muscle protein synthesis and thusly facilitate increases not only in fat, but also in lean mass. Now, while this obviously is a good thing (compared to gaining fat, only), you should be aware that "gains" like that won't be particularly aesthetic. After all, even the subjects in the high protein group gained more fat than muscle and though the difference was statistically insignificant, the mere fact that you have more muscle than fat tissue should tell you that your body fat percentage increases even if you gain identical amounts of fat and muscle weight. So, I guess that the average participant of the Bray study was probably not very pleased with the way he looked when the study was over.

Figure 1: Composition of the diet of the participants at baseline and during the 8 week intervention period (left); lean body mass and fat mass (in kg) of the participants before and after the intervention (right; data calculated based on Bray. 2011)

So, if a simple increase in the protein to fat + carbohydrate ratio won't suffice to make sure that the weight you are gaining on your hyper-caloric diet, is not fat weight, what else may help? Well, the results from another recently published study by Christoffer Clemmensen et al. may provide at least a hint to another adjustment that to our dietary regimens that could make a difference, a modifications at the micro- not the macronutrient level...

An arginine rich low protein diet builds muscle, and melts away body fat

Allegedly, this is only another rodent study, but hey, haven't we been able to predict the outcome of the Bray study based on previous data from rodent studies, as well? Yes, we have! So, bear with me, because the effects the 10% total protein, of which ~8% came from casein and 1.8% from supplemental l-arginine (cf. figure 2) had on the body composition of the 6 week-old mice in the Clemmenson study, were pretty astonishing (Clemmenson. 2011).

Figure 2: Macro- and micronutrient (protein component) composition of the diet the control and arginine groups of the Clemmenson study were fed in the course of the 10-week intervention period (Clemmenson. 2011)

Contrary to previous studies, where the effects of l-arginine have mostly been tested in rodent models of diabetes or other (human) metabolic diseases, the mice in the Clemmenson study were perfectly healthy. After a 2-week acclimatization period at the lab, they were simply put on one of the two low-protein (8% basal + different amino acid mixes, cf. figure 2) diets and judged by their weight development over the 10-week study period (cf. figure 3, right) the effects appear to be negligible.

Figure 3: Additional cumulative energy intake over 21day and 72h period, as well as reduction in feed efficiency in l-arginine fed mice over 21day period (left); total body weight over the course of the whole study (right; data based on Clemmenson. 2011)

Things are becoming increasingly interesting, though, when we also take into account that the mice on the arginine diet consumed more food, so that their "feed efficiency" that it the amount of weight they were gaining per gram of food they were consuming was profoundly reduced (-48%, cf. figure 3, left). What is yet more important than a reduced "food efficiency", which by the way is the fundamental working principle of stupid "weight loss pills", such as the "fat blocker", Alli, was that the low-protein, "high" arginine diet did in fact have the effect that was falsely ascribed to the "high protein" (who says 25% is high?) diet in the Bray study. It lead to a greater increase in muscle over fat mass compared to the "normal" diet, despite a ~15% increase in total calorie intake (cf. figure 4)

Figure 1: Body composition and fat weight of mice after 10 weeks on normal and high l-arginine diet low-protein diet (data based on Clemmenson. 2011)

Although this effect could partly be explained by an increase in energy expenditure in the absence of statistically significant changes in total activity levels, the absence of measurable increases in UCP1 and UCP2 (uncoupling proteins the activity of which will make a metabolism "waste" more energy in form of heat) suggests that another, more significant effect of the low-protein, "high" l-arginine diet may be the driving force behind these beneficial changes in body composition.

Micronutrient (l-arginine) mediated modulation of insulin sensitivity as a key to lean gains

Figure 5: As the correlation between fat mass and basal insulin levels shows, getting fat has little to do with the amount of insulin in your blood, but everything with the way your body reacts to a given amount of insulin. That the latter is not determined by total protein intake, but by refinements in the micronutrient composition, should make you reconsider if "how much protein should I eat?" really is the most important question to ask.

As it turns out, this driving force is in fact an old acquaintance: insulin! Or rather the arginine-mediated increase in insulin sensitivity about which the scientists write:

OGTT and ITT, performed at week 8 and 9, respectively, demonstrated that L -Arg supplemented mice were signifi-cantly more glucose tolerant (34% reduction in AUC, P < 0.03) and insulin sensitive than mice on the control diet. Fasting blood glucose levels were significantly lower in the L -Arg supplemented group (7.9 ± 0.4 mmol/L) compared with the control group (9.7 ± 0.2 mmol/L, P = 0.003), but basal plasma insulin concentrations after 10 weeks on the diet did not significantly differ between the two groups

Now, don't get me wrong (I know you will ;-), I am not saying that eating a low-protein diet with "huge" amounts of l-arginine in it (the human equivalent, by the way, would have been ~0-8g/kg body weight) is going to turn you into a ridiculously ripped mass monster. I am just trying to make a point that we are only scratching the surface, when we focus solely on the "good protein", the "bad carbohydrates" or the "good and bad fats"... and that the body fat of the mice in the Clemmenson correlated with total insulin only in the "control", yet not in the l-arginine group (cf. figure 5), goes to show that even the contemporary vilification of insulin will probably have to be re-evaluated in light of the effects the identical levels of insulin can have on the body composition and other important health factors in different dietary contexts, individuals and probably even time-points.

Note: As soon as I find the time I am going to write something more comprehensive on the whole "how much protein is enough and when can it even become detrimental"-issue... promise ;-)

So, before you jump aboard the boat of any "unlimited whatever" nutritional strategies, you better focus on the myriad of small adjusting screws, which will all have to be in place to optimize firstly your health and if that is in place, secondary your performance or body aesthetics.... and I guess, I don't have to remind you that the SuppVersity is the place to go for your daily dose of information that will help you not to "screw up" ;-)

Adelfo Cerame - Road to The Wheelchair Nationals '12: Proper Nutrient Timing is Probably the #1 Key to Lose Fat and Still Build Muscle While Being in a Caloric Deficit

Image 1: Progress and success can be mean bitches. Not only are you raising the bar constantly, a physical transformation like the one Adelfo is going through right now, will also require a constant revision of your dietary and training regimen... and, sometimes, this change may mean that you just keep rolling, instead of making a previously planned change - as awful as that may sound for the average OCD bodybuilder  ;-)

I don't know about you, but I fell that, sometimes, it is much easier to identify mistakes and pitfalls in other people's dietary and training regimen than it is in your own. It is a very peculiar form of tunnel vision, or I should say, blindness that befalls us, whenever we are working toward a certain goal for weeks and months. When we have laid out our plan of attack and have celebrated our first victories. In these situations, where we tend to believe that everything is working out "as planned", the very plan we thought be "optimal" at time point T1 may now, at T2, when, with the progress we have made, the foundations on which we have based our plan have changed, strategies we previously considered "optimal" could actually hamper our progress. In situations like these, mentors and real friends who do not shy away from arguing with you are of paramount importance, they will help you in re-assessing where you stand, how you got there and, most importantly, how to proceed. Sometimes, however, all it really takes is an innocent question, a question that will make you pause to think, a question like the one of which Adelfo Cerame is now going to tell you...

"How have you grown on a caloric deficit?! Your arms look bigger too!"

This was one of the messages I got on my phone, from one of my old mentors (when I first started getting into bodybuilding). He had seen some of my progress pics on line and obviously must have liked what he saw. When I called him back, I told him that I could not really explain the underlying biophysical mechanism, but knew that it must have been a direct consequence of the combination of intermittent fasting and the new training techniques (EDT, static holds, 5x5…; lifting heavy, low volume…), I have incorporated into my routine over these first 12 weeks of my contest prep.

Image 2: While it may be debatable whether Adelfo actually gained, significant amounts of muscle mass, the "muscle quality" certainly did not suffer from not eating 6 meals a day ;-)

About a day later, when I discussed the topic with Dr. Andro, who did not seem to be very surprised about the astonishment of my former mentor, we agreed that the caloric content, the overall macronutrient composition of the diet and the food quality, aside, the way I was timing my meals within my feeding window, could be a, if not the decisive factor which allowed me to maintain or even put on a little bit of extra muscle, as Dr. Andro put it "against the misunderstood laws of thermodyndamics" - or, as a normal human being would probably say it: Although I was actually eating less food than I needed.

The real key, this at least what I believe, to "growing on a caloric deficit" is the timing and macronutrient composition of the meal(s) immediately post workout. Ever since I began intermittent fasting, the meals right after my workouts were the biggest, or I should say, most nutrient dense ones: I am getting about 75-80% of my daily caloric intake is during my post-workout meal - and that does not include the 25g of whey protein I down immediately after my workouts.

When lean is not ripped enough, calories begin to count again

Image 3: Branch Warren is one of those guys where ripped is not shredded enough. We will see if he can make a comeback from his quadriceps injury in 2012 (img musculardevelopment.com)

A pros pos calories, for someone in my position whose body fat percentage is already below the 10% mark and for whom being ripped, is only the prestage of being totally shredded, calorie counting, or I should say, a high degree of awareness of the amount of nutrients I am eating becomes is a must. Over the last two months I have continously been cutting back on my daily energy intake: 1600 kcal on December, and now 1400 kcal.

Interestingly, the reduction in calories has not hampered my strength, my energy levels or overall well-being, yet. I did not feel sleepy, lethargic, or irritability. My sex drive did not drop and the extreme cravings and the never-ending battle with hunger, I am used to from previous preps, did not occur.. much of this is probably related to the fact that even on 1,400kcal /day I can still eat to satiety within my feeding window. I am nevertheless suspicious, especially because this is the first contest prep, where I am using and intermittent fasting protocol and who knows, maybe the hunger pangs will come...

No hunger, no lethargy, no cravings, but still: Better save than sorry ;-)

The call I received from my former mentor, on the other hand, reminded me that my progress on the "high" 1,600kcal regimen has actually been quite amazing, so that I decided that, even in the absence of hunger pangs, cravings and lethargy, it would probably be wise to smoothly increase my caloric intake again, in order to have more "caloric reserves" (not in terms of body fat, but in terms of being able to cut back on caloric intake without the risk of losing too much muscle mass), when, later in my prep, my progress begins to stall.

Image 4: If you want to know more about the working principles of intermittent fasting and why eating more frequently does not automatically translate into better weight loss read the Intermittent Thoughts on Intermittent Fasting.

As I have mentioned before, the timing of the meals, i.e. the characteristic fasting-feeding interval and the nutrient density and macronutrient composition of the individual points, are the constituent factors of my success. I mean, if you were simply dividing those 1,600kcal by 6 and eating your "healthy and weight loss promoting" (watch out for the irony, here!) 6 bodybuilder-standard-contest-prep-meals a day that would be only 266kcal per meal... what? Yeah! That sucks! And to be honest, I don't even want to do the math for the 1,400kcal I have been eating the past weeks. Now, if you allocate the same meager 1,600kcal to 3 meals, eating 20% (320 kcal) of your daily allowance pre-workout, 60% (960 kcal) post-workout and 20% (320 kcal) with your last meal - all within a 6-8h time frame - that does not only sound much more satiating, it also is ;-)

An exemplary nutrition plan on a 1,600kcal intermittent fast could look like this:

• pre-workout: 50g protein/ 1 cup coconut milk/ 1 tbs. of coconut oil = 400 kcal
   
• post-workout meal: 100g protein/ and as much veggies as you want, and you can even throw in a 12 oz potato if you want! And you’d still be at 640 kcal with 320 more to go!
   
• last meal before the fast: Protein shake (25g protein/ 1 raw egg/ 1 cup of coconut milk) = 210 kcal

Obviously the numbers aren't 100% accurate, but that this does not matter as long as you are not tricking yourself by adding 50kcal in here, and another 50kcal there, it won't make a difference if your pre-workout meal is 400kcal or 320kcal...the take home message here is that by timing your foods appropriately and exploiting the beauty of intermittent fasting you can still eat to satiety while dieting really hard... and I guess the images I posted last week should proof that not feeling hungry won't hamper your progress, at all. In fact, and this is maybe one of the most important lessons I have learned during the past weeks, the exact opposite is true.

Increasing caloric intake on a diet, but how?

Image 5: Grumpy regular or lovely sweet potato, which one is better? Which will make you fat? Or is it possible that there actually is no difference? Learn more in the Potato Manifesto Part 1 & Part 2

As I mentioned earlier, the success I have had, made me reconsider my earlier plans as far as the overall calorie intake is concerned. Now, while it is one thing not to cut back on calories, it is another to re-introduce them, when the goal is fat loss, not mass gain. In view of the fact that the 1,400kcal would at best make me peak too early, in the worst case leave me flat and catabolic, when I am rolling onto the stage in 11 weeks, it would be whacky not to take the "risk"... especially because the reinstallment of some starchy post-workout carbs to get back into the ~1,600kcal/day zone, coincides with my return to escalating density training. During those high-intensity EDT workouts, I am certainly going to benefit from some readily available glucose to replenish the glyocgen stores of my muscles. I will still make sure to keep my starchy carb and fruit intake <100 and will time them so that they will fall right into the 2h window after my workouts, so that the end result (post workout) is probably going to look somewhat like this...

• 50g of lean meat as the main nutritional protein source, plus ...
   
• 6-8 oz white potato (30-40g carbohydrates) for the starchy carbs, plus ...
   
• the rest of my 50g of carbohydrates from veggies & fruit, of which I don't really count the veggies, I just load up on them, plus ...
   
• no more than 10g of fat mostly from the meat
   

A usual, I'll stick to this for now and monitor my physique week to week, in order to make adjustments whenever I feel they become necessary.

"Get as lean as you can with as much carbs as you can"

At first I was a little hesitant to add carbs back in. I did not want that water retention (cf. "Three Basic Tweaks to Get Rid of Excess Water") in my lower abs to reappear, but at the same time, I don’t want to be running too flat for 11 weeks. Plus, adding some starchy carbs back into my diet post-workout meal might even help with putting on some more strength and, concomitantly, lean mass while still cutting down.The whole situation reminds me of something I heard a while back from one of the "diet gurus", who may not get everything right, but whose success with clients is something you can hardly deny: "You want to get as lean as you can with as much carbs as you can get away with" ... well, something along the line ;-) The main massage, was though that you should try and keep your muscle as "full" as possible without compromising your fat loss... and while I was still musing about staying full while losing fat, I realized that within the past weeks, where I still had my post-workout share of carbs, exactly that had worked out pretty well.

Recipe of the week: Almond Butter Chocolate Blueberry Low-Carb Flap Jack

Whenever I'm craving a high glycemic index,, processed, pro-inflammatory pancake, but I canÄt have one, I improvise with these...

Ingredients:

• 8 egg whites (you can also use all whites)
• 1 whole egg
• a couple poofs of cinnamon powder
• 1 tsp. vanilla extract
• 1-2 packets of truvia (stevia)

Blend ingredients in blender till’ it starts to fluff and pour in a hot pan with a little bit of coconut oil.

Tip: Just add 2 tbs. of almond butter, ½ cup of blueberries and waldens calorie-free chocolate syrup. And here’s your finished product!

The flipside to this insight is yet that I will have to lie aside my "water retention phobia"... I thusly keep telling myself that when I am taking in my carbs within the 2-hour post-workout window, where, as Dr. Andro pointed out in one of our nightly discussions on facebook, the "exercise-dependent increase in GLUT-4 receptor expression on your muscle will make them suck up the glucose without the need for large amounts of insulin that would be necessary at other time points, i.e. in a non-exercised state, to initially trigger the GLUT-4 expression", the glucose from the potatoes and fruit is not only most likely go into my muscle glycogen stores, but this is also going to happen in the presence of a minimal (compared to other time-points) amounts of insulin. Moreover, he reminded me - as long as my overall physique keeps improving - I will still have more than enough time to get rid of any excess water within the last 4 weeks of my prep...

So, I guess I will just have to deal with the little inevitable bloat that comes with each and every gram of carbohydrate for a few more weeks... and who knows, maybe the water is not even coming back again? If you are interested in that and whether my assumption that I could still make progress on the 1,600kcal regimen will turn out to be correct, you will have to come back next Thursday to read the the latest installment of my weekly contest prep blog right here, at the SuppVersity.

Selenium, the Fertility Mineral!? Organic and Inorganic Selenium Ameliorate Reductions in Testosterone, Testicular Damage and Abnormalities in Sperm Quality in Obese Mice

Image 1: With enough selenium in vivo, "in vitro" (-fertilization) may not be necessary.

If you have not heard about it in one of my previous blogposts, you may probably heard about the antioxidant, pro-fertility effects of selenium in the context of Tim Ferris' "selenium experiment" in the 4-Hour-Body. Ferris claimed that by just eating a handful of Brazil nuts (544µg selenium per ounce) every day shot his testosterone levels and libido through the roof. Now, what most people probably overheard, though, was that Ferris was selenium deficient to begin with. Just as every bodybuilder's holy grail, zinc, selenium won't help up your testosterone or fertility if you have already plenty of the potentially toxic trace mineral in your diet. In view of its central role in the antioxidant defense system of our bodies, it is however likely that selenium requirements increase, whenever our bodies are exposed to increasing amounts of oxidative stress.

When your body fat sets your testicles on fire, selenium may come to a rescue...

One of the most common causes of increased oxidative stress, these days, are the increased levels in highly oxidizable very-low density cholesterol and triglyceride levels which appear to be an almost inevitable consequence of the "modern" lifestyle (=sitting on the couch and washing down your fast-food, as well as your low-fat "healthy" cereals, pasta and rice with soda). A recent study from scientists from the Institute of Nutritional and Metabolic Disorders of Domestic in China does now show that an adequate amount of dietary or supplemental selenium, which is, as you may gather from the data in table 1, pretty scarce in everything that was not grown or raised on selenium-rich soil, may not be able to reverse all negative side-effects, but could ameliorate them so that reproduction would still be possible (Ibrahim. 2011).

Table 1: Selenium content of common foods (based on data from the NIS. 2011)

While the basal diet, which had been enriched with cholesterol, lard and cholic acid, so that it would mimic the obesogenic high carb + high fat diet, researchers love to mislabel HFD (high fat diet), contained only 0.04 µg/g of selenium (without the addition the lard, i.e. for the control group, the se-content was 0.05µg/g), both the inorganic selenium HF-diet and the diet of the animals that received a combination of (organic) selenium (75% selenium-methionine) and probiotics (C. utilis and S. thermophilus strains) contained ~6x the amount of selenium (0.3µg/g chow). For humans this would translate to ~1.2µg/kg and 7µg/kg, respectively (since the scientists did not report food intake and body weight of the animals, I based this calculation on the respective data from other HFD feeding studies with mice).

Amelioration? Yes! Reversal / complete prevention? No!

After 75 days on control, high fat, high fat + probiotic only, high fat + inorganic selenium only, and high fat + 90% organic selenium + probiotic diets, the testis of the mice showed histopathological changes even a non-expert as I am one would identify as "probably not healthy" (cf. illustration 1):

Illustration 1: Compilation of the histopathological examination of murine testes (H & E, ×400; based on Ibrahim. 2011)

The evident degenerations, decreases in cell population, and irregularities went hand in hand with a pretty profound changes in the quality of sperm (cf. figure 1), which were ameliorated, yet not prevented in the selenium and selenium + probiotic groups.

Figure 1: Measures of sperm quality - sperm count and motility (left); relative incidence of sperm with abnormal heads and tails (right; data based on Ibrahim. 2011)

In that, it is noteworthy that the selenium + probiotic (SePro) group had an only 1.5x increased amount of sperm with abnormal tails. The latter can thusly hardly be the reason for the -20% reduction in overall sperm motility.

Figure 2: Lipid (left axes) and testosterone (right axes) levels in the different groups (left); HDL to total cholesterol ratio and change in testosterone levels compared to control (right; data calculated based on Ibrahim. 2011)

In view of the fact that the male gonads do not only produce sperm, but also testosterone, it is not surprising that selenium and selenium + probiotic supplementation had a similar ameliorative effect on the diet induced reduction -47% reduction in testosterone (cf. figure 2). The +3% increase in serum testosterone (over the obesogenic diet group) in the probiotic only group, on the other hand, lacked statistical significance.

Image 2: The importance of selenium for thyroid function, specifically the local conversion of the "inactive" T4 to the "active" T3 is not the only reason why women should try to achieve adequate selenium intakes, as well.

Selenium for women? While it appears that research has hitherto focused on the role selenium plays in male health, there is a handful of studies which suggest that adequate levels are just as important for women, as they are for men. The results of a Polish study from 2006, for example, stand in line with the, as of late, controversial anti-carcinogenic effect selenium is supposed to have on prostate cancer. According to the authors, the provision of selenium supplements to women with a genetic disposition for breast and ovarian cancer led to a small, but statistical significant reduction in cancer rates (Huzarski. 2006). In 2009, Hermsdorff et al. observed a statistical significant inverse correlation between selenium intake and serum levels of retinol-binding-protein 4, a marker of whole body inflammation and purported contributer to insulin resistance and diabetes (Yang. 2005), in 74 young (~20y) healthy women (Hermsdorff. 2009). In post-menopausal women, Llaneza et al. found a non-negligible association of low-serum selenium levels and higher LDLc and triglyceride levels (Llaneza. 2009). A 2007 study by Negro et al. underlines the particular importance of adequate selenium levels for thyroid health during and immediately after pregnancy (Negro. 2007). And according to a recent review of the role of selenium in reproductive health, low selenium levels in the follicular fluid are a characteristic feature of "unexplained infertility" in women.

As far as the "potency" of the probiotics is concerned, the study was thusly quite disappointing. That the scientists who were proud to have developed a "Se-enriched probiotic as a new feed additive product for promoting animal industries" do not explicitly state that, is understandable, but won't stop me to repeat my previous recommendation to just add a handful of brazil nuts to your diet on a regular basis to make sure you satisfy your selenium requirements.

Selenium intoxication from Brazil nuts? I don't think so...

Image 3: Eating lots of brazil nuts and other selenium rich foods until they achieve what the US consider "toxic" serum and plasma levels does not seem to impair the health of the inhabitants of the regions around the Tapajós River in Brazil - on the contrary, their cardiovascular health is outstanding (Lemire. 2011)

That this practice is not going to result in selenium toxicity has, by the way, been shown only very recently in one of those studies that analyze traditional diets, which have become so in-vogue, as of late. Lemire et al., who analyzed blood (B-Se) and plasma (P-Se) samples from members of the communities which live along the Tapajós River in Brazil, did not only find that these people had selenium levels well beyond what is "considered toxic" in the US, they also state that their results "support the need to re-assess Se toxicity considering factors such as the chemical form of Se exposure, route of exposure (inhaled versus ingested), co-exposures to toxic elements such as mercury" and hint at "a possible association between high Se status and cardiometabolic health in this study population." (Lemire. 2011) So, men or woman, fertile or infertile, fat or lean... you better make sure you get your share of brazil nuts, today ;-)

Sugar Addicted or Just Stressed Out? Study Investigates Modulatory Effects of Different Macronutrient Compositions on Serotonin in the Presence and Absence of Stress

Image 1: She has the reason she is so relaxed right in her hand... but does she know that sugar is no sustainable way of coping with stress unless you don't care that you thusly pave the way from from initial episodes of hypoglycemia over binges, to obesity and diabetes.

"Sugar addiction" is a recurring theme in the blogosphere and whether it exists or not and what potential causes and treatments might be is still a matter of a partly very emotional debate. If we go by the definition of "addiction", of which the venerable Oxford English Dictionary says that it was "a condition characterized by regular or poorly controlled use of a psychoactive substance despite adverse physical, psychological, or social consequences, often with the development of physiological tolerance and withdrawal symptoms", it would be, if we had prove that sugar is a "psychoactive" substance. After all, the "adverse physical, psychological, or social consequences", i.e. diabetes, obesity, eating disorders, isolation, depression etc., are too obvious to be argued away - and I don't have to tell you about the "withdrawal symptoms", do I? Or, could it be that this is all just in our brains? Well, according to a recently published study from the Neurochemistry and Biochemical Neuropharmacology Research Unit at the Department of Biochemistry of the University of Karachi in Pakistan (Moin. 2011), it actually is ;-)

A amino acidic tale of sugary binge eating and fat anorexia

In their study, which was unfortunately conducted on rodents, not humans (apparently decapitation of human subjects for research purposes is prohibited in Pakistan ;-), Samia Moin and his (or her?) colleagues tried to assess how different dietary macronutrient compositions effect the ability to cope with and the brain response to stress. To this ends the scientists fed 48 rodents with diets that contained either 1/3 sugar (sugar diet), 1/3 beef protein (protein diet) or 1/3 fat (fat diet) in addition to the standard rodent chow (normal diet). Unfortunately, they did not provide the specific macronutrient composition of the diets, so that I had to calculate the latter on my own. The results are depicted in figure 1 and are based on the assumption that the Pakistani "standard rodent chow" is identical to the one animals in US labs are fed ;-)

Figure 1: My calculation of the macronutrient composition of the experimental diets; the calculation is based on the "standard rodent diet" that is used in US labs, whether that was identical to the one the Pakistanis used, I cannot tell.

If you take a look at the macronutrient composition of the different diets, the inter-diet difference between the "normal" and the "sugar diet" ended up to be not so significant. I mean 58% vs. 72% of the calories from carbs? For me both would be high carb and thusly it should not really surprise you that of those 24 rats who had to endure 2h of immobilization stress the rats in the "normal" and "sugar" group showed a similar, yet for the "normal" diet 1-day postponed, stress response: They ate more!

Figure 2: Effect of repeated stress (2h immobilization) on food intake in the different groups (data calculated based on Moin. 2011)

If you look at the data in figure 2, it does yet become obvious that - at least within the study period - "more" has to be understood relative to an initial stress-induced decrease in food intake, which, and this is another interesting finding, was sustained at -44% (average over the 5-day period) in both the high fat and the high protein group.

The Pakistani perspective: "Carbohydrate help you cope with stress!"

From the perspective of the Pakistani scientists, this "restorative effect" of a high carbohydrate diet on stress-induced appetite may be a good thing, from the perspective of someone living in a society with an overabundance of both food and stress, it must however be consider a potential risk factor for obesity.

Figure 3: Changes in serotonin (5-HT), its metabolite 5-HIAA and its precursors in response to dietary intervention; the "normal" diet serves as a reference (data calculated based on Moin. 2011)

If we take a closer look at the diet induced changes in brain 5-HT (=serotonin), 5-HIAA (=main serotonin metabolite) and brain and serum tryptophan (=serotonin precursor) levels in figure 3, it becomes quite obvious that the changes in the macronutrient composition alone already "mess" with the serotonin metabolism. What stands out, here is that, contrary to the "sugar" and the "protein diet", the "fat diet" increases the amount of serotonin in the brains of the unstressed rats compared to the "normal" control by +20%.

Figure 4: Changes in serotonin (5-HT), its metabolite 5-HIAA and its precursors in response to stress in the different diet groups; data expressed relative to unstressed controls; only changes marked with an asterisk (*) are statistically significant, p < 0.05 (data calculated based on Moin. 2011)

A different picture emerges, though, when we take a look at the effects of combined macronutrient modulation and stress (cf. figure 4). Contrary to the changes in the "normal" and "sugar group" which (plasma tryptophan levels aside) lack statistical significance, we see a reduction serotonin metabolism (as indicated by reduced 5-HIAA levels) in both the "protein" and the "fat" diet and the serotonin level in the "protein" group was profoundly elevated in response to the 2h immobilization stress.

What implications do these 5HTs, 5-HIAAs and ABCDEFGs have?

From previous studies, we know for quite some time that high protein diets are associated with higher rates in stress-induced depression (Markus. 1998). Moreover a reduced 5-HIAA / 5-HT ratio in the brain has been identified as a characteristic feature of depression (Zangen. 1997). If we keep that in mind and take a final look at the data in figure 4 and figure 5, we would have to draw the following conclusions:

• a high sugar diet modulates the 5-HIAA / 5-HT in an "anti-depressive" way
   
• a high protein diet does not change the 5-HIAA / 5-HT ratio as long as there are no external stressors, when stress comes into play it is associated with a profound "pro-depressive" decrease in the 5-HIAA / 5-HT ratio
   
• a high fat diet induces a pro-depressive reduction in the 5-HIAA / 5-HT ratio in the absence of stress, but is associated with a less pronounced reduction in the 5-HIAA / 5-HT ratio in response to stress, when compared to a high protein diet

Now its up to you to tell me whether these neurotransmitter changes in a rodent study and the associated pro- and anti-depressive effects reflect the way you feel on different diets in the presence and absence of stress... and I suggest, whenever you feel good with the way you eat, discard all the information I have just given you and keep doing what works for you. Not just because you are no rat, but simply because we are all wired differently and this wiring may change overtime :-)

Intermittent Thoughts on Building Muscle: Quantifying "The Big T" - Do Testosterone Increases Within the Physiological Range Really Matter? And How Much is too Much?

Image 1: As it turns out, changes within the broad physiological range, have only negligible effects on muscle mass. Their potential negative impact on body fat is yet startlingly pronounced (see also fig. 2)

Welcome back! I am not going back on yesterday's promise and won't let "the Big T" slip out of chokehold of science ;-) So, where was I? Ah, yes... we have seen that out of the >11,000 published studies where the authors used the words "testosterone administration" (numbers according to Google Scholar), there appears to be exactly one (this is "1" as in only one ;-), in which the researchers dared to "proof" that testosterone alone, i.e. in the absence of exercise or dietary interventions, "builds muscle" - and that in otherwise completely healthy young men. We have also seen that there is a clear cut dose-response relationship with the largest increases in lean muscle mass and the most profound decreases in body fat in the high dose (600mg test enanthate) group.

More is more, but is more better?

If you took a scrutinizing look at figure 1 from yesterday's installment, you probably will have noticed that quadrupling the amount of testosterone enanthate from 125mg /week to 600mg /week did not quadruple the the amount of lean muscle the subjects gained - or, as an economist would immediately realize, the marginal utility is diminishing!

Figure 1: Dose response relationship of muscle gain (in kg) per mg of testosterone enanthate; the white line indicates a dose that would probably have produce testosterone levels identical to baseline (calculated based on Bhasin. 2001)

To make that a little more comprehensible, I have plotted the respective ratio of the amount of free mass the subjects gained to the amount of testosterone enanthate that was necessary to induce this changes in figure 1. In view of the fact that the different ways of administration / natural ways to boost testosterone will all have different effects on the actual levels of serum testosterone, I will however leave the interpretation of this muscle gains / test-enanthate ratio to those of you, who have a vested interest in this topic ;-) I, for my part, will focus on the changes in total testosterone (which correlated almost perfectly - r = 0.996, as of my own calculation - with the free testosterone levels in this study) and the associated increases in lean muscle mass. In that, it should be noted that the testosterone levels were measured at the end of each week meaning that right after the injection of the given dose of testosterone enanthate, which has a half-life of 4-5 days, the levels will have been markedly higher.

Surprise, surprise! Slightly below the "natural range" you get the most bang for your... T!

If we take into consideration that the "normal range" for testosterone levels ranges from 300 to 1000 ng/dl and that the subjects in the Bhasin study had baseline levels of ~600 ng/dl, all changes between -50% and +66% would be within what the medical orthodoxy considers "normal" (note: if the subjects already had "low" levels, even changes of +200% would still be within the normal range, please keep that in mind, when you read about the latest and greatest test-boosters ;-):

Figure 2: Relative change in lean and fat mass in response to changes in serum testosterone levels; the green area indicates "normal" = physiological testosterone levels; the asterisks (*) denote statistically significant (p < 0.05) changes vs. baseline (calculated based on Bhasin. 2001)

If we look at the data and acknowledge that only those data points I tagged with an asterisk (*) represent statistically significant changes from baseline (p < 0.05), it is quite obvious that elevations and even reductions of testosterone levels within the normal physiological range do not have any significant effects on skeletal muscle mass. As far as "building muscle" in the absence of exercise and nutritional interventions is concerned, the magic does not begin before we reach super-physiological concentrations of testosterone.

A brief note on the effect size: If you look at figure 2 without using your brain, it may seem that by just using enough test you would in no time become Mr. O. If, however, you take a closer look at the slope within the supraphysiological range, the latter signifies that for each +1% in lean mass you would have to increase your testosterone level by >27% - and maintain that over a time-course of 20 weeks! And as if that was not enough, even if you would survive boosting your levels into the >+400% zone, you should be aware that the slope will level out and you will probably need another +100% to make the +1% addition in lean mass. If, on the other hand you are not using injectable, but a natty test booster, or test or measure your levels right after or shortly after injections, chances are that you would have to have +60-80% increases in serum testosterone for 1% increases in total lean mass and that within 20 weeks! After all, 7 days after the injection (which is when the testosterone levels of the subjects were measured) the serum levels should actually be <50% of what we see in the hours immediately after the testosterone enanthate injection, which has, as I have already mentioned, a half-life of about 4-5 days.

What is almost frightening, though, is the tremendous (and statistically highly significant) detrimental effect reductions of testosterone within the "normal range had on the fat mass of the subjects (-47% testosterone = +17% fat mass; -57% testosterone = +36% fat mass). These obesogenic effects of low testosterone levels may be related to the direct anti-adipogenic effect of testosterone (Singh. 2006) and fits perfectly into the emerging (yet still not canonical) image of low testosterone levels as result of and contributing factors to the obesity epidemic (Corona. 2011).

An analysis of the complex interrelations between your beer belly and that which is hidden from your view beneath the former would yet go way beyond the scope of this installment of the Intermittent Thoughts, where testosterone's effects on skeletal muscle, not adipose tissue, are at the center of our attention. And that these effects should obviously not be restricted to increases in "lean mass", but should also be measurable in terms of "size", i.e. muscle circumference / cross-sectional area (CSA), and strength gains, is self-evident.

Does testosterone make you bigger, leaner and stronger?

As those of you who are familiar with the results of any of the 11,000-1 studies on hypogonodal, old or sick patients, where HRT-induced increases in total skeletal muscle mass are oftentimes similarly "statistically insignificant", will probably have expected the researchers would nevertheless not actually have needed an expensive DEXA scanner to see that the muscle mass of their subjects had increased - as the data in figure 3 shows, a simple measuring tape would have been sufficient:

Figure 3: Relative changes in thigh and quadriceps circumference and maximal leg press strength and power (measured on a Nottingham leg extensor power rig) in response to 20 weeks on different dosages of testosterone enanthate (calculated based on Bhasin. 2001)

For the muscle volume, just as for the the previously discussed changes in total muscle mass, the marginal utility is again maximal within the upper "physiological range", which corresponds to the use of 125mg of testosterone enanthate per week (figure 3, green).

For both the leg press strength, as well as the total leg power, though, a different picture emerges: Contrary to the weight and size gains, the gains in strength and power in the 125mg were not statistically significant (p = 0.42 and p = 0.59). Moreover, the aforementioned effect of "diminishing returns" with doses of testosterone >300mg /week is way more pronounced for leg strength and power than it is for the gains in total muscle mass and leg muscle volume. And as if that was not already confusing enough, in contrast to the +7% increase in the 125mg group, the + 6% increase in leg press power in the "low testosterone" group (50 mg) did reach statistical significance (p = 0.02).

Testosterone, myostatin and IGF-1 - tying the knots together

In order to explain this "strength anomaly", we will have to resort to what we have learned in previous installments of this series about the differential effects of myostatin and IGF-1 on muscle size and composition. Assuming that you have read all the installments of the Intermittent Thoughts, you will be familar with the results from the Quaisar study, I discussed in "What is Hypertrophy". You will also remember that Quaisar et al.'s observations showed quite clearly that the "uncontrolled" muscular hypertrophy in the myostatin negative mice left them with huge, yet dysfunctional muscles. The over-expression of IGF-1 on the other hand, facilitated a profound restructuring process within the skeletal muscle in the course of which the recruitement of satellite cells and the subsequent addition of myonuclei allowed for "healthy" growth that would not burst the maximally allowed myonuclear domain sizes (cf. "Getting Big Means Growing Beyond Temporary Physiological Limits").

Figure 4: Correlation (R²) of muscle volume and performance with testosterone and IGF 1 (left); testosterone / IGF-1 ratio before and after 20 weeks on different amounts of testosterone enanthate (right; data calculated based on Bhasin. 2001)

Against that background the testosterone to IGF-1 ratios on the right hand side of figure 2 in yesterday's installment of the Intermittent Thoughts (the graph on the right hand side of figure 4 is an identical copy in figure 4) should get a whole new meaning: If IGF-1 is required to keep rapidly growing muscles functional, the reason for the stalled power and reduced strength gains in the 600 mg testosterone enanthate group could well be a relative lack of IGF-1 (>3.5x elevated testosterone / IGF-1 ratio). The superior correlation (R²) between performance measures and IGF-1 values of the study participants (cf. figure 4, left) would does not only support this hypothesis it also underlines the vital importance adequate insulin-like growth factor levels (and its splice variants, which have unfortunately not been measured in this study) may have for "chemical athletes", in particular.

How all this is (or at least researchers believe it is) eventually in fact related to myostatin, how testosterone affects the fast- to slow-twitch fiber ratio (which could explain the anomalous increase in leg strength in the 50mg test E group), mitochondrial biogenesis and satellite cell function, are yet topics that will have to wait until Sunday, when - just as every week - I will sacrifice my free time and write down more Intermittent Thoughts Building Muscle.

Intermittent Thoughts on Building Muscle: Zoning in on "The Big T" - Does Testosterone (Alone) Build Muscle?

Image 1: As a "serious" researcher you better don't use the words "testosterone" and "muscle" without "anti-doping", "hypogonadism" or "sarcopania" in one of your papers, if you don't want to risk your career.

In many of the past installments we have been talking about funky things such as mTOR, myostatin, IGF splice variants and even more exotic stuff. Testosterone, the "big T", the allegedly most important contributor to skeletal muscle hypertrophy has hitherto been "overlooked" - was it the principle of saving the best for last which drove my decision not to address the influence of testosterone on muscle building in the first installment? Was it ignorance? Plain stupidity? Or did I want to start the new Year off with a big Tang... ah pardon "bang"?  The answer is, I was scared. Not because the word "testosterone" has gotten such a bad rep in our metrosexual/feminist society that I was put on the index of "too masculinizing" websites, but rather because I feel very uncomfortable, whenever I have to talk about things I don't fully understand... and if we are honest to ourselves, few other aspects of the physiological underpinnings of skeletal muscle hypertrophy are still so obscure as the role the "big T" plays in-between all those signaling cascades, phosphorylated proteins and newly discovered growth factors.

Testosterone, the big bad T!?

One reason for the our lack of knowledge about how (some researchers may even say "if") testosterone builds muscle certainly is a practical one. Unless you can do your research under the pretext of trying to

• treat muscle wasting disorders (associated with age, cancer, AIDS, etc.),
• invent new methods that could be useful in the WADA's antic battle against doping, or
• help infertile or hypogonodal men to a better life

you, as a researcher, will not only have a hard time to find "sponsors" to fund your obviously very expensive (think of large scale studies with many healthy human participants, think of "potential risks", think of compensations, think of all the expensive lab work) studies, you may even risk to get labeled as "the doping doctor", an appellation which would certainly not be career-enhancing.

Testosterone, the Jerry Bruckheimer of skeletal muscle hypertrophy?

Even if you got enough funds for your research, were not afraid to put your reputation at stake and got the approval of all the ethical committees, you would still be faced with the problem that testosterone, contrary to muscle protein synthesis, mTOR activity in tissue samples, and even the muscle specific splice variants of IGF-1, is a systemic hormone. It is (at least this is what scientists currently believe) not expressed at the tissue level (autocrine), but produced (predominantly) in your testes, from which it then carried through your bloodstream to "dock" (even that is a total inadequate oversimplification) to its receptor and... but I don't want to waste our time by going into the details of a process, of which I would assume that you have read about roughly 143x on other websites. Instead, I want to provide you with another metaphor (you know I love those), of which I hope that it will help you to understand both the complexity of the issue, as well as the current dilemma we are in.

Image 2: The producer of a movie (here Jerry Bruckheimer at the set of PoC4, img screenrant.com) is obviously an important guy, but do you know what he does? He is important, right, but how?

Imagine "Skeletal Muscle Hypertrophy" was the title of the newest blockbuster from tinseltown. It would be pretty easy for you to name the main protagonists, like Mr. L. Leucine, Mrs. A. Mpk, Mr. M. Tor and all the others. You could assign their names to the respective characters and would have at least a preliminary understanding of what their function in the plot of the movie may be. If you take a closer look at the film poster, you recognized another familiar name "a Big T production"... "Yo, cool! Big T that is the guy who has produced all those blockbusters. Man, this guy, must really know what he is doing...", you may be thinking, but tell me: Do you have any clue what guys like Jerry Bruckheimer actually do? No? Well, me neither. We know that without the producer there would not even be a movie, we know that he is of utmost importance and we know... or I guess, we automatically assume that guys like Jerry Bruckheimer (cf. image 2) have a fundamentally important role in the whole production process - I mean, wtf., they are called "producers" ;-)

In essence the situation for scientists (and science geeks like us) looking at the "the big T" is not much different from your's in front of the film poster:

1. We know that the loss of lean body and interestingly also bone mass is one of the fundamental characteristics of hypogonadism (below "normal" testosterone levels).
    
2. We know that restoring testosterone levels to normal via hormone replacement therapy (HRT) alone will oftentimes suffice to reverse / repair the muscle loss.
    
3. We know, or I should rather say, we like to believe that the granite hard muscle of 99% of the IFBB pro bodybuilders are built on supraphysiological levels of testosterone. 

But even if we take all that for granted (and I am not tackling the first two issues here, as they are pretty irrelevant for us). The question for average gymrats and science-geeks like us remains:  

"Does testosterone build muscle?"

Image 3: Granted, Prof. Hubert from Futurama would probably need some exogenous test, anyways. Luckily Bhasin et al. recruited young eugonadal men for their study ;-)

Imagine you were a brainy, not brawny scientist, someone like Professor Hubert from Futurama (cf. image 3). What would be the most obvious way to answer this vexing question? Well, that's easy: You sit down on your chair in the lab, inject some testosterone and just continue your overly intellectual day work. Before each of your weekly testosterone enanthate injections, you briefly hop into the DEXA scanner in the neighbouring medical department, measure your tighs and quads and take a blood sample to the lab. If after about half a year you still did not see any changes in body composition (DEXA), muscle size (tighs and quads), although your blood analysis reveal that your testosterone levels have been persistently elevated into super-physiological ranges, the answer to the question is... NO! If, however, you start noticing more and more muscle on your scrawny body, your little gut has disappeared, and you have to pay attention not to slam the lab-doors too hard, you know: Testosterone builds muscle!

Probably in view of the aforementioned "obstacles", there is only a single well-designed, and above all, extensively documented study in which researchers put our thought-experiment into practice. Obviously, the latter was no N=1 study, but involved a a group of 61 absolutely healthy eugonodal (= totally normal testosterone levels) young men (age 18-35y). Over a time-course of 20 weeks, the subjects received a weekly injection of an GnRH antagonist (to shut down endogenous testosterone production) and 25, 50, 125, 300, or 600 mg of testosterone enanthate (Bhasin. 2001). They did not exercise (in fact they were specifically advised to refrain from "strength training or moderate-to-heavy endurance exercise during the study"), did not increase their protein intake, did not co-administer any other performance enhancing drugs, yet still, they grew - well, to be precise that was the case for 3/5 of the subjects (cf. figure 1):

Figure 1: Changes in body composition measured by under water weighing (UWW) and DEXA after 20 weeks on the given amounts of testosterone enanthate; due to a -5% decrease in the fat-free mass to water ratio in the 125mg group (all other groups draw, not lost water) the highlighted UWW value is unrealiable (data calculated based on Bhasin. 2001)

As you can see in figure 1, only the subjects in the groups which received 125mg, 300mg, and 600mg testosterone enanthate per week were able to increase their lean muscle mass and decrease their body fat levels by literally lying on the couch (+5%, +15% and +37% increase in the free-to-fat mass ratio). The changes in the body composition of the 25mg and 50mg groups, on the other hand, were less favorable, to say the least (+37% and +16% body fat, as measured by DEXA in the 25mg and 50mg groups) - but how come, I mean testosterone does build muscle, right?

Figure 2: Changes in total testosterone (ng/dl) and IGF-1 (ng/ml) levels (left) and testosterone to IGF-1 ratio (right) of young eugonodal men after 20 weeks of GnHR antagonist + different doses of testosterone enanthate  (data calculated based on Bhasin. 2001).

If we take a look at the actual changes in the testosterone levels of the participants, the answer is quite obvious. With the exogenous suppression of the their own natural testosterone production by the Gonadotropin-releasing hormone (GnRH) antagonist, only 25mg or 50mg of testosterone enanthate per week, and corresponding reductions of both total and free testosterone by -57% and -46%, respectively, the poor sobs were essentially hypogonodal.

The complexities emerge: The testosterone-IGF1 connection

If you are the intelligent reader, I suppose you are, you will already suspect that I did included the relatively minor changes of the serum IGF-1 levels for a purpose - a purpose, those of you who have followed the last last installments of this series will probably already anticipate. After all, we do now know that testosterone does build muscle, but in the previous installments we have learned that a myriad of other factors, IGF-1 included, appear to do the same.

In view of the fact that I am still bone weary from New Year's Eve and do not want to compromise the quality of this series (and don't tell me it had no quality ;-), I will take a break here and catch up on this thought... tomorrow - I mean I know that it would be unfair to put you on the racks for a whole week ;-)