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).

Disappointing Results in 28-Day Creatine + β-Alanine Study: No Performance Benefits, No Muscle Gain, No Fat Loss, No Increase in Phosphocreatine & Carnosine in 32 Women

Let's take a closer look at the study and find how it was possible that two proven ergogenics "failed".

Creatine and beta-alanine belong to the few "proven ergogenics", but according to the latest study from the University of Pittsburg, the Texas Christian University, the University of Wisconsin – La Crosse and the Texas A&M University they are not as effective as some of us may think. Specifically the effects of beta-alanine which was tested in what you may call its "comfort zone", i.e. a graded exercise test on the cycle ergometer for VO2peak with lactate threshold determination, and multiple Wingate anaerobic capacity tests. And still, the overall results of the study is that there a "no consistent additive benefits of BA [beta alanine] and CRE [creatine] supplementation in recreationally active women.

If you are using creatine already try adding bicarbonate as extra-cellular pH-buffer

The Hazards of Acidosis

Build Bigger Legs W/ Bicarbonate

HIIT it Hard W/ NaCHO3

Creatine + BA = Perfect Match

Bicarb Buffers Creatine

Beta Alanine Fails to HIIT Back

In today's SuppVersity article, we are going to have a closer look at the study design, its outcomes and potential explanations for the absence of the highly desirable performance enhancing effects of these two (alleged) ergogenic powerhouses.

As you may know I am not a fan of beta alanine, anyway. Yet despite my alleged bias, I have to admit that the wingate tests the scientists used to determine the effects of the supplementation protocol may have been too short for BA to work. In the most comprehensive meta-analysis of the research to-date, Hobson et al. (2012) found that there are no ergogenic effects to beta alanine on exercises lasting less than 60s or more than 240s; and in the "ergogenic" 60-240s zone, the performance benefit is only 2.85%.

Figure 1: In view of the short study duration it's no wonder that there were no significant effects on body fat and lean mass, but the fact that the beta alanine only group actually gained fat after an initial high loss of body fat is still awkward - still, statistically significant was only the time effect, which tells you that exercise works (Kresta. 2014).

And as far as the absence of benefits of creatine are concerned. The results of the study are in line with previous experimental evidence like that presented by Green et al. who report in their 2001 article in the The Journal of Strength & Conditioning Research that...

"[...] short-term Cr supplementation does not enhance MP and PP during repeated upper-and lower-body Wingate tests when not accompanied by an increase in body weight." (Kresta. 2001)

Similarly, Hoffman et al. (2008) could not find perfomance benefits of short-duration beta alanine supplementation in college football players, what the scientists from the College of New Jersey did find, though was an increases training volume and reduces subjective feelings of fatigue in their highly trained subjects in response to the ingestion of 4.5g/day of beta alanine (Hoffman. 2008).

All in all, the results are thus less surprising than they appear to be...

... at least for those of you who don't believe in the unsustainable promises of the supplement industry, but rely on experimental evidence, only. For creatine, the scientists tested the wrong type of exercise. For beta alanine the exercise duration (60s) on the wingate tests was not long enough to show significant performance increases.

Figure 2: Non-significant (!) changes in carnosine (should increase with BA supplementation) and phosphocreatine (should increase with creatine supplementation) in the BA, BAC, CRE and placebo group (Kresta. 2014).

What the previous brief review of selected experimental evidence does not explain, though, are (a) neither the beta alanine, nor the creatine or combined supplementation lead to statistically significant increases in carnosine (via beta alanine) or phosphocreatine (via creatine), (b) the levels of phosphocreatine the high energy resource, that is believed to be responsible for most of the beneficial effects of creatine actually dropped after 2 weeks on maintenance dose of 0.1g/kg creatine, when it was administered after a 0.3g/kg creatine pre-load. These results stand in contrast to previous studies, like...

• Harris and colleagues (2001) who reported that β-ALA supplementation (3.2 g/day) resulted in a 42% increase in muscle carnosine levels after four weeks of supplementation not due to the fact that the carnosine levels didn't increase, but rather due to the fact that the scientists did not find statistically significant interactions among groups in muscle carnosine levels.
  
  As Kresta et al. (2014) point out, "the lack of statistical significance was apparently due to the large variability in muscle carnosine levels observed in response to β-ALA supplementation, assay variability, and/or inadequate sample size", so that "[m]ore research is needed to determine the effects of β-ALA supplementation on muscle carnosine levels in recreationally-active women" (Kresta. 2014).
• Greenhaff et al. (1994) or Harris et al. (1992) who found significant increases in phosphocreatine with similar preloading + maintenance creatine supplementation schemes as the one used in the study at hand, but yielded significantly higher and above all consistent increases in creatine of up to 40% . Results from the present study found non-significant increases in muscle PCr of up to 40%
  
  Again, Kresta et al. suspect that "the lack of significance may have simply been a result of the small sample size", but add that "it is also known that there is individual variability in response to creatine supplementation" (Kresta. 2014) - a fact that is imho unlikely to be a likely cause of the lack of effect in all subjects, though.

Overall it is thus difficult to determine the lack of consistence improvements in carnosine and phosphocreatine levels in the study at hand, it may yet, as Kresta et al. suggest also be possible...

A study by Everaert, et al. indicates that women have naturally lower carnosine levels (Evaerart. 2011 | see figure abvove). Previous studies, e.g. Tallon (2006), however, found no such difference which is interpreted by Harris et al. in their 2012 review as evidence that "that the apparent gender difference reported by Everaert et al. (2011) may have been simply due to a higher type I:II ratio in females in the voxel sampled." (Harris. 2012)

"[...]that sex may have played a role in response to creatine and/or β-ALA supplementation. In this regard, most studies on creatine and β-ALA supplementation have been conducted on males and there is some evidence that females may respond differently to creatine and/or β-ALA supplementation. For example, Fosberg and colleagues (Forsberg. 1991) reported that females had greater total creatine amounts relative to tissue weight; however, other studies show there is no difference between males and females (Forsberg. 1991; Stegen. 2014).

There are also some data suggesting that men may have greater muscle carnosine levels than women (Derave. 2002; Harris. 2012); however, a recent study showed sex did not have an effect on increasing carnosine levels with supplementation (Stegen. 2014). Additionally, Bex and coworkers (2014) reported that carnosine loading is more pronounced in trained versus untrained individuals" (Kresta. 2014).

It is thus possible, but imho again not very likely that the fact that the subjects in the study at hand were women and or their individual training status may have had and impact on the hardly existing response to creatine and/or β-ALA supplementation.

Creatine + bicarbonate appears to offer a superior synergism | learn why

In the end, it's yet not the increase in carnosine or phosphocreatine that's important for us. What we are looking for are performance increases, which were probably absent due to the selected tests, on which previous studies have already shown that creatine and beta alanine have failed before to produce significant performance increases (see previous elaborations on the non-existent effects of BA on 60s and >240s exercise and the issue with creatine and wingate tests), plus changes in body composition for which the four-week study period may simply have been too short.

Against that background I would like to point out that the study at hand does not indicate that either beta alanine or creatine are useful. What it does, thought, is to remind us of the fact that (a) you won't see results over night and (b) even beta alanine and creatine are exercise-specific ergogenics and won't boost your performance an each and every type of exercise to the same extent. Or what do you think are the implications? Comment on Facebook!

References:

• Bex, Tine, et al. "Muscle carnosine loading by beta-alanine supplementation is more pronounced in trained vs. untrained muscles." Journal of Applied Physiology 116.2 (2014): 204-209.
• Derave, Wim, et al. "Muscle carnosine metabolism and β-alanine supplementation in relation to exercise and training." Sports medicine 40.3 (2010): 247-263.
• Everaert, Inge, et al. "Vegetarianism, female gender and increasing age, but not CNDP1 genotype, are associated with reduced muscle carnosine levels in humans." Amino acids 40.4 (2011): 1221-1229.
• Green, J. Matt, et al. "The effects of creatine supplementation on repeated upper-and lower-body Wingate performance." The Journal of Strength & Conditioning Research 15.1 (2001): 36-41.
• Harris, Roger C., et al. "The absorption of orally supplied β-alanine and its effect on muscle carnosine synthesis in human vastus lateralis." Amino acids 30.3 (2006): 279-289. 
• Harris, R. C., et al. "Determinants of muscle carnosine content." Amino acids 43.1 (2012): 5-12.
• Hobson, Ruth M., et al. "Effects of β-alanine supplementation on exercise performance: a meta-analysis." Amino acids 43.1 (2012): 25-37.
• Hoffman, Jay R., et al. "Short-duration< i> β</i>-alanine supplementation increases training volume and reduces subjective feelings of fatigue in college football players." Nutrition Research 28.1 (2008): 31-35. 
• Kresta, Julie Y., et al. "Effects of 28 days of beta-alanine and creatine monohydrate supplementation on muscle carnosine, body composition and exercise performance in recreationally active females." Journal of the International Society of Sports Nutrition 9.Suppl 1 (2012): P17.
• Stegen, Sanne, et al. "The Beta-Alanine Dose for Maintaining Moderately Elevated Muscle Carnosine Levels." Medicine and science in sports and exercise (2014).
• Tallon, Mark J., et al. "Carnosine, taurine and enzyme activities of human skeletal muscle fibres from elderly subjects with osteoarthritis and young moderately active subjects." Biogerontology 8.2 (2007): 129-137.

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

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

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

To each his own high intensity training

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

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

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

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

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

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

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

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

80g Glycerol + 2L Water Decreases Body Weight in Athletes & Increases Overall Performance in Sedentary Subjects

If it does not make you as swole as the colorful ad promised it must not be working, right? The jury was not even any longer "out there" for glycerol, but a recent study makes you rethink, whether you just have to look in the right place to see the benefits.

Another of the "odd" Thursdays without an update from "Your's Truly" Adelfo Cerame. And since there is holiday today, over here, I even thought there would not be a SuppVersity Science Round Up today. But hey, you are lucky you (and Carl) got to work, so you can tune in live at 1PM EST, or even better, start listening live at 1PM in order not to miss the Strength and Hypertrophy Round Table!

As far the  topics for today's installment of the SuppVersity Science Round Up are concerned, you are actually only a couple of lines away from reading about one that's on the list:  The effects of glycerol on exercise performance. I don't have to tell you though that this is not everything. Other things I believe you may be interested in are...

• childhood obesity, physical education and attention at school
• wheat gluten hydrolysate and how they don't come up to the expectations early trials have raised
• ammonia accumulation brain-fog, toxicity, liver 'pathologies' and workout performance
• running next to a street entails 'particular downsides' ("particular" is to be taken literally, here ;-)
• homocysteine levels, mortality, cognitive impairment and more
• epigenetic programming by nicotine and different protein contents before birth

These topics alone obviously won't fit into a single episode, but by now you should be aware that the SuppVersity Science Round Up Seconds, which are always published one day after the show aired, will provide you with the things we have missed and additional information, suggested reads and graphs to the topics we covered...  apropos "won't fit in", since the above is not even everything I have up my sleeve, I thought it would be wise to take the glycerol news from the compilation and tackle it on its own, today.

Can the backbone of bad triglycerides really be good for you?

Glycerol, a 3-carbon sugar alcohol that provides the backbone of triglycerides and is naturally found in foods as a component of dietary fats (Burke. 2011), is one of those supplements that have been all the rage for some time, didn't produce the expected instant results everybody was looking for (in this particlar case mostly "skinbursting pumps" and have eventually, in the course of one or two cycles of the regular yearly reformulations of the pre-workout supplements, completely disappeared from the market. I was therefore surprised, when I hit onto a recent study by researchers from the Physical Education and Sport High School in Konya (Turkey) that was published in one of the latest issues of the Journal of Human Kinetics (Patlar. 2012).

Is glycerol save? There have not been any reported toxicity effects up to doses of 5g/kg body weight. Glycerol does accumulates in body fluids, with the exception of the brain and the eyes and increases osmotic pressure (which was the reason why people used it in "pump supplements"), as well as the total volume of water in the body. If anything was 'dangerous', or I should probably rather say 'detrimental' to it, it would probably be its energy content (it is subject to gluconeogensis in the liver), which puts you at 'danger' of adding one or another pound of body fat you would probably want to avoid. The results of the study at hand to yet suggest that this is not an issue as long as you are active.

In essence the study protocol is nothing extraordinary: Take a couple of guys, 40 in this case (age 22.82 ± 1.49 years), and feed and water them using...

• 1.2 g/kg body weight) followed by water (26 ml/kg body weight) to 10 sedentary individuals (GS) and 10 soccer players from the University team
• just plain water to the another 10 sedentary men and 10 soccer players

Conduct a baseline test in the course of which all subjects are familiarized with the exercise equipment, a cycle ergometer (Monark 814-E) and required to perform an...

• Astrand Cycle Ergometer Test and an
  
• Wingate Anaerobic Power Test
  *the videos are don't show the study participants

in a room that is kept at 30°C and a barometrical pressure of 668 mm-Hg. For the next twenty days, have half of the guys (athletic groups E and GE) perform a 20-m shuttle run test every day. And finally perform a second follow up to see and evaluate the individual and joint effects of exercise and glycerol supplementation.

What's a shuttle run? I guess those of you who play soccer or basketball will know similar drills (at least I have been tormented by my trainers with them before in both sports and could imagine they are also among the standard repertoire of football coaches - though I have never played that myself):

Video 1: The shuttle run is every trainer's darling and would actually make a nice conditioning workout to be implemented into your own routine - whatever it may you are training for (note: the video is a random pick from YouTube and has no relation to the study at hand).

"The subjects warmed up for several minutes by jogging followed by stretching. The test program was installed on the computer and  initiated. A single beep was emitted at regular intervals. The subjects had to complete a lap or shuttle (foot on or over the line) with each beep. If the subjects completed a lap early they had to wait for the beep before starting the next lap. A triple beep indicated the start of a new level with a slightly faster speed required to complete each  lap.

The subjects were encouraged to complete as many levels as possible. An observer monitored the progress of a given subject, recording each completed lap on the recorder form. The subjects were instructed to turn by pivoting and not to run in a wide arc. The test was terminated when a subject was two or more steps from the line, for two consecutive laps. The observer alerted the subject at this time." (Patlar. 2012)

The shuttle run was followed by a couple of minutes of walking to cool down and a stretching exercise. The data was collected, logged and archived for evaluation.

Now if we take a look at the results of this undertaking they are unquestionably somewhat surprising - at least at first sight (see figure 1). In absolute terms it looks as if we had an across the board, almost identical increase in performance due to the daily shuttle runs in the exercise groups and a surprisingly large beneficial effect of glycerol only in the sedentary subjects (which would by the way be in line with many of the more or less disappointing trials on the benefits of glycerol supplementation in athletes; cd. Burke. 2011):

Figure 1: Changes in anaerobic and aerobic performance - relative values on the left, absolute before (white) and after (black) on the right (Patlar. 2012)

If you take a look at the relative pre-post changes in figure 1 (left), instead of the absolute changes a more distinct picture emerges:

• the benefit the sedentary subjects derived from the supplementation looks even more pronounced,
• the aerobic performance of the soccer players in the exercise group did likewise benefit, albeit less than the performance of the sedentary group, and
• shockingly the increase in anaerobic performance which looks pretty much identical is not statistically significant, yet still reduced in the glycerol supplemented athletes in the exercise + glycerol group (note: there is an increase, it's only relatively smaller)

Now, we all know that hyperhydration goes hand in hand with an increase in body water. In figure 1 I did even plaster a huge red sticker with "hyperhydration" onto the graph to give you an idea of a possible mechanism of action. So, if we wanted to be fair, we would have to take that into account... what? Yeah and you want to know if it will make you blow up like a wale, right, ... so let's see:

Figure 2: Changes in body weight and relative power (watts per body weight) in the course of the trial (data based on Patlar. 2012)

If we assume you are a sedentary slob at 80kg you could in fact gain 1.6kg... whether that's only water or if there is some fat there, as well, I cannot tell. Notwithstanding, I mentioned in the red box on safety issues, already that you can hardly expect to down 80g of glycerol with an energetic value of 4.32kcal/g (i.e. 350kcal per day) extra everyday without gaining at least some weight (assuming all other parameters are constant; plus, this could be muscle as well - well, not if you don't work out, though ;-).

You cannot expect to lose weight, but surprisingly it may still happen that you do if you consume those 350kcal of glycerol with 2l water right before your daily shuttle run. 

At least this is what happened to the soccer players in the supplementation group: They lost 2.66lbs of body weight on average. "Weight" is the unfortunate key word here, because we have no way of telling whether that was muscle, water or fat weight, as the scientists did not measure that separately. But let's be honest, it appears more than unlikely that it is (a) water or (b) muscle. After all the relative anaerobic power increased equally in both groups and why on earth would you lose water when you hyperhydrate? Ok, it could be one of those counter-regulatory reactions our bodies love. That again should however lead to performance decrements we did not see... you see, it's like the idiomatic dog that's chasing his tail. Why don't you play ginea pig and let us know what happens ;-)

WADA Warning for competitive athletes: If you are a WADA controlled athlete, you better avoid glycerol. It may sound hilarious, but it is on the WADA list of prohibited supplements since 2012. Why? Well, the increase in blood volume could mask the use of testosterone and co. because the /dl count would be lower if the total blood volume is higher -- this is something the WADA officials consider call a "masking agent" (Wada. 2012).

How much do you need? Don't forget, for glycerol to work its hyperhydrating magic, you must consume it with similarly hilarious amounts of water as the subjects in the study at hand. According to van Rosendal et al. an effective protocol comprises 1-1.5 g/kg glycerol + 25–35 ml/kg of fluid. Assuming you weigh 80 kg you can't get way with anything below 80g of glycerol + 2l water! Obviously way more than what any of the hitherto no longer available 'pump' or pre-workout supplements contained (at least I have not come across one that has a 80g scoop and says "consume with at least 2l of water on the label" - have you?)

Bottom line: I want to be honest, I still have to make up my mind about the usefulness of this supplement. I guess what actually does the trick is the combination of hyperhydration + energy availability. I have been preaching more than enough about the importance of energy availability over the last couple weeks, so I don't think I have to go into any more details here.

What I do think, however, is that few of you will be aware of the 2008 paper by Judelson et al. in which they report that hydration status is a fundamental determinant of the endocrine response to exercise, with dehydration leading to inappropriately high cortisol and norepinephrine levels that go hand in hand with an attenuation of the testosterone response to exercise, and negative effects on carbohydrate and lipid metabolism (Judelson. 2008).

Since you should by now have gotten the notion that insufficient energy does exactly the same, glycerol could well provide a means to counter this ergolytic double whammy. Against that background it is however strange that the athletes could not derive any athletic benefit from it... and weight loss without dieting (at least they were advised to stick to their habitual diets)?

If there is one definitive message you can take home from this study, though, it would be related to the dosage advice in the blueish info-box on the top right of this last paragraph: You better know how to use a supplement correctly! And this goes for the manufacturers of supps, as well as for the consumers: While the formers should finally stop putting ingredients into their supps to have them on the label, consumers should learn to identify hilariously underdosed and thus useless 'kitchen sink supplements' that 'have it all', but in doses where 'all' does not produce 'any' effect... how you can do that? Easy: Just make sure you get your daily dose of educative SuppVersity posts every day!

References:

• Burke LM, Stear SJ, Lobb A, Ellison M, Castell LM. A-Z of nutritional supplements: dietary supplements, sports nutrition foods and ergogenic aids for health and performance--Part 19. Br J Sports Med. 2011 Apr;45(5):456-8. 
• Judelson DA, Maresh CM, Yamamoto LM, Farrell MJ, Armstrong LE, Kraemer WJ, Volek JS, Spiering BA, Casa DJ, Anderson JM. Effect of hydration state on resistance exercise-induced endocrine markers of anabolism, catabolism, and metabolism. J Appl Physiol. 2008 Sep;105(3):816-24
• Patlar S, Yalcin H, Boyali E. The Effect of Glycerol Supplements on Aerobic and Anaerobic Performance of Athletes and Sedentary Subjects. Journal of Human Kinetics. 2012; 34: 69-70. 
• Van Rosendal SP, Osborne MA, Fassett RG, Coombes JS. Guidelines for glycerol use in hyperhydration and rehydration associated with exercise. Sports Med. 2010 Feb 1;40(2):113-29.
• World Anti Doping Association. WADA Prohibited List 2010. < http://www.wada-ama.org/Documents/World_Anti-Doping_Program/WADP-Prohibited-list/2012/WADA_Prohibited_List_2012_EN.pdf > retrieved Nov. 01, 2012. 

Caffeine for Peak Performance: 2.7% Increase in Max-Power Can Make All the Difference | Plus: Timing Matters! "The Caffeine Buzz" Occurs 30 Min After Blood Levels Peak

Yes, caffeine "doping" may in fact allow you to show up at the office in time, even when you've overslept (only useful if your tiredness is not due to a caffeine-abuse induced lack of sleep, obviously).

It sounds unbelievable, but up to now most of the research into the effects of caffeine on single bouts of brief ( ≤30 s) maximal exercise, predominantly using 30-s sprint cycling tests, shows no effect:  Bell et al. (2001), Collomp et al. (1991), Glaister et al. (2012), ... the list goes on. None of these and a bunch of other studies found increases in sprint performance irrespective of the amount and mode of caffeine supplementation.

Until today, only Anselme, Collomp, Mercier, Ahmaidi, and Prefaut (1992) found a significant effect of caffeine on maximal anaerobic power output (Wmax), as derived from a series of maximal 6-s cycle sprint tests. Unfortunately, study by Anselme et al. (1992) has some limitations including: (1) the use of a mixed gender sample; (2) the use of a fixed (250 mg), rather than a body mass-relative caffeine dose; (3) the absence of serum caffeine analysis to confirm caffeine abstinence; and (4) the absence of a familiarisation trial.

You can learn more about coffee at the SuppVersity

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The Coffee³ Ad- vantage: Fat loss, Appetite & Mood

Caffeine Resis- tance - Does It Even Exist?

The aim of Mark Glaister and his colleagues from the St. Mary's University in Twickenham, UK, was thus to "repeat the study by Anselme et al. (1992), addressing the aforementioned issues, in an attempt to provide a clear answer as to whether caffeine has an effect on sprint cycling performance" (Glaister. 2014).

Update: The Latest on Caffeine, Exercise, Fat & Weight Loss | more

It would be beside if I tried to keep you on the tenterhooks. From the headline of today's SuppVersity article you know after all that the experiment was a success. Glaister and his colleagues whose experimental protocol involved fourteen male Strength and Conditioning and Sport Science students, who were regularly active in strenuous physical activity instead of average coach potatoes (that's important, because the results will differ), was a success.

The scientists were able to show that caffeine will actually increase peak anaerobic power output in a series of 6-s cycle ergometer sprints, separated by 5-min passive recovery periods.

Figure 1: Statistical significant performance increases occur only at torques that allow the subjects to perform at their individual maximal aerobic power output (W_max) - torques that were not used in previous studies (Glaister. 2014)

As you can see in Figure 1 the differences which reached statistical significance only on the latter of the sprints were not earth-shatteringly large, but they were there and could very well make the difference between victory and defeat in any competitive athlete.

With sprints caffeine timing will probably matter! While Cox et al. (2002) have shown that timing is of minor importance for endurance athletes, it does probably matter when exactly the amount of caffeine in your blood peaks vs. when it declines or just begins to rise for sprints and other short duration activities.

With the caffeine in the study at hand being ingested ~50 minutes before the workout (right after the blood draw that was conducted 1h before the exercise test), Glaister et al. probably hit the "sweet spot", of maximal "restlessneess" indica- tive of max. catecholamine levels of which Kaplan et al. found that it occurs after approx. 1h and thus 30 minutes after the serum caffe- ine levels peak (Kaplan. 1997)

Bottom line: As Glaister et al. point out, it is possible that the use of fixed-torque factors that didn't allow the subjects to attain their individual maximal anaerobic power (W_max) may explain the difference to previous trials. If you look at the corresponding graphs in the original paper, you will in fact see that significant differences were not achieved at fixed torques of 0.4 and 0.8 Nm/kg.

In addition, some of the previous studies used very short sprints of only 30s duration which may have been too short in total duration and to long (individually) for the subjects to even achieve their individual W_max.

Last but not least, the timing of the caffeine ingestion, which is also going to be a topic of a separate SuppVersity article in the near future (see sneak peak in the box to the right) may have been a performance limiting factor as well. Overall, the study at hand does yet provide further support for the WADA decision to put caffeine on the WADA 2014 Monitoring Program - as of now, it is yet not officially prohibited | Comment on Facebook.

References:

• Anselme, F., et al. "Caffeine increases maximal anaerobic power and blood lactate concentration." European journal of applied physiology and occupational physiology 65.2 (1992): 188-191.
• Bell, Douglas G., I. R. A. Jacobs, and K. Ellerington. "Effect of caffeine and ephedrine ingestion on anaerobic exercise performance." Medicine and science in sports and exercise 33.8 (2001): 1399-1403.
• Collomp, K., et al. "Effects of caffeine ingestion on performance and anaerobic metabolism during the Wingate test." International journal of sports medicine 12.05 (1991): 439-443.
• Cox, Gregory R., et al. "Effect of different protocols of caffeine intake on metabolism and endurance performance." Journal of Applied Physiology 93.3 (2002): 990-999.
• Glaister, Mark, et al. "Caffeine and sprinting performance: dose responses and efficacy." The Journal of Strength & Conditioning Research 26.4 (2012): 1001-1005. 
• Glaister, Mark, et al. "Caffeine supplementation and peak anaerobic power output." European journal of sport science ahead-of-print (2014): 1-7.
• Kaplan, Gary B., et al. "Dose‐Dependent Pharmacokinetics and Psychomotor Effects of Caffeine in Humans." The Journal of Clinical Pharmacology 37.8 (1997): 693-703.

Aerobic and Anaerobic Energy Costs of Strength Training: Single Set of Squats More Demanding than Bench Press, Triceps Extensions and Lat Pull Down Together!

Image 1: The squat - as intense as it is, it is no replacement for "aerobics"; more on squatting in the EMG Series

As a diligent student of the SuppVersity you will obviously remember yesterday's news on the potentially detrimental chronic increases in cortisol, Kirschbaum et al. (Kirschbaum. 2011) have observed in a group of 304 amateur endurance athletes. This raises the question, whether or not your 3-4 strength training sessions per week would not suffice as "aerobic exercise" - after all, most people are huffing and puffing much more after one sets of squats than after 45 min. on a recumbent bike. And even if you were not interested in increasing your aerobic performance, I assume it would be nice to know if squats really are so energetically intense as they feel, or, in other words, how much more energy you are expending doing squats vs. let's say triceps extension ;-)

And more generally, i.e. in view of the aerobic effect and energy expenditure in the course of a complete strength training session, it would be interesting to know, ...

1. how much total energy you were expending while benching, squatting, rowing and co., and
   
2. what the relation of aerobic to anaerobic energy expenditure was like during heavy resistance training.

Both questions have been a subject of scientific debates for quite some time. The measurement of blood lactate levels, as well as other methods to access total energy expenditure, the ratio of aerobic to anaerobic metabolism and the highly controversial contribution of increased energy expenditure after resistance training (EPOC) have been questioned lately (Robergs. 2007). Reason enough for Jefferson M. Vianna and his colleagues from Brazil and Portugal to take another, closer look at the total and relative energy costs of resistance training (Vianna. 2011), in order veri-/falsify previous empirical data.

As their measuring tool of choice, the scientists selected the oxygen deficit method (AOD), where the anaerobic contribution to the overall energy expenditure is estimated by linear extrapolation of the VO2 at supra-maximal intensities and the AOD is then calculated by subtracting the cumulative oxygen uptake (VO2Ac) from the estimated energy demand. As the scientists point out, thus...

[...] the VO2Ac represents the portion of energy obtained by aerobic processes and the AOD represents the portion of energy obtained by anaerobic processes [so that] their sum equals the total VO2 during exercise.

The subjects in the Vianna study were 14 male resistance trainees (26.6 ± 5.4 years, 1.77 ± 0.07 m height, 80.1 ± 11.4 kg body mass and 11.2 ± 4.6 % body fat) with at least one year of training experience on a protocol with three or more training sessions per week. After height, weight and several skin fold measures (chest, mid-axillary, tricipital, sub scapular, abdominal, supra iliac, and thigh) had been taken, the individual 1RM max for bench press, half squat, lat pull down and triceps extension were assessed. Afterwards, the scientists measured the VO2 for each of the four exercises at 12% and 20% of the previously established 1RMmax. The same procedure was repeated 48+h later at 16% and 21% of the individual 1RM max. Eventually (again 48+h rest), the subjects had to perform their bench presses, half-squats, lat pull downs and triceps extension at 80% of their 1RM. The gas the subjects expired during those sessions was collected and recorded by an open air circuit analyzer - you can see part of the results plotted in figure 1.

Figure 1: VO2Ac (ml/kg) and accumulated oxygen deficit (AOD; ml/kg) at 80% 1-RM for bench press, half squat, triceps extension and lat pull down (data adopted from Vianna. 2011).

If you recall what the scientists said about the interpretation of VO2Ac and the accumulated oxgyen deficit (AOD), it is pretty evident that there is a reason, why many trainees fear the the squat. After all, the "king of all exercises", as it is commonly referred to, has by far the highest total (cf. figure 1), as well as relative (cf. figure 2) anaerobic component of all four tested exercises.

Figure 2: Relative contribution of aerobic and anaerobic metabolism to overall energy costs of bench press, half squat, triceps extension and lat pull down at 80% of the individual 1RM (data adopted from Vianna. 2011).

Despite inter-individual variations this supremacy of the squat is statistically significant (p<0.05, indicating chances that this was an incidental observation are <5%).

Figure 3: Total energy demand (ml/kg) of bench press, half squat, triceps extension and lat pull down at 80% of the individual 1RM (data adopted from Vianna. 2011).

If we finally take a look at the total energy demands, the underlying reason for your panting becomes even more evident: Squatting is 3.3x more energetically demanding than bench pressing or doing triceps extensions or lat pulldowns.

The "king of all exercises" is in fact so energetically demanding that one set of squats at 80% of your 1RM max will still expend ~9% more energy than a workout consisting of bench presses, triceps extensions and lat pull downs! Nevertheless, while it cannot be excluded that squatting will indirectly improve your aerobic exercise performance, as well, in and out of itself, none of the tested exercises is suitable to replace what is commonly understood to be "aerobic" or "cardio training" - but hey, in view of what I have posted about the effects of HIIT training, lately, doing (regular) "cardio" training may be obsolete, anyways ;-)

Ripped & Buffed vs. Skinny and Sinewy: Training Velocity, not Load, Appears to be Sole Determinant of Exercise Induced Shifts from Slow- to Fast-Twitch Muscle Fibers.

Image 1: Who would you like to be?
And how do you train to achieve
his physique?

Sprinter or marathon runner? Ripped and buffed or skinny and sinewy? Although this is, after all, a question of muscle vs. fat, bone and tissue mass, it is upon closer examination as much a qualitative question, as it is a quantitative one - a question that may well be influenced by the way you train!

Unlike our adipose tissue which has almost unlimited capacity to grow, the size of our muscles appears to limited by a number of factors, among which the individual fiber-make-up, i.e. the ratio of slow-oxidative endurance-type fibers (type I) to fast-twitch type IIA (fast-oxidative glycolytic), and fast twitch IIX (fast glycolytic) seems to play an important role, when it comes to getting big and buffed or skinny and sinewy.

Figure 1: Slow- and fast-twitch faber composition in athletes and non-athletes (data based on Carrol. 1998; Widrick. 2002)

As the data in figure 1 goes to show, athletes, unlike untrained individuals, who have about the same amount of fast and slow-twitch fibers, exhibit discipline specific adaptations in muscle fiber composition, with sprinters having the lowest and middle distance runners the highest ratio of slow to fast twitch muscle fibers. According to data from Aagard and Andersen, Bergh et al. and Fry et al. (Berg. 1978; Aaagard. 1998; Fry. 2003), the range of slow to fast twitch fiber ratios extends from ultra-endurance runners with a 90:10 slow to fast twitch ratio down to weight lifters and sprinters with a minimum of 20:80 slow to fast twitch fiber ratio.

Muscle fiber type and weight loss: Contrary to what you may have guessed, or read elsewhere, obese patients with a higher amount of oxidative slow-twitch fibers have been shown to lose weight easier than their "heavier muscled" peers. In a 2002 study Tanner et al. report (Tanner. 2002):

With weight loss intervention, there was a positive relationship (r = 0.72,P < 0.005) between the percentage of excess weight loss and the percentage of type I fibers in morbidly obese patients. These findings indicate that there is a relationship between muscle fiber type and obesity.

Image 2: For someone who already got morbidly obese, a higher ratio of type II fibers may well be counter-productive if his/her overall goal is weight loss.

Another result of the same study, which could easily be misinterpreted as politically incorrect is the genetically determined higher raio of type II muscle fibers within the African American part of the female study population, which made it increasingly harder for these women to burn the fat. And just in case, you still wonder why a type I fiber, something obviously only skinny people have in excess would help with losing fat, just think about the term "oxidative muscle fiber" for a moment, then add to that the experimental observation that type I fibers have greater mitochondria volume densities than type II fibers (Sullivan. 1978) and you will realize that a highly oxidative muscle fiber is more valuable when it comes to burning fat than a glycolitic one, reagardless of whether or not the latter may "look" better ;-)

In a recent review of the literature Wilson et al. provide the following biological explanation for the differences that exist between endurance and strength athletes (Wilson. 2011):

[...], type I fibers have been observed to have both greater mitochondria volume densities as well as capillary-fiber contact length when compared to type II fibers.  In addition, mitochondria volume density was highly correlated (r = 0.99) with O2 diffusion coefficients across three different muscle groups (retractor, sartorius, soleus) suggesting greater aerobic capacity in type I fibers.

While type I muscle fibers will thus figuratively carry their owners in 80 days around the world, type IIX and IIA fibers exhibit a 10x and 6x greater peak power and a 4x and 3.3x greater contractile velocity than their oxygen-hungry slow twitch cousins.

Figure 2: Relative peak power and contractile velocity of fast twitch fibers vs. slow twitch fibers (data based on Wilson. 2011)

The reason that the two guys from image 1 do not only perform but also look completely differently, lies yet in the greater capacity of type II fibers for exercise-induced hypertrophy (Schoenfeld. 2000). The relative number of type II to type I fibers is thus of paramount importance, if you want to look like a sprinter - not like a marathon runner and if you want to lift heavy weights instead of running cross-country. Fry et al., for example found strong correlations (r = 0.94; almost "causative") between the percentage of type IIA fibers and 1 repetition max snatch performance in national caliber Olympic athletes (Fry. 2003). Now the obvious question is: "How can I influence my individual fiber composition, or is this simply genetically determined?"

It stands to reason that genetics is a major determinant of fiber composition, but, hardgainer or not, with appropriate training and nutrition everyone can - at least to a certain degree - shift his muscle fiber make-up from a slow-twitch oxidative to a fast-twitch glycolytic type, even without the use of clenbuterol and other beta-2 agonists which hav been shown to trigger respective shifts from type I to type II muscle fibers in a rodent model (Zeeman. 1988).

Training for shifts in fiber composition

From Wilson et al.'s review of the literature it becomes quite obvious that standard exercise regimen, like jump squats at either 30% or 80% do not provide satisfactory results for someone looking to increase the number, not the size of his glycolytic muscle fibers (Wilson. 2011). In a study by Liu et al. (Liu. 2008), a 5x3RM bench press protocol, performed 3 times per week for 6 weeks, on the other hand, triggered a shift within the type II fibers. It increased the percentage of type IIA fibers from 44.9% to 66.7%, but decreased the type IIX fibers from 33.4% to 19.5%, thus leaving the percentage of slow twitch type I fibers unchanged. A second group from the same study who used a more versatile routine, with the same 5x3 regimen on Mondays, 10x concentric-repetition bench press throws at 30% of their 1RM on Wednesday and 10 stretch-shortening type push-ups on Friday for 5 sets, each, were able to increase the number of type IIA muscle fibers (from 47.7% to 62.7%) without decreases in the number of type IIX fibers, but a profound -50% reduction of slow-twitch oxidative fibers (from 18.2% to 9.2%). Wilson et al. go on and cite several other studies that were able to show the modulatory (increase in type II, decrease in type I) effects of high-velocity contractions on muscle fiber composition (Wilson. 2011) and corroborate that results with findings from other studies which corroborate these results with ...

[...] findings that the percentage of type I fibers may be increased with various types of aerobic training protocols such as endurance cycle training (+12% Type 1) and long distance running (+17% Type 1), [where, on the other hand] studies indicate that sprint training may facilitate the change of slow twitch fibers to fast twitch fibers.

Interestingly, Hortobagyi et al. were able to show that laziness taken to the extreme, i.e. 3 weeks of knee immobilization, also reduced the amount of type I fibers (-9%) and increased the number of type IIX fibers (+11%) in 48 recreationally active men and women (Hortobagyi. 2000). These results should yet be treated with appropriate caution and I would strongly advice against lying on the couch to increase your propensity for muscle growth by decreasing the number of slow twitch and increasing the number of fast twitch muscle fibers, because "recreational activity", for most people, consists of aerobic type of exercises, playing soccer, tennis or whatever - all sports that by and out of themselves would trigger shifts towards a more oxidative (predominant type I) muscle composition. It is thus not surprising that refraining from such activities for 3 weeks would reverse those changes.

So how should you train, then?

In view of the paramount importance of speed, not load in the few experiments which challenge the hitherto established paradigm that muscle fiber composition was largely determined by genetics and transformation was possible only within type II fibers, i.e. from type IIA to type IIX and vice versa, the incorporation of respective training techniques, e.g. concentric-repetition bench press throws at 30% of your1RM, as they were used in the study by Liu et al. (Liu. 2008), into a more versatile hypertrophy-specific routine which would

1. trigger a hypertrophy response, on "classic" strength training days (like 3x5 or 3x8-10), and
2. increase propensity for growth, on "speed-rep" days with exercises like plyometric push-ups, concentric-repetition bench press throws at 30% 1RM, etc.

would appear to be the most reasonable way to train for anyone out there, who does not belong to the "genetic elite" of born sprinters.

Circuit vs. Classic Strength Training, Which System is More Metabolically Demanding? What are the Energetic Costs and Where Does the Energy Come From, Fat or Glucose?

When you build a circuit training routine, don't forget: There are lot's of metabolically demanding kettle- bell exercises to spice things up.

There are probably a dozen of reasons why people train. Many of them are really good: Wanting to stay healthy, to live longer, or to excel in your sports. Of others, however, I am not so sure whether they are actually worth pursuing, or do you think training to look like a walking stick to make it to the catwalk was a "good" motivation to go to the gym? Personally I don't think so and that's partly why I am hesitant to judge a workout by the amount of energy it may burn. So, before I get to the results of a recently conducted study from the University of Pernambuco/Federal University of Paraíba, the , University of Pernambuco, Recife and the University of Southern Maine (Aniceto. 2013), I short word of caution: NEVER let burning energy (let alone "calories") become the main goal of your workouts... well, unless you are one of those wanna-be-sticks and supplement cotton balls pre- and post-workout, obviously.

Classic or circuit training - does it even make a difference?

The experiment Aniceto et al. conducted was a randomized, controlled, cross-over trial. After having evaluated the body composition and strength the 10 normal-weight previously trained subjects (at least 6 months training experience with weights under their belt), the scientists assigned the subjects to perform two test workouts,  both workouts...

• 

  Suggested read: "Cardio & Weights - Mutual Exclusives or Synergists? Cardio "Before" and After Workouts Offers More Benefits Than Downsides for Strength & Mass" | read more

  were performed with a relatively light weight of 60% of the subjects individual 1-RM (=the maximal amount of weight the subjects could lift for one picture-perfect rep)
• lasted rougly 34 min.
• had a total of 24 working sets with 10 reps per set and 60s recovery in-between the sets
• all repetitions were performed with a TUT of 101, which means that both the con- and eccentric phase of the lift lasted for 1 second (the two "1"s) and there was no rest or stretch (the "0") in-between, and
• were performed in in the morning after a standardized breakfast consisting ofa bun of 50 g with a slice of cheese of 30 g and a glass of fruit juice of 200 ml (350 kcal; carbohydrates: 61.7%; proteins: 13.44% and lipids: 24.86%)

The only difference between the workouts was that in one session the subjects walked from one exercise, i.e. bench press, leg press (45º), seated row, leg curl, triceps pulley, leg extension, biceps curl, and adductor chair, to the other and performed only one set each (3x CIRCUITS total), while in the other, the CLASSIC condition subjects were advised to perform all three sets of an exercise subsequently before they switched over to the next one.

Suggested read: "Triple Your Energy Expenditure During Shuttle Runs + Learn Why Intensity and not Just Weight x Distance Counts" | read more

"The resting metabolic rate (RMR) has been calculated using the equation by Weir, being obtained by indirect calorimetry with the individual at rest after night fasting of 10-12 hours. The VO2 and the VCO2 were collected for 30 minutes; however, only the 10 final minutes were considered as measurement or the RMR. Estimation of aerobic energy expenditure (AEE, kj) and the rest interval (RIEE) the indirect calorimetry method was acquired through the VO2, being the caloric values of 21.1 kj and 19.6 kj, respectively." (Aniceto. 2013)

Using the lactate levels the scientists were also able to quantify the contribution of aerobic vs. anaerobic work and when they plugged all the data in the corresponding equations their result looked like this:

Figure 1: Anaerobic, Aerobic and Rest Interval total energy expenditure (EE in kcal; left) and lactate levels during the CIRCUIT and CLASSIC training regimen (Aniceto. 2013)

Now, if you look at the data and do the math, you will probably realize that the absolute energy expenditure was almost identical with a non-significant 4% = 5kcal advantage for the CIRCUIT group (185 vs. 180kcal). You may also realize that 5kcal/min is not exactly an earth-shatteringly high energy expenditure and this is not merely due to the relatively low workout intensity. And even with heavier weights, strength training is not best-suited to burn excess energy.

---

Strength training is not meant to "burn calories": Getting back to the point I made in the introduction, the findings of the study at hand confirm that weight training is not the ideal mean to become a scrawny. That does yet not mean that it cannot be the ideal complement to a calorically reduced (~20%) diet. On the contrary, unless you have to prepare for a show and got a deadline to meet, both CIRCUIT and CLASSIC resistance training regimen are equally suited to gear the weight loss you will be experiencing away from your precious muscle and towards those nasty fat stores you want to burn.

Outline of a powerful high resistance circuit training program (learn more)

If we also take into consideration that previous longer-term studies such as Alcarez et al. (2011) observed significant greater fat loss and muscle gains in likewise previously trained subjects  with an allegedly more intense (6 reps at 80-90% 1RM) CIRCUIT workout compared to its CLASSIC counterpart, it would thus be worth a try to go for the intense CIRCUIT on your next cut, although it may burn only 50% of the energy of a classic light intensity cardio or HIIT workout and have your diet take care of the rest. Everything else is only suitable for short term interventions and a recipe for overtraining and exercise dependence.

References:

• Alcaraz PE, Perez-Gomez J, Chavarrias M, Blazevich AJ. Similarity in adaptations to high-resistance circuit vs. traditional strength training in resistance-trained men. J Strength Cond Res. 2011 Sep;25(9):2519-27.
• Aniceto RR, Ritti-Dias RM, Scott CB, de Lima FFM, Pessôa dos Prazeres TM, do Prado WL. Acute Effects Of Different Weight Training Methods On Energy Expenditure In Trained Men. Rev Bras Med Esporte. 2013; 19(5/6): 181-185.