Gain DXA-Confirmed 3% Lean Mass Within ~12h, Glycogen Loading Does the Trick | Plus: Training on 'The Pill' & More...

The first December 2016 research update with studies that are relevant for both, women and men. I mean, who wouldn't want to get sign. more muscular in hours? I guess those who know that this is just an often overlooked measuring error.

Have you ever wondered about the accuracy of your DXA data? It's supposed to be "the gold standard", but you've learned only recently in the SuppVersity Facebook News that this is only the case if you measure at the same time of the day, identical hydration and - as a more recent study shows - even identical glycogen stores. What? Yes, that's right! You can make DXA-confirmed 3% gains in lean mass within hours. Simply by glycogen loading.

You're not interested in body fat data? Well, this is your lucky day. Today's installment of the short news will also discuss the latest study on the interaction between oral contraceptive and the adaptive response to exercise (Schaumberg. 2016).

Looking for more cutting edge exercise and supplementation science?

Vitargo, Red Bull, Creatine & More | ISSN'15 #1

Pump Supps & Synephrine & X | ISSN'15 #2

High Protein, Body Comp & X | ISSN'15 #3

Keto Diet Re- search Update | ISSN'15 #4

The Misquantified Self & More | ISSN'15 #5

BCAA, Cholos-true, Probiotics & Co | ISSN'15 #6

That's still not for you? Well, there's also the interaction between glucose, fructose and gastric emptying, which is of "urgent" (keyword: diarrhea vs. fastest glucose uptake) importance for endurance athletes (Shi. 2016).

• Diarrhea vs. fastest glucose uptake - How the glucose / fructose ratio can make all the difference (Shi. 2016) -- In their latest study, scientists investigated the effect of beverage osmolalities, carbohydrate (CHO) type and CHO concentration on gastric emptying in euhydrated subjects at rest.
  
  To this ends, the scientists measured the gastric emptying of water (W), and compared it to four glucose beverages containing either 2, 4, 6, or 8% glucose (2G, 4G, 6G, and 8G, respectively) and four sucrose (= 50% glucose + 50% fructose) beverages containing identical percentages, i.e. 2, 4, 6, or 8% of sucrose (2S, 4S, 6S, and 8S) in eight healthy subjects using the modified George double-sampling technique (Beckers. 1988).
  

  

  Figure 1: Mean gastric residual volume and gastric emptying rate in with standardized drinks with different carbohydrate sources (glucose or sucrose = 1:1 glucose : fructose) and volume (Shi. 2016).

  The scientists did not find significant differences in the gastric secretion volume among beverages across time and practically less relevant differences for the gastric residual beverage (GRBV) volume. What is interesting for you, on the other hand, is the scientists' observation that the gastric emptying rate (GER) was negatively correlated to the calories emptied (r=0.84) - and that the effect was more pronounced for glucose than for sucrose.
  
  

  

  Bad Fructose? Increased Glycogen Synthesis, Reduced Glycemia, Higher Glucose Oxidation | more

  What does that mean? Well, the answer is simple. Shi et al. provide more evidence of and a "novel" mechanism for the superiority of glucose + fructose mixes as intra- and post-workout shakes. Especially at high energy content, i.e. high levels of glucose and fructose in the drink, they are simply processed faster. Accordingly, it is not surprising that studies show benefits, not detrimental effects of adding the allegedly bad fruit sugar to a sugary intra- or post-workout shake. You can learn more about this in "Bad Fructose? Increased Glycogen Synthesis, Reduced Glycemia, Higher Glucose Oxidation" (more) and "Post-Workout Glycogen Repletion - The Role of Protein, Leucine, Phenylalanine & Insulin" (more).
  
  On the other hand, the risk of getting diarrhea may increase with each extra-gram of fructose in your intra- or post-workout beverage. The "optimal" 2:1 ratio for glycogen recompensation, I discussed in the previously cited article from 2013.
• Manipulation of Muscle Creatine and Glycogen Changes DXA Estimates of Body Composition (Bone. 2016) -- As the authors of the previously referred to study say dual x-ray absorptiometry (DXA) protocols are thought to provide a reliable measurement of body composition. In fact, however, their study shows that the accuracy will largely depend on the muscle glycogen content upon measurement (not so much on the level of creatine, though).
  
  How do they know? Well, the researchers had eighteen well-trained male cyclists (the training status is important, because the results may well differ for untrained or only recreationally active subjects) participate in a parallel group application of creatine loading (n=9) (20 g/d for 5 d loading; 3 g/d maintenance) or placebo (n=9) with crossover application of glycogen loading (12 v 6 g/kg BM/d for 48 h) as part of a larger study involving a glycogen-depleting exercise protocol. Body composition, total body water, muscle glycogen and creatine content were assessed via DXA, bioelectrical impedance spectroscopy, and standard biopsy techniques.
  

  

  Figure 2: Percent changes in leg lean and fat mass vs. baseline following glycogen depletion and creatine and glycogen loading with and without creatine (Bone. 2016).

  Their results confirm glycogen, as the primary determinant of ostensible gains. In fact, glycogen loading, both with and without creatine loading, resulted in substantial increases in estimates of lean body mass (mean +/- SD; 3.0 +/- 0.7 % and 2.0 +/- 0.9 %) and leg lean mass (3.1 +/- 1.8 %and 2.6 +/- 1.0 %) respectively. Cool? Well, the only bad news is that the DXA scan's body fat analysis will be messed up even more (+4.5% of body weight for the whole body, albeit - due to interpersonal differences - not statistically significantly) - in the end, you would thus always be told that you failed to achieve lean gains.
• Oral Contraceptive Use Dampens Physiological Adaptations to Sprint Interval Training (Schaumberg. 2016) -- Dampens? Yes, this means "the pill" will impair your fitness gains - in this case maximal oxygen uptake (VO2peak) and peak cardiac output (Qpeak), but there is good news, too... before we get to that, however, we should take a brief look at the study design.
  
  The scientists studied women taking oral contraceptives (OC | n=25) or experiencing natural regular menstrual cycles (MC; n=16) who completed an incremental exercise test to assess VO2peak, PPO, and Qpeak before, immediately after, and four weeks following 12 sessions of SIT. The SIT consisted of 10, one-minute efforts at 100-120% PPO in a 1:2 work:rest ratio.
  Now, the bad news I've already revealed is that the OC group saw a significantly reduced increase in VO2peak (OC +8.5%; MC +13.0%; p=0.010) and Qpeak (OC +4.0%; MC +16.1%; p=0.013), but the good news is...
  • the peak power output (PPO) increased to a similar extent in both groups (OC +13.1%; MC +13.8%; NS), and
  • intriguingly, the OC group showed more sustained training effects in VO2peak (OC -4.0%; MC -7.7%; p=0.010) on the follow up 12 weeks later
  Eventually, SIT did thus (i) improve peak exercise responses in all recreationally-active women, with (ii) women on OC responding significantly worse, yet (ii) more sustained (when the women seized training) than those with natural menstrual cycles.
  
  Therefore, the authors conclusion that "OC use should be verified, controlled for, and considered when interpreting physiological adaptations to exercise training in women" (Schaumberg. 2016) is obviously right - during detraining, on the other hand, it could be an advantage to be on oral contraceptives (needless to say that the adaptation conserving effects would have to be proven in a future study in which MC women would be put on OC after SIT).

Yes, I do suggest that it may be beneficial to drink these two and another two cups of coffee w/ lots of sugar after your workout - if you are an athlete, at least -- "Post-Workout Coffee Boosts Glycogen Repletion by Up to 30% and May Even Have Sign. Glucose Partitioning Effects" | more

So what's the verdict here? I guess there's no clear verdict on the headliner study. We will need a follow up to investigate whether a woman's "gains" (in this case in the conditioning department) can be conserved if she starts taking oral contraceptives during de-training. What we do know without another study, however, is that taking oral contraceptives during a training period will impair the normal physiological adaptation to sprint training.

And what about the other studies? Well, I guess if you can stomach it (and as of now, nobody complained), the previously discussed 2:1 glucose:fructose ratio is probably the "optimal" natural sugar supplement for your workout.  And if you want to measure your results, you better make sure you did not change your carb intake or had a glycogen depleting workout before doing a DXA scan | Comment!

References:

• Beckers, E. J., et al. "Determination of total gastric volume, gastric secretion and residual meal using the double sampling technique of George." Gut 29.12 (1988): 1725-1729.
• Bone, et al. "Manipulation of Muscle Creatine and Glycogen Changes DXA Estimates of Body Composition." Medicine & Science in Sports & Exercise: Post Acceptance: November 28, 2016 - doi: 10.1249/MSS.0000000000001174.
• Schaumberg, et al. "Oral Contraceptive Use Dampens Physiological Adaptations to Sprint Interval Training." Medicine & Science in Sports & Exercise: Post Acceptance: November 28, 2016 - doi: 10.1249/MSS.0000000000001171.
• Shi et al. "Effect of Different Osmolalities, CHO Types, and [CHO] on Gastric Emptying in Humans." Medicine & Science in Sports & Exercise: Post Acceptance: November 28, 2016 -doi: 10.1249/MSS.0000000000001176.

Blood Flow Restriction in Athletes: Did We Get it All Wrong? Must BFR-Cuffs be Worn After, not During Each Set?

If that's you. It's well possible that you've done it all wrong. Wearing the cuffs after the set may be the way to go!

You may have followed up on my recent suggested read in the SuppVersity Facebook News and read up on the recent scientific debate on the (non-)usefulness of training with cuffs (BFR-style). Well, after reading the full text of a recent study by Conor W. Taylor et al. (2015), I have to say: Maybe we have only done it wrong.

In their study, the researchers from the Loughborough University in Leicestershire had their subjects, 28 healthy trained males who were cycling 120 ± 66 km per week, all cuffed up after each set of a standardized sprint training. That's very dufferent from trying to sprint with cuffs on your legs (and usually reduced intensity) and appears to be - that's at least what the study results suggest - a potential game-changer.

You can learn more about BFR and Hypoxia Training at the SuppVersity

BFR, Cortisol & GH Responses

BFR - Where are we now?

Hypoxia + HIIT = Win?

BFR for Injured Athletes

Strength ⇧ | Size ⇩ w/ BFR

Training & Living in Hypoxia

Now, the good news is: The study involved both an acute and chronic exercise + BFR study of the effects of post-spring-training blood flow restriction.

• In Study 1, a between groups design determined whether 4 weeks (2 d/wk) of SIT (repeated 30 s maximal sprint cycling) combined with post-exercise blood flow restriction (BFR) enhanced maximal oxygen uptake (VO2max) and 15km cycling time trial performance (15km-TT) compared to SIT alone (CON) in trained individuals.
• In Study 2, using a repeated measures design, participants performed an acute bout of either BFR or CON. Muscle biopsies were taken before and after exercise to examine the activation of signalling pathways regulating angiogenesis and mitochondrial biogenesis.

As a science expert you'll know that study 2 probably wouldn't have been done if the results of Study 1 had not been encouraging.

Figure 1: Pre- to post-changes in VO2max (absolute, top-right), relative (top-left), MAP (bottom-left), 15k time trial (bottom-right) | I marked the individuals who saw positive and negative effects for you, the # on the buttons indicate the number of subjects who benefited (green) or saw no / detrimental effects (orange | original data from Taylor. 2015).

"Encouraging", in this case, means that the scientists observed a highly significant VO2max with post-workout BFR by 4.5% (P = 0.01) but was unchanged after CON.

So, does the increase in VO2 have anything to do with my gainz? Directly? No. But if there's an effect on hypertrophy it would - just as the effect on VO2 found in the study at hand - depend on increases in the stress response. Now, the more recent studies have shown that the necessary reduction in weight lifted when you do it with cuffs makes it practically useless for athletes. So, in conjunction with the study at hand, it's only logical to ASSUME that using the hypoxic stress after a set COULD provide an ADDITIVE stimulus (normal BFR training takes away from the regular stimulus, because it will.force athletes to refuce the weights and cannot fully compensate for that | see the results of this study.

The small advantage in the 15k time trial, on the other hand, did not reach statistical significance. That's "bad news", but the trend indicates that this might change with long(er) term studies.

Figure 2: Changes (%) in physiological and performance variables before and after CON and BFR training interventions (Taylor. 2015).

Whether that may change with a longer-term study will still have to be elucidated. What appears to be certain, though, is that the existing difference is not mediated by changes in PGC-1α, VEGF and VEGFR-2 mRNA expression between protocols. In fact, of all parameters the scientists tested to identify the underlying mechanism only the  mRNA levels of HIF-1α, the hypoxia-inducible factor 1-alpha, of which a recent paper by Lindholm and Rundquist (2015) highlights that it would be otherwise attenuated with long-term endurance exercise and thus lead to a blunted response to long-term exercise training (that's why rookies see fast results and pros only marginal results), differed significantly between groups (P = 0.04) 3 h after the cuffs were applied to the subject's legs.

Bottom line: While it is possible that the differences the scientists observed were triggered by BFR induced extra-stress (namely hypoxia, thus increases in Hypoxia-inducible factor 1-alpha), we will need additional (longer-term) studies to prove practically relevant improvements in time-trial performance and identify a definitive mechanism.

The benefits of blood flow restriction in healthy athletes may be less pronounced than the advocates would have it. If reversing the order of exercise and applying the cuff can solve that, this would be awesome!

With that being said, the results - although not fully convincing, yet - are quite exciting. After all, they really suggest that instead of training with cuffs, athletes who want to benefit from the additional low oxygen stress would have to copy the protocol of the study at hand and thus apply lower limb blood flow restriction within 15s of each sprint... or after each set of leg curls or squats? Well, that's a question we cannot answer based on the study at hand, but it would certainly be interesting to test what would happen if you applied the cuffs right after a set of biceps curls. Well, as you can see, there's still a lot of research to be done and as you know, the SuppVersity is going to be where you can learn about the results first ;-) | Comment on Facebook!

References:

• Lindholm & Rundqist, et al. "Skeletal muscle HIF-1 and exercise." Experimental Physiology (2015): Accepted Article.
• Taylor, et al. "Acute and chronic effect of sprint interval training combined with post-exercise blood flow restriction in trained individuals." Experimental Physiology (2015): Accepted Article.

Creatine & Caffeine Don't Mix!? True or False? Recent Study Sheds *New* Light on an Important Supplement Question

Will a small cup of coffee ruin the benefits you can derive from creatine supplementation? Sounds impossible, but it's a die-hard rumor with surprising scientific backing. Now, a new study could finally settle the debate.

As topic for the thesis he submitted to the faculty of the University of North Carolina at Chapel Hill in partial fulfillment of the requirements for the degree of Master of Arts at the Department of Exercise and Sport Science (Exercise Physiology), Eric T. Trexler selected the "Effects of Creatine, Coffee, and Caffeine Anhydrous on Strength and Sprint Performance" (Trexler. 2015).

This is, as some of you will immediately recognize, at least in parts, a variation of the age-old question, whether the purported diuretic effects of caffeine would impair the proven ergogenic effects of creatine. In that, it's a variation, because the domain of concern is not - as it is for most bros - solely restricted to resistance training, but extends beyond the investigated one-rep max on the leg press and into the realms of sprint performance. But let's tackle things one after the other.

You can learn more about creatine at the SuppVersity

Creatine Doubles 'Ur GainZ!

Creatine, DHT & Broscience

Creatine Better After Workout

ALA + Creatine = Max Uptake?

How is Creatine Metabolized?

Build 'Ur Own Buffered Creatine

As Trexel points out, the study at hand "sought to directly compare effects of caffeine-matched (300 mg) doses of caffeine anhydrous [CAF | that's basically the same stuff you will have in your pre-workout] and coffee [COF | that's ~3 cups of the beverage that many of you will be drinking on a daily basis] on strength and sprint performance, and to determine if CAF or COF intake modulate the effects of creatine (CRE) loading" (Trexel. 2015 | my emphasis).

Now, you propably don't need a PhD to be able to tell that creatine and caffeine are currently among the most popular and best proven nutritional ergogenic aids. What is odd, though, is that supplement companies have made a habit of packing both into one product, even though there's the long-standing suspicion that caffeine may blunt the effects of creatine.

Figure 1: Caffeine blunts the beneficial effects of creatine loading on dynamic torque production (Vandenberghe. 1996).

And there are in fact a handful of people who still believe this was a huge mistake - mostly, because early studies into the concomitant administration of both agents like a Vandenberghe et al. (1996) clearly indicate that "caffeine counteracts the ergogenic action of muscle creatine loading" by (in this particular study) blunting the increase in dynamic torque production. This study, as well as a study by Hespel et al. who observed opposing effects of creatine and caffeine on the relaxation time of skeletal muscle (creatine decreases it, while caffeine increases it), are reason enough for skeptics like Tarnpolsky et al. (2010) to say that "there is no rationale for their simultaneous use" even though they have to admit that evidence is inconclusive:

"Although there is little rationale for taking both caffeine and creatine simultaneously as ergogenic aids, some have reported that the acute consumption of both negated the ergogenic benefits." (Tarnpolksy. 2010).

On the other hand, there are good reasons to be skeptical about the implications of the Vandenberghe and Hespel studies, too. It must be taken into consideration, for example that...

• 

  When is the best time to take your creatine supplement? Before or after your workouts? Learn more in this Suppversity Classic: "Lean Mass Advantage of Post- vs. Pre-Workout Creatine Supplementation Confirmed. Older Trainees Benefit Most" | more.

  the short term creatine loading protocol used in Vandenberghe's study is no longer recommended and the assumption that caffeine + creatine won't mix in the long-run would require studies that investigate that in the long run,
• the study cross-over design of Vandenberghe's study in which the subjects received all three treatments in random order incorporated a 3-week washout period that was as follow up studies on the long-lasting effects of creatine supplementation suggest probably insufficient for the creatine levels to return to normal; after all, the minimal washout period for creatine is estimated to be ~4 weeks (Hultman. 1996)
• the Vandenberghe study used only one exercise to test the effects and does therefore hardly reflect the effects on real-world athletic performance, 
• lastly, many researchers have dismissed a potential interaction between creatine and chronic caffeine ingestion, because some of the early creatine studies with highly beneficial results have administered it dissolved in coffee/tea (Greenhaff. 1993; Birch. 1994); so have more recent studies that in which the effects of one of the previously mentioned nutraceuticals were tested (Smith. 2010; Lowery. 2013)

Against that background and in view of the fact that none of the long(er) term creatine supplementation studies that dominate the scientific landscape of the late 20th and early 21st century reports that coffee connaisseurs wouldn't let alone couldn't benefit from creatine supplements (Fukuda. 2010; Smith. 2010), the results of Vandenberghe's study would have to be reproduced even if there was no contradictory evidence from a 1998 study by Vanakosk et al. who observed no interaction between creatine and caffeine in their crossover study (Vanakosk 1998).

Where's the acute phase study data? While Trexel did an acute phase and a chronic supplementation study, I will not discuss the results of the acute phase study in detail, because the only effects Trexel observed in this part of the his experiment were (unsurprisingly)  the well-known beneficial effects of caffeine on acute exercise performance and even those were ... well, let's just say 'surprisingly inconclusive' - which means that I have seen much more significant benefits from caffeine in different experimental contexts (see Astorino. 2010 for a review).

To eventually find out if thousands of athletes competing in both aerobic and anaerobic sports are making a mistake, when they're pounding commercially prepared or self-made creatine + caffeine concussions, the initially mentioned study by Trexel was designed to find out if chronic coffee or caffeine anhydrous consumption blunts the ergogenic effect of creatine loading on strength and sprint performance outcomes.

Using subjects with previous resistance training experience, Trexel determined if caffeine (CAF) or coffeee (COF - both at 300mg caffeine per serving) intake modulates the effects of creatine (CRE) loading with 20 g/day, split between 4 servings by conducting the same battery of strength and sprint performance tests before and after the acute and chronic supplementation with coffee, creatine or caffeine or a combination of both (CRE + CAF or CRE + COF).

Unfortunately, the results of the by all means well-designed study are not clear enough to settle the debate once and for all even though, no inhibitory effects of caffeine or coffee on the ergogenic effects of creatine were observed. Personally, I'd say, though, that the total evidence would suggest that if there is an inteference, it's probably negligible in the long run.

But let's get back to the study at hand and what it tells or rather doesn't tell us about a possible interference: As you can see in Figure 2, Trexel's study does not suffer from the same problems as the previously cited study by Vandenberghe. It's not a cross-over study, so too little washout time is not a problem. On the other hand, the number of subjects (13-14 in each group) is not exactly high enough to make sure that the differences you're expecting will be significant if you happen to have selected a few creatine non- or hyper-responders that mess with your data.

Figure 2: Overview of the study design for the chronic supplementation study (Trexel. 2015)

An additional problem is the total length of the study. With only 5 days, we are - once again - not in the practically more relevant longer-term chronic supplementation time-frame that would mimic the way most of you are probably using their creatine products. Yes, previous studies have shown significant effects even in a time-frame as short as that, but you will also know that creatine is not only one of the few supplements where the effects may accumulate over weeks, but also one of the few where long-lasting effects of previous (even way beyond the previously cited wash-out period) can be safely excluded. Against that background one could (I know you're always smarter after you've done a study, so no smart-assing here) argue that it may not have been enough to pick subjects that had not taken creatine in the last three moths, but were not necessarily creatine naive.

What distinguishes creatine responders from non-responders? This question has still not been satisfactorily answered, but evidence from a 2004 study by Syotuik et al. indicates that different baseline creatine levels, the total muscle mass and the ratio of fast- to slow-twitch may determine whether you're going to see huge gains or no effect at all. To be more precise, Syotuik et al.'s observation suggest that ideally, you'd have a low baseline creatine level, lots of lean muscle and a high number of fast-twitch muscle fibers.

Yes, I know, being "creatine naive" does not sound like it could be important, but but in view of the anecdotal evidence that no "creatine cycle is as effective as the first one" as well as the scientific evidence that one's baseline creatine levels have a significant effect on whether you "respond" or "don't respond" to supplementation (Syrotuik. 2004 | see red box, as well), it could at least partly explain why the results of the study are somewhat inconclusive.

Figure 3: If we go by serum creatine levels it would seem as if caffeine wasn't a problem - specifically if it comes from coffee. Unfortunately, serum creatine is pretty irrelevant and the performance data in form of changes in total work and the number of reptitions on the leg press and bench showed no signifant intergroup difference. Now this would suggest that it's not problem to take creatine with coffee or caffeine, but convincing evidence that caffeine does not impair the beneficial effects of creatine would require these beneficial effects to show (data after chronic suppl. from Teaxel. 2015).

And with "inconclusive" I am attributing the data in Figure 3 which tells you - more than anything else - that neither creatine nor caffeine produced a significant performance increase in any of the relevant parameters over the five-day study period.

Only the increase in plasma creatine was statistically significant. That's nice, because it shows that mixing your creatine into instant coffee, which is what the guys in the coffee + creatine group were told to do, appears to rather boost than hamper the intestinal absorption of creatine. Eventually, however, this information is irrelevant, because it is the increase in intramuscular phosphocreatine stores that's driving the (not observed) performance benefits - not an increases in serum creatine.

Another die-hard creatine myth based - just like the myth from the study at hand - on the results of a single study (and this time without rational hyopthesis to explain the results) is that creatine would increase DHT and thus trigger hair loss and prostate cancer | Learn more about this bogus.

So are we left with nothing? Not exactly, after all, the study confirmed that caffeine and coffee both have their merit as acute phase ergogenics. It's correct, though, that this does not tell us, if caffeine will blunt the beneficial effects of creatine in either the short or the long run. In this respect, we are thus about as wise as before; and that in spite of the fact that Trexel is obviously right when he writes that "[t]he addition of CAF and COF did not appear to influence performance outcomes of CRE supplementation" (Trexel. 2015). In view of the fact that no significant effects of creatine supplementation were observed, we still need future long(er) term studies that combine coffee / caffeine + creatine and tests it against placebo and creatine alone - maybe even in different dosages - to answer the question whether it does or doesn't matter if you consume caffeine when you're "on" creatine once and for all | Comment on FB!

References:

• Astorino, Todd A., and Daniel W. Roberson. "Efficacy of acute caffeine ingestion for short-term high-intensity exercise performance: a systematic review." The Journal of Strength & Conditioning Research 24.1 (2010): 257-265.
• Birch, R., D. Noble, and P. L. Greenhaff. "The influence of dietary creatine supplementation on performance during repeated bouts of maximal isokinetic cycling in man." European journal of applied physiology and occupational physiology 69.3 (1994): 268-270.
• Fukuda, David H., et al. "The possible combinatory effects of acute consumption of caffeine, creatine, and amino acids on the improvement of anaerobic running performance in humans." Nutrition research 30.9 (2010): 607-614.
• Greenhaff, Paul L., et al. "Influence of oral creatine supplementation of muscle torque during repeated bouts of maximal voluntary exercise in man." Clinical Science 84 (1993): 565-565.
• Hespel, Peter, B. Op‘t Eijnde, and Marc Van Leemputte. "Opposite actions of caffeine and creatine on muscle relaxation time in humans." Journal of Applied Physiology 92.2 (2002): 513-518.
• Hultman, E., et al. "Muscle creatine loading in men." Journal of applied physiology 81.1 (1996): 232-237.
• Lowery, Ryan P., et al. "Effects of 8 weeks of Xpand® 2X pre workout supplementation on skeletal muscle hypertrophy, lean body mass, and strength in resistance trained males." J Int Soc Sports Nutr 10.1 (2013): 44.
• Smith, Abbie E., et al. "The effects of a pre-workout supplement containing caffeine, creatine, and amino acids during three weeks of high-intensity exercise on aerobic and anaerobic performance." J Int Soc Sports Nutr 7.10 (2010): 10-1186.
• Syrotuik, Daniel G., And Gordon J. Bell. "Acute Creatine Monohydrate Supplementation: Adescriptive Physiological Profile Of Responders Vs. Nonresponders." The Journal Of Strength & Conditioning Research 18.3 (2004): 610-617.
• Tarnopolsky, Mark A. "Caffeine and creatine use in sport." Annals of Nutrition and Metabolism 57.Suppl. 2 (2010): 1-8.
• Trexler, Eric T. Effects of creatine, coffee, and caffeine anhydrous on strength and sprint performance. Diss. THE UNIVERSITY OF NORTH CAROLINA AT CHAPEL HILL, 2015.
• Vanakoski, Jyrki, et al. "Creatine and caffeine in anaerobic and aerobic exercise: effects on physical performance and pharmacokinetic considerations." International journal of clinical pharmacology and therapeutics 36.5 (1998): 258-262.
• Vandenberghe, K., et al. "Caffeine counteracts the ergogenic action of muscle creatine loading." Journal of applied physiology 80.2 (1996): 452-457.

750kcal/day Deficit Approach to "Cutting" Beats Cautious 300kcal/day Deficit: Almost 2kg Fat in 4 Weeks + No Decline in Testosterone or Muscle Loss in Lean Athletes

Even in lean athletes dieting does not have to cost muscle mass.

One of the commonest reasons people don't achieve the physique of their dreams is fear! The fear of losing muscle weight on a "cut" and the fear of gaining fat weight on a "bulk". The study at hand confirms: There is no reason to be afraid of cutting.

In the course of the four-week cutting period in the study at hand, the subjects, 20-35 year-old national and international level Finnish track and field male athletes from jumping and short distance running events (e.g. 100-200m) with already low body fat percentages lost another ~2% body fat, and no muscle in spite of a highly significant 750kcal/day deficit.

What about fasting and eating / skipping breakfast - does it hamper or promote weight loss?

Breakfast and Circadian Rhythm

Does Meal Timing Matter?

Breakfast & Glucose Metab.

Breaking the Fast, Cardio & the Brain

Does the Break- Fast-Myth Break?

Breakfast? (Un?) Biased Review

In contrast to the guys who had been randomized to the "high energy deficit" group, the guys who ended up in 300kcal/day deficit group aka the"afraid of losing muscle group", lost neither muscle nor fat weight - and I bet, they did not feel significantly less hungry.

Figure 1: Changes in body fat and lean mass in grams (Huovinen. 2014)

The data in Figure 1 which is the outcome of a controlled 4-week study in the course of which the subjects were advised to cut fat and carbs and keep their protein intake stable make a clear statement: Trying to cut with a caloric deficit of only 300kcal/day is a waste of time" ... at least for someone who starts with a body fat percentage of only 10%, as the subjects in the study at hand did.

Figure 2: Pre- and post protein, fat and carbohydrate intake (in g/kg/day) according to subjects' food logs which had to be kept for the whole study period (Huovinen. 2014)

As you can see in Figure 2 the subjects did as they were told and cut back on both fat and carbohydrates - in conjunction with the physical activity this is certainly the key to lean body mass and performance maintenance.

"The  counter-movement  jump  and  20-m  sprint  time  improved  consistently  (p  ≤ 0.05)  only in HWR (-700kcal/day), by 2.6 ± 2.5 cm and 0.04 ± 0.04 s, respectively. Finally, athletes with a fat percentage 10% or over at the baseline were able to preserve FFM." (Huovinen. 2014)

Whether that's also the reason that the scientists did not observe significant differences in serum testosterone in either of the two groups is questionable (Testosterone / cortisol: 33.6 (pre) vs. 38.3 (post)), though - especially in view of previous results like those I wrote about in the following two articles:

• "High or Low Protein Intakes Have Profound Influence on Testosterone, SHBG, Estrogen, Cortisol & Co?" (learn more) and 
• "High Protein Diets Don't Counter Anti-Anabolic Effects of Low Energy Intake" (learn more)

It's more likely that the 27.1kcal/kg of body weight, the subjects in the 700kcal/day diet consumed were still more than enough to cover the basic energy requirements. With an average body weight of ~75kg that's still more than 2,000kcal and thus way more than the average starvation diet of the average overweight person will deliver.

Learn more about dieting, here.

Bottom line: The results of the study support the use of short, but relatively intense dieting periods. Dieting periods with a 750kcal/day deficit - a deficit that is still only -24% below the baseline intake of the athletes.

What's yet also important is that we don't forget that a dieting principle that works for lean athletes will not necessarily work for an overweight or obese person. The general idea to cut back by 24% and not just 12% (to avoid muscle loss) from carbohydrates and fats while maintaining an optimal protein intake of ~2g/kg body weight is yet something I can whole-heartedly recommend to heavier dieters, as well.

Reference:

• Huovinen et al. "Body Composition And Power Performance Improved After Weight Reduction In Male Athletes Without Hampering Hormonal Balance." Journal of Strength and Conditioning Research Publish Ahead of Print DOI: 10.1519/JSC.0000000000000619