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Even female volleyball players are wo- men - no wonder they tend to undereat ;)

Usually we are learning about what makes us fat by looking at those who are fat. Studies on athletes like gymnasts and volleyball players, and what influences their body composition, on the other hand, are scarce. Reason enough for me to take a closer look at two thesis by graduates from the Georgia State University who analyzed the relationship between moderate, within day protein intake and energy balance on body composition of collegiate sand volleyball players (Richardson. 2014) and the relationship between daily protein distribution and body composition in elite gymnasts (Paszkiewicz. 2014) - research that could be relevant for both, men and women.

I guess many of you will remember that Ive written about gymnasts before - in July 2013, to be precise. In said article with the telling title "Do Chronic Energy Deficits Make Athletes Fat? The Longer & More Severe You Starve, the Fatter You Are. Irrespective of What the Calories-in-VS-Calories-Out Formula May Say" (read more) I analyzed the negative effects of "starvation" on body composition to highlight that simply not eating or eating like a bird is not going to give you the Shape cover model body, many girls are looking for.
In spite of the fact that the titles of the two studies and hand and the previously cited study by Deutz differ, the objectives are not very different:

• "The  purpose  of  this  study  was  to  simultaneously  assess  energy  balance  and
  protein  intake  to  determine  if  these  factors  are  associated  with  body  composition  in  a
  population of collegiate sand volleyball players." (Richardson. 2014)
• "The objective of this study was to determine the relationship between hourly EB and protein intake with body composition" (Paszkiewicz. 2014)

If you look at the exact ways the authors phrase it, it does yet become obvious that Richardson (2014) puts a greater emphasis on the amount of protein, while Paszkiewicz is, just like Deutz back in the day, very interested in the hourly energy balance (EB) and thus the time the subjects remain in a positive / negative energy balance.

Apropos subjects! In the gymnasts who participated in Paszkiewicz study were elite and highly
competitive athletes from several training gyms across the country. The information on their daily food intakes was elucidated by the means of secondary analyses that were performed on previously collected three-day food diaries and the interactions with body composition were calculated by comparing intakes and anthropometric measures (made with DEXA).

Table 1: ?Subject? Characteristics of the Gymnasts ? (N=?40; Paszkiewicz. 2014)?

Table 1 provides an overview of the subject characteristics. If you take a closer look, you will see that there is a pretty broad range from hardly any muscle to pretty muscular and from ripped to the shreds to average body fat.
If we take a closer look at the correlations Paszkiewicz found, some of you may be surprised to see that the relative carbohydrate intake (as percent of macronutrients) was not just positively associated with higher lean mass (see Figure 1), but also negatively with fat mass (R = -0.043).

Figure 1: Minimal, maximal and average energy balance in the gymnasts (left); positive correlates and correlation coefficients R of lean mass in 40 elite competitive female gymnasts (Paszkiewicz. 2014)

The amount of protein the gymnasts ate, however, was not significantly associated with increase lean mass. In fact, when we compare two groups, i.e. those with a high and those with a low protein intake, statistics inform us that "the higher protein group ha[s] a statistically significant lower FFM [fat free masss]" (Paszkiewicz. 2014).

Are high(er) protein intakes bad for gymnasts or, what?

Personally I suspect that this is due to a correlation between high(er) protein intakes, lower cabohydrate intakes (R = -0.595) and, most importantly, a reduced overall energy intake, which is associated with lower lean body mass and (listen up, ladies!), just as it has been reported by Deutz et al. previously, increased body fat % (reread the corresponding article from July 2013).

But why dont we have a look at the other study? Beach volleyball players are regarded as the epitome of health and sexappeal, so things could easily look different for them compared to the "frail" gymnasts, right? With a mean body fat % of 18% and a standard deviation ±7% the twelve women from the GSU sand volleyball team who participated in Richardsons study have a much healthier body fat percentage than the average, let alone extreme gymnast in the previously discussed study (we got to be careful here, because the BF% in the Richardson study was measured by body impedance and could thus easily be 5% off).
With a mean BMI of 22 kg/m², all female participants of the study were normalweight and consumed a diet with >1.94g protein per body weight (mean intake 132 ±52 g per day). An amount of protein most of the ladies spread across the day with a mean 26.06 (±10.51) g being consumed on every eating opportunity. Thats not yet the "SuppVersity suggested" amount of 30g of protein per meal, but its getting close, yet with an uneven distribution from AM to PM:

• 30g from 6-12 AM,
• 63g from noon to six PM,
• another 39g in the evening

In contrast to many average Janes and Joes, the study participants consumed almost half of the mean protein intake during mid-day, while their protein intake from 6 pm to midnight amounted to only 24(±23) % of their total daily protein consumption. Still, Richardson is right to point out that

"[...] protein intake distribution was skewed, on average, toward the latter half of  the  day  with  approximately  19%  of  protein  consumed  in  the  morning  and  34% consumed  in  the  evening." (Richardson. 2014)

Much to my surprise, the ladies in the beach volley ball team were similarly anorexic as their peers in the gymnast group. With -404  (±385) kcal/day the average energy balance was clearly negative; and even if the standard deviations indicate that this was not the case for all of the ladies, the athletes spent 17 hours, on average, in a catabolic energy balance state (< 0 kcal) on a daily basis.

A high relative protein intake was not associated with better body composition!

Interestingly, though, no significant correlation was found between energy balance per gram of protein consumption and body composition.

Table 2: Spearman’s Correlations: Six Zone Protein Intake and Body Composition (N=12; Richardson. 2014); FFM – fat free mass: FFM to Ht ratio – amount of FFM per cm of height; eating Opportunities – number of times athlete consumed calories; 24 Hour EB – net kcal at the end of the day (energy consumed less energy expended)

The picture that emerges from a regression analyses with respect to the relation of energy balance and protein variables is in fact dubious (see Table 2). The only significant correlations (bold) are a positive correlation between fat free mass (FFM) and protein intake late, and a negative correlation between fat free mass and protein intake early in the AM. A similarly confusing, yet at no time significant association arises for the fat mass, which correlates negatively (albeit with p = 0.678 statistically non-significantly) with the number of meals with a protein content of 25g or more.

Todays SuppVersity News will provide you with "confirmation" rather than "innovation", I suppose

With my recent article on the non-existance of protein-related osteoporosis (read more) and the short news post about the unique satiating effects of protein snacks (read more), theres been quite some protein lovin here at the SuppVersity as of late. Usually, I would try to avoid having yet another "protein article" in the same week, but for the most recent study on "Dietary Protein Distribution", I will make an exception and I bet, you wont mind! Why? Well, what about what follows the "Dietary Protein Distribution" in the title of said paper?

"...Influences 24-h Muscle Protein Synthesis in Healthy Adults"

By now, you may feel reminded of a recent review by Alan Aragon and Brad Schoenfeld (Aragon. 2013), the results of which (learn more) are not refuted by the results of the study at hand.
What the study does tell us, is simple: "The consumption of a moderate amount of protein at each meal stimulated 24-h muscle protein synthesis more effectively than skewing protein intake toward the evening meal." (Mamerow. 2014)

In other words: Dont cram all your protein into one meal!

I guess in view of past articles on related topics (e.g. "2x40g, 4x20g or 8x10g of Whey? Which Feeding Strategy Yields the Greatest Net Protein Retention?" | read more; or "Protein Timing Reloaded: A Reminder on the Importance of Repeated 20g Pulses for Optimal Protein Synthesis" | read more), this insight is not really going to surprise you.

Figure 1: Fractional protein synthesis at breakfast (left), when the difference was most pronounced (+30%) and rel. calculated 24h fractional protein synthesis (right) with EVEN vs. SKEWED protein distribution (Mamerow. 2014)

What may surprise you, though is the simple fact that this study, which was a joint venture of scienfitsts from the Division of Rehabilitation Sciences at the Department of Nutrition and Metabolism, and Department of Internal Medicine at the University of Texas Medical Branch and the Department of Food Science and Human Nutrition at the University of Illinois at Urbana (Mamerow. 2014) is the first study to conclusively show that spreading a relatively high protein intake (1.2g/kg body weight) across the day is superior to the large steak the average intermittent faster may be washing down with a triple protein shake in the evening.

With an average age of 37 years the 8 healthy, normal-weight adult men and women who participated in the study at hand were neither rodents, nor elderly individuals, and - contrary to what you may expect if you look at the italicized names of the Institutions the scientists who were involved in this study are working at - they were not in need of rehabilitation after an injury - they were average Joes (n = 5) and Janes (n= 3).

This is not about rodents, elderly people or injured athletes

As you can see in the overview in Table 1, the subjects consumed three square meals, i.e. breakfast, lunch and dinner in the course of the 7-day study period. The previous reference to intermittent fasting is thus obsolete - eating a minimal amount of protein in the morning and at noon is after all very different from eating nothing at all. 

Table 1: Seven-day mean energy and macronutrient intake in healthy adults consuming diets with an EVEN or SKEW protein distribution (Mamerow. 2014)

As the scientists point out, the total 24-h protein, carbohydrate, and fat consumption in the SKEW and EVEN conditions was not different.

"Both diets exceeded the RDA for protein [0.8 g/(kg d)] by ~50%. The SKEW diet met the RDA for protein during the evening meal alone. In all versions of the EVEN and SKEW menus used in this study, the animal-to-vegetable protein ratio was ~2:1." (Mamerow. 2014)

By using a 7-d crossover feeding design with a 30-d washout period, the scientists were thus able to measure the influence of protein timing, on the changes in muscle protein synthesis.

The latter was measured thrice, i.e. after each of the three meals, and used to calculate the twenty-four-hour mixed muscle protein fractional synthesis rates on days 1 and 7 after the ingestion of EVEN-ly or SKEW-edly distributed protein diets.
Reference:

• Aragon, Alan Albert, and Brad Jon Schoenfeld. "Nutrient timing revisited: is there a post-exercise anabolic window?." Journal of the International Society of Sports Nutrition 10.1 (2013): 5.
• Mamerow, Madonna M., et al. "Dietary Protein Distribution Positively Influences 24-h Muscle Protein Synthesis in Healthy Adults". J. Nutr. January 29, 2014 jn.113.185280 [ahead of print].

It always hits the (already) big ones.

A recent study that was conducted by a group of researchers from the Roehampton University, and the Universities of Northampton and Hull in London took an interesting and totally overdue approach to dispel the myths that revolve around the anti-obesity effects of breakfast. In the said study, a team of researchers recruited 37 participants who were assigned to one out of four groups on the basis of their body mass index (BMI) - normal weight BMI <25 kg/m² | or overweight/obese BMI > 25 kg/m² | habitual breakfast eaters | habitual breakfast omitters.

Subsequently, even the latter, i.e. the breakfast eaters were requested  to  eat  breakfast  for  an  entire  week. The BREAKFAST week was followed by a one week wash-out and an entire  week during which the subjects had to omit breakfast.
Over the course of the whole study period, all subjects hat do keep detailed 7-day food diaries, reporting what was consumed and the timing of consumption were completed for each breakfast condition.

Figure 1: Lean (left) and overweight (right) subjects react very different to breakfast skipping (Reeves. 2014)

As the data in Figure 1 already reveals, the total energy intake was significantly higher during the breakfast than the no breakfast week. But just as the scientists say, the present study did also reveal a "significant effects of timing on energy intakes": More energy was consumed during the afternoon in the no breakfast week compared to the breakfast week.

Timing and body weight, both make a difference!

In general, overweight participants consumed greater amounts of  energy than normal weight  participants (surprise ;-) in the early evening - the effect was even more pronounced for those of them who were regular breakfast omitters and thus used to feasting in the afternoon / evening.

Overall, this sounds as if having breakfast regularly was a very good idea, but unlike some people want to make you believe, the total energy intake does count. The same is yet also true for the amount of sugar, which skyrocketed in the overweight subjects in the no breakfast week. Running around on empty and being unable to tap into their affluent energy depots on the hips and around the waist, the insulin resistant (dont tell me about "healthy obesity!") overweight part of the study participants gravitated towards readily available energy intake.
References:

• Reeves, Sue, et al. "Experimental manipulation of breakfast in normal and overweight/obese participants is associated with changes to nutrient and energy intake consumption patterns." Physiology & Behavior | Available online 24 May 2014.

Is it true? Are we slaves to our internal clock? Is time really the only determinant of whether we are or arent hungry?

As a SuppVersity student you are well aware of the far-reaching effects our internal clock has on our metabolism (if you aint aware of this, Id suggest you review the Circadian Rhythm Series | click here). And if you are honest with yourself, you are probably also aware of the fact that it does not really matter if you eat 500kcal or 1,000kcal for breakfast, at 1:00pm - when you usually have launch - youre hungry... hold on! Are you actually hungry? If we define hunger as the urge to eat, the answer will probably be: Yes, you are! It would however be incorrect to assume that this "hunger" correlates in a predictable way with your current energy needs - otherwise obesity shouldnt be a problem, right?
The insight that overeating shouldnt be a problem if we were able to adjust our energy intake to our energy expenditura was probably also in the back of of Elizabeth C. Wuorinens and Katarina T. Borers heads, when the researchers from the Norwich University and the University of Michigan devised two experiments that would allow them to investigate the human urge to eat (the thing we call hunger) and its obvious correlation with regular eating times (Wuorinen. 2013). In that, the scientists were particularly interested, ...

• whether a central neural circadian oscillator activates hunger during the wakeful period of the day to produce a hunger acrophase at mid-day, and 
• if the hormonal consequences of meal eating and digestion and mechanical sequelae of digestive food processing inhibit this central hunger drive and thus provide cues for ultradian meal entrainment.

If you reread the hypothesis you will realize that there is a reciprocal relationship between the rhythmicity of your food intake and the expression of hunger-related hormones. When the clock says "Eat!" your Hunger hormones go up, you eat and you reinforce the already existing urge to eat in regular intervals (for most people approx. every 6h) or at fixed time points.

The clock controls when youre hungry. Its the master, the hormones are the slaves.

If thats correct, the magnitude of hunger of the 10 normal-weight post-menopausal women who participated in the Wuorinen study should be determined primarily by the circadian time of day and ultradian interdigestive episodes, and only secondarily, or even not at all by the inter-meal energy expenditure or the concentrations of ghrelin, leptin, or insulin. To verify that you have to collect hunger ratings in a realistic non-energy-deprived scenario and express them as function of time of day, interdigestive periods, the magnitude of energy deficit experienced since the previous meal, and plasma concentrations of ghrelin, leptin, and insulin.

Figure 1: Illustration of the experimental setup during the 2 trials (Wuorinen. 2013)

The illustration of the experimental protocol in Figure 1 goes to show you that Wuorinen & Borer used exercise (120min treadmill walking in study 1;  10 x 15min slow walking, 5-min rest (LOW) 10 x 7.5 minutes fast walk, 10min rest (HIGH)) as a means to modulate the energy expenditure.


On the day before each trial, a standardized meal consisting of 60% carbohydrates, 25% fat, and 15% protein containing 33% of weight maintenance calories was provided at 19 h. As the scientists point out, ...

"[...a]ll trial meals also had this macronutrient composition. Caloric intake during the trials was assessed from measurements of food provided and any food left uneaten. The inter-meal intervals (IMIs) were: IMI1 from the dinner at 19 h prior to the start of the trial day to breakfast on the day of the trial, IMI2 from the breakfast to lunch at 13 h, and IMI3, from the lunch to the dinner at 17 h. No adjustments in the quantity of food provided were made for energy expended during exercise." (Wuorinen. 2013)

The amount of food was standardized only in experiment 2 ("study 2" as the scientists called it). In experiment 1, the women were free to eat as much as they wanted.

Figure 1: Energy expenditure and intake (kcal) during study 1, total energy balance (middle) and hunger ratings (right) expressed in relative to of maximal score on the scale (Wuorinen. 2013)

A brief glance at the data in Figure 1 does yet suffice to see that working out did not compensate b any means for the exercise-induced extra-energy expenditure. If we do the math, this left the women in the exercise group with a -370kcal energy deficit, while the ladies who had been sitting around all day have already consumed 159kcal more than they would need.
In spite of the fact that the results of study 1 did already confirm the research hypothesis, the experiment in study 2, which had a longer study duration and standardized energy intakes, is probably of greater significance with with respect to the original research question.

Study 2 confirms the results of study 1 in a longer-term scenario w/ stand. energy intake

This time the subjects remained at the lab for a complete day, they performed two bouts of exercise at different intensities and received standardized meals and yet neither the exercise intensity, nor the inability to compensate for energy that was expended during the workouts had any effect on hunger-ratings - and that in the presence of increased ghrelin (=hunger hormone) levels.
All that would obviously suggest that the one thing that counts is and the entrained eating-frequency, if we did not know from previous SuppVersity articles that Taubesian "Exercise just makes you hungry"-hypothesis is fundamentally flawed.

For us, Wuorinens & Borers conclusion, which implies that the only thing that counts is that you eat, when its time to eat, irrespective of how your energy balance looks like, is intriguing, but not bulletproof. There is after all one major caveat, somebody without our understanding of the effects of exercise on hunger and satiety (such as Wuorinen & Borer ;-) would not realize: If the exercise induced modulation of the energy balance (calories in vs. calories out) have no orm as the reduced neuronal response in brain regions in response to endurance exercise (cf. Evero. 2012) would suggest, a negative effect on hunger-ratings and ad-libitum food intake, you cannot use an exercise intervention to modulate the energy balance in an experiment thats designed to identify the influence of circadian rhythms on individual hunger ratings.
References:

• Evero, Nero, et al. "Aerobic exercise reduces neuronal responses in food reward brain regions." Journal of Applied Physiology 112.9 (2012): 1612-1619.