Female Athletes' Body Composition Suffers From Chronic Energy Deficits: Effects of Energy, Protein, CHO Intake, Timing & Distribution in Gymnasts & Volleyball Players

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 I've 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 don't 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 Richardson's 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. That's not yet the "SuppVersity suggested" amount of 30g of protein per meal, but it's 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.