NAP: Energy Balance and Body Composition (2014)


Maestu J, Eliarim A, Jurimae J, Valter I, Jurimae T. Anabolic and Catabolic Hormones and Energy Balance of the Male Bodybuilders During the Preparation for the Competition. J Strength Condition Res. 2010; 24 (4): 1,074-1,081.

Study Design:
Non-Randomized Controlled Trial
C - Click here for explanation of classification scheme.
Quality Rating:
Neutral NEUTRAL: See Quality Criteria Checklist below.
Research Purpose:

To determine the simultaneous effect of calorie intake, energy expenditure and the biochemical parameters that affect the anabolic-catabolic balance in male bodybuilders during their preparation for a target competition.

Inclusion Criteria:
  • Male national- and international-level amateur participating in the European Championships
  • Free of disease
  • Not using any drugs or anabolic steroids during the study and during the previous two-year period.
Exclusion Criteria:

Use of drugs or anabolic steroids during the study and previous two years.


Description of Study Protocol:
  • Recruitment: Participants in the European Championships
  • Design: Non-randomized control trial 
  • Intervention: Energy restriction.

Statistical Analysis

  • Friedman analyses of variance by ranks were used to examine changes because the data were not normally distributed
  • The Wilcoxon matched-pairs signed rank test was used where post-hoc analysis was relevant
  • The Wilcoxon matched-pairs signed-rank test was also used to assess the differences between the measured variables in bodybuilders and control groups
  • Kendall rank correlation coefficients were used to evaluate associations among different variables of interest. 
Data Collection Summary:

Timing of Measurements

11 weeks, nine weeks and three days before the championships.

Dependent Variables

  • Body mass: Measured to nearest 50 gm with medical balance scale
  • Height: Martin metal Anthropometer to nearest 0.1 cm
  • Body composition: DXA with the Lunar DPX-L total body scanner
  • Fasting blood: After 10 hours' fast between 7:30 a.m. and 8:00 a.m.
  • Food intake: Consecutive three-day diaries; average of the three days used
  • Energy expenditure: Method of Bouchard plus self-report of total training volume and amount of aerobic training and strength training.

Independent Variables

Negative energy balance together with increased energy expenditure (ERG).

Control Variables

No change in eating or training pattern (CG).

Description of Actual Data Sample:
  • Initial N: 14 males
  • Attrition (final N): 13
  • Age: 28.29±10.27 years in ERG and 22.42±2.4 years in controls
  • Ethnicity: Not described
  • Anthropometrics: 9.6±2.3% body fat in ERG and 11.96% in CG. Fat mass was 7.4±2.1kg in ERG and 9.65±2.39kg in CG. 
  • Location: Estonia.
Summary of Results:

Other Findings

  • Total training volume was significantly higher during each week of the study in ERG, with no significant difference in the amount of the total volume of strength training between the two groups. Strength training was about 53.5% at T1 and was reduced to about 39% by T3 with a concomitant increase in aerobic training in ERG, while in CG the amount of strength training was not changed and was in the range of 65% during the entire study. 
  • No significant differences were seen in the consumed food components during the study in either group. A tendency to decrease intake of carbohydrates (CHO) was found at T3 in ERG compared to T1. Protein, CHO and fat intakes were approximately 28%, 60% and 15% of total calories in the ERG, respectively, and 25%, 60% and 12% in the CG. The energy intake of the ERG decreased about 13% from T1 to T3, but it was not statistically significant. The energy expenditure of the ERG was significantly higher at T2 and T3. The intake of protein tended to be higher in ERG compared to CG (P=0.073) at T1. The increases in energy expenditure and decrease in energy intake resulted in negative energy balance at about 783kcal per day at T3 in ERG. 
  • Body mass and body fat percentage of ERG were significantly decreased during the study period (from 82.9±9.3kg to 78.8±8.4kg and from 9.6±2.3% to 6.5±1.5%, respectively), while no significant changes were observed in CG. 
  • In ERG, IGF-1 and insulin decreased significantly during the 11-week weight reduction (P<0.05). In T2 and T3, testosterone was significantly decreased in ERG when compared to T1. No significant changes were seen in CG except a significant increase in testosterone concentration from T2 to T3. 
  • There were significant correlations in the change of IGF-1 and the changes in insulin, fat mass, lean body mass and body mass (R=0.652-0.741; P<0.05). Changes in insulin were significantly related to changes in fat mass and lean body mass (R=0.630-0.725; P<0.05). Changes in IGFBP-3 were significantly related to changes in IGF-1 and lean body mass (R=0.689 and R=0.697, respectively; P<0.05). 
Author Conclusion:

Severe energy restriction to extremely low body energy reserves decreases significantly the concentrations of three anabolic pathways despite high protein intake. 

Funding Source:
Estonian Science Foundation
Reviewer Comments:

It was not clear if the participants were already on the energy restriction at the start of the study and if that was how it was determined the group they were in. 

Quality Criteria Checklist: Primary Research
Relevance Questions
  1. Would implementing the studied intervention or procedure (if found successful) result in improved outcomes for the patients/clients/population group? (Not Applicable for some epidemiological studies) Yes
  2. Did the authors study an outcome (dependent variable) or topic that the patients/clients/population group would care about? Yes
  3. Is the focus of the intervention or procedure (independent variable) or topic of study a common issue of concern to dieteticspractice? Yes
  4. Is the intervention or procedure feasible? (NA for some epidemiological studies) Yes
Validity Questions
1. Was the research question clearly stated? Yes
  1.1. Was (were) the specific intervention(s) or procedure(s) [independent variable(s)] identified? Yes
  1.2. Was (were) the outcome(s) [dependent variable(s)] clearly indicated? Yes
  1.3. Were the target population and setting specified? Yes
2. Was the selection of study subjects/patients free from bias? Yes
  2.1. Were inclusion/exclusion criteria specified (e.g., risk, point in disease progression, diagnostic or prognosis criteria), and with sufficient detail and without omitting criteria critical to the study? Yes
  2.2. Were criteria applied equally to all study groups? Yes
  2.3. Were health, demographics, and other characteristics of subjects described? Yes
  2.4. Were the subjects/patients a representative sample of the relevant population? Yes
3. Were study groups comparable? ???
  3.1. Was the method of assigning subjects/patients to groups described and unbiased? (Method of randomization identified if RCT) ???
  3.2. Were distribution of disease status, prognostic factors, and other factors (e.g., demographics) similar across study groups at baseline? ???
  3.3. Were concurrent controls or comparisons used? (Concurrent preferred over historical control or comparison groups.) Yes
  3.4. If cohort study or cross-sectional study, were groups comparable on important confounding factors and/or were preexisting differences accounted for by using appropriate adjustments in statistical analysis? N/A
  3.5. If case control study, were potential confounding factors comparable for cases and controls? (If case series or trial with subjects serving as own control, this criterion is not applicable.) N/A
  3.6. If diagnostic test, was there an independent blind comparison with an appropriate reference standard (e.g., "gold standard")? N/A
4. Was method of handling withdrawals described? Yes
  4.1. Were follow-up methods described and the same for all groups? Yes
  4.2. Was the number, characteristics of withdrawals (i.e., dropouts, lost to follow up, attrition rate) and/or response rate (cross-sectional studies) described for each group? (Follow up goal for a strong study is 80%.) Yes
  4.3. Were all enrolled subjects/patients (in the original sample) accounted for? Yes
  4.4. Were reasons for withdrawals similar across groups? N/A
  4.5. If diagnostic test, was decision to perform reference test not dependent on results of test under study? N/A
5. Was blinding used to prevent introduction of bias? No
  5.1. In intervention study, were subjects, clinicians/practitioners, and investigators blinded to treatment group, as appropriate? No
  5.2. Were data collectors blinded for outcomes assessment? (If outcome is measured using an objective test, such as a lab value, this criterion is assumed to be met.) Yes
  5.3. In cohort study or cross-sectional study, were measurements of outcomes and risk factors blinded? N/A
  5.4. In case control study, was case definition explicit and case ascertainment not influenced by exposure status? N/A
  5.5. In diagnostic study, were test results blinded to patient history and other test results? N/A
6. Were intervention/therapeutic regimens/exposure factor or procedure and any comparison(s) described in detail? Were interveningfactors described? Yes
  6.1. In RCT or other intervention trial, were protocols described for all regimens studied? Yes
  6.2. In observational study, were interventions, study settings, and clinicians/provider described? N/A
  6.3. Was the intensity and duration of the intervention or exposure factor sufficient to produce a meaningful effect? Yes
  6.4. Was the amount of exposure and, if relevant, subject/patient compliance measured? Yes
  6.5. Were co-interventions (e.g., ancillary treatments, other therapies) described? N/A
  6.6. Were extra or unplanned treatments described? N/A
  6.7. Was the information for 6.4, 6.5, and 6.6 assessed the same way for all groups? N/A
  6.8. In diagnostic study, were details of test administration and replication sufficient? N/A
7. Were outcomes clearly defined and the measurements valid and reliable? Yes
  7.1. Were primary and secondary endpoints described and relevant to the question? Yes
  7.2. Were nutrition measures appropriate to question and outcomes of concern? Yes
  7.3. Was the period of follow-up long enough for important outcome(s) to occur? Yes
  7.4. Were the observations and measurements based on standard, valid, and reliable data collection instruments/tests/procedures? Yes
  7.5. Was the measurement of effect at an appropriate level of precision? Yes
  7.6. Were other factors accounted for (measured) that could affect outcomes? Yes
  7.7. Were the measurements conducted consistently across groups? Yes
8. Was the statistical analysis appropriate for the study design and type of outcome indicators? Yes
  8.1. Were statistical analyses adequately described and the results reported appropriately? Yes
  8.2. Were correct statistical tests used and assumptions of test not violated? Yes
  8.3. Were statistics reported with levels of significance and/or confidence intervals? Yes
  8.4. Was "intent to treat" analysis of outcomes done (and as appropriate, was there an analysis of outcomes for those maximally exposed or a dose-response analysis)? N/A
  8.5. Were adequate adjustments made for effects of confounding factors that might have affected the outcomes (e.g., multivariate analyses)? N/A
  8.6. Was clinical significance as well as statistical significance reported? N/A
  8.7. If negative findings, was a power calculation reported to address type 2 error? N/A
9. Are conclusions supported by results with biases and limitations taken into consideration? Yes
  9.1. Is there a discussion of findings? Yes
  9.2. Are biases and study limitations identified and discussed? Yes
10. Is bias due to study's funding or sponsorship unlikely? Yes
  10.1. Were sources of funding and investigators' affiliations described? Yes
  10.2. Was the study free from apparent conflict of interest? Yes