NAP: Energy Balance and Body Composition (2007)

Citation:

Filaire E, Maso F, Degoutte F, Jouanel P, Lac G. Food restriction, performance, psychological state and lipid values in judo athletes. Int J Sports Med. 2001; 22: 454-459. 

PubMed ID: 11531040
 
Study Design:
Non-Randomized Controlled Trial
Class:
C - Click here for explanation of classification scheme.
Quality Rating:
Neutral NEUTRAL: See Quality Criteria Checklist below.
Research Purpose:
To investigate the influence of a seven-day food restriction on physical performance, plasma lipids, lipoproteins and apolipoproteins and psychological profile in a group of elite male judo athletes preparing for a national championship.
Inclusion Criteria:
  • Participation in six to nine hours per week of judo training
  • Competitive experience in regional and national tournaments
  • Competing in a category under 73kg.
Exclusion Criteria:
  • Use of drugs or medications
  • History of endocrine disorders before or during the study
  • Use of dietary supplements.
Description of Study Protocol:
  • Recruitment: Members of the Auvergne League Judo Team
  • Design: Non-randomized clinical trial
  • Intervention: A seven-day low-dietary energy restriction period
  • Statistical Analysis: Wilcoxon's test for within-procedure differences (baseline vs. follow-up). Alpha set at 0.05.

 

Data Collection Summary:

Timing of Measurements

  • Two months and one day prior to a major national judo competition (T1)
  • After a seven-day energy restriction period (T2).

 Dependent Variables

  • Physical performance (muscular grip strength measures, vertical jump, successive maximal jump test)
  • Biochemical measures (apolipoproteins, lipoproteins, glycerides, etc.)
  • Psychological measurements; Profile of Mood States (POMS) survey.

Independent Variables

  • Seven-day energy restriction
  • Dietary data collected using a seven-day food record.
Description of Actual Data Sample:
  • Initial N: 11 males
  • Attrition (final N): 11
  • Age: Not specified
  • Ethnicity: Not specified
  • Other relevant demographics: Minimum of 10±3.2 years of judo practice (mean±SD)
  • Anthropometrics: See Results section
  • Location: Aubiere, France.
Summary of Results:

 
Body Weight (kg)
Height (cm)
Body Fat Percentage
BMI (kg/m2)
FFM (kg)
T1
75.1±2.6
172.9±1.5
17.3±2.1
24.9±1.2
62.1±2.2
T2
71.5±1.3*
 
16.8±1.4
23.1±0.7*
59.8±2.7
Percentage Change
-4.9±1.2
 
-1.8±1.8
-6.8±1.1
-3.7±2.1

 
Energy Intake (kcal per Day)
Total Protein (g per Day)
Total Fat (g per Day)
Total CHO (g per Day)
T1
3,029±281.6
124.9±16.2
118.2±9.9
360.7±52.2
T2
2,101.7±179.4*
88.3±8.5*
85.7±8.5*
236.5±25.1

 

 
Triglycerides (mmol per L)
FFA (mmol per L)
LDL-C (mmol per L)
HDL-C (mmol per L)
T1
0.63±0.06
0.31±0.05
2.57±0.2
1.15±0.05
T2
0.92±0.08
0.53±0.2
2.62±0.2
1.09±0.08

 

Other Findings

  • Nutrient analysis indicated that the athletes followed a low carbohydrate diet whatever period of the investigation and had mean micronutrient intakes below French recommendations.
  • Significant decrease in left hand grip test values (T2<T1, P<0.05)
  • Significant increases in Tension, Anger, Fatigue, and Confusion (T2>T1, P<0.05)
  • Significant decrease in Vigor (T1>T2, P<0.05)
  • Data presented as mean±SD.
Author Conclusion:
The data indicate that a seven-day food restriction adversely affects the physiology and psychology of judo athletes and impairs physical performance, possibly due to inadequate intake of carbohydrates and micronutrients.
Funding Source:
University/Hospital: UFR-STAPS, Universiate Blaise Pascal (France)
Reviewer Comments:
  • Not blinded, no control group
  • Exact method of decreasing dietary intake was not specified; article only states that there was an energy restriction
  • Without any kind of control, it is unknown whether the changes reported are due to the decreased dietary regimen or due to training or because the competition was drawing closer. 
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? ???
  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? No
  2.4. Were the subjects/patients a representative sample of the relevant population? ???
3. Were study groups comparable? N/A
  3.1. Was the method of assigning subjects/patients to groups described and unbiased? (Method of randomization identified if RCT) N/A
  3.2. Were distribution of disease status, prognostic factors, and other factors (e.g., demographics) similar across study groups at baseline? N/A
  3.3. Were concurrent controls or comparisons used? (Concurrent preferred over historical control or comparison groups.) N/A
  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? N/A
  5.1. In intervention study, were subjects, clinicians/practitioners, and investigators blinded to treatment group, as appropriate? N/A
  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.) N/A
  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? No
  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? ???
  6.5. Were co-interventions (e.g., ancillary treatments, other therapies) described? ???
  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)? Yes
  8.5. Were adequate adjustments made for effects of confounding factors that might have affected the outcomes (e.g., multivariate analyses)? Yes
  8.6. Was clinical significance as well as statistical significance reported? Yes
  8.7. If negative findings, was a power calculation reported to address type 2 error? No
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? No
  10.2. Was the study free from apparent conflict of interest? Yes