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: 11531040Study Design:
Non-Randomized Controlled Trial
Class:
C - Click here for explanation of classification scheme.
Quality Rating:
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:
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Body Weight (kg)
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Height (cm)
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Body Fat Percentage
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BMI (kg/m2)
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FFM (kg)
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T1
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75.1±2.6
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172.9±1.5
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17.3±2.1
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24.9±1.2
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62.1±2.2
|
|
T2
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71.5±1.3*
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16.8±1.4
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23.1±0.7*
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59.8±2.7
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Percentage Change
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-4.9±1.2
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-1.8±1.8
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-6.8±1.1
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-3.7±2.1
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|
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Energy Intake (kcal per Day)
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Total Protein (g per Day)
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Total Fat (g per Day)
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Total CHO (g per Day)
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T1
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3,029±281.6
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124.9±16.2
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118.2±9.9
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360.7±52.2
|
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T2
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2,101.7±179.4*
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88.3±8.5*
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85.7±8.5*
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236.5±25.1
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Triglycerides (mmol per L)
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FFA (mmol per L)
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LDL-C (mmol per L)
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HDL-C (mmol per L)
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T1
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0.63±0.06
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0.31±0.05
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2.57±0.2
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1.15±0.05
|
|
T2
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0.92±0.08
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0.53±0.2
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2.62±0.2
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1.09±0.08
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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.
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Quality Criteria Checklist: Primary Research
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| 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 | |