NAP: Energy Balance and Body Composition (2007)
Citation:
Can F, Yilmaz I, Erden Z. Morphological characteristics and performance variables of women soccer players. J Strength Cond Res. 2004; 18(3): 480-485.
Study Design:
Case-control study
Class:
C - Click here for explanation of classification scheme.
Quality Rating:

Research Purpose:
To describe morphological characteristics of women soccer players and to determine the effect of soccer training on their performance variables in comparison with sedentary women.
Inclusion Criteria:
- Female athletes who play soccer in one of the top-class Turkish soccer teams with at least three years of active participation in professional soccer
- Sedentary women who were students at Hacettepe University School of Physical Therapy who had never actively participated in regular sports or such a sportive training.
Exclusion Criteria:
Excluded if not included above.
Description of Study Protocol:
Recruitment
- Experimental: Female members of Turkish professional soccer teams
- Control: Female physical therapy students at Hacettepe University School of Physical Therapy.
Design
Case-control study.
Blinding Used
All measurements taken by same physical therapist.
Statistical Analysis
Students T-test for comparisons between groups, significance set at P≤0.05.
Data Collection Summary:
Timing of Measurements
Measurements taken in both groups and compared.
Dependent Variables
- Circumference measures around biceps, relaxed arm, forearm, thigh, calf, chest and abdomen with a constant tension steel tape
- Diameters taken for biacromial, biiliac, bitrochanteric, wrist, elbow, knee and ankle sites
- Skinfold sites were biceps, triceps, subscapular, chest, midaxillar, abdominal, suprailiac, anterior thigh, medial calf; all taken on right side of body with Lange skinfold caliper
- Sit-and-reach test for low back and hamstring flexibility
- Four-level squat thrust agility test in 10 seconds for agility
- Sargent Vertical Jump and standing broad jump for anaerobic power and leg muscle power, respectively
- Dynamic pulmonary functions measured by vitalograph spirometer (FEV1, FVC).
Description of Actual Data Sample:
- Initial N: 17 for experimental; 17 for controls
- Attrition (final N): 17 for experimental; 17 for controls.
Age
- Experimental: 20.73±2.09 years
- Control: 21.47±1.06 years.
Ethnicity
Not reported.
Other Relevant Demographics
All subjects from Turkey.
Location
Ankara, Turkey.
Summary of Results:
Athletes | Non-athletes | |||
Mean | SD | Mean | SD | |
Age (years) | 20.73 | 2.09 | 21.47 | 1.06 |
Weight (kg) | 56.63 | 5.03 | 52.80 | 6.49 |
Chest Circumference (cm) | 85.10 | 3.43 | 82.10 | 3.95 |
Abdomen Circumference (cm) | 74.57* | 3.14 | 72.23 | 6.38 |
Thigh Circumference (cm) | 51.07* | 2.87 | 3.12 | 2.26 |
Biacromial Diameter (cm) | 35.27* | 1.95 | 34.97 | 2.91 |
Biiliac diameter (cm) | 27.93 | 1.97 | 28.77 | 1.75 |
Knee Diameter (cm) | 8.91* | 0.77 | 8.17 | 0.65 |
Ankle Diameter (cm) | 6.42* | 0.51 | 6.03 | 0.42 |
Percentage body fat | 19.75* | 0.69 | 22.63 | 0.50 |
Absolute body fat (kg) | 10.87 | 2.62 | 12.17 | 2.68 |
Lean body weight (kg) | 45.66* | 3.66 | 40.63 | 3.91 |
Endomorphy | 3.07* | 0.80 | 3.57 | 0.95 |
Mesomorphy | 3.55 | 0.89 | 3.35 | 1.33 |
Ectomorphy | 2.43 | 0.96 | 2.90 | 0.97 |
Trunk Extension flexibility (cm) | 28.33* | 7.24 | 20.57 | 7.32 |
Sit and Reach Test (cm) | 12.23 | 8.94 | 9.00 | 7.63 |
Squat thrust (reps in 10 seconds) | 6.28* | 0.66 | 4.48 | 0.52 |
Vertical jump (cm) | 34.48* | 7.11 | 25.77 | 6.51 |
Standing broad jump (cm) | 192.48* | 15.60 | 152.20 | 21.55 |
Anaerobic power (kg/s) | 73.08* | 10.93 | 59.05 | 11.22 |
FEV 1 (percentage) | 90.53 | 9.52 | 95.75 | 6.80 |
FVC (percentage) | 90.93 | 8.02 | 94.25 | 5.44 |
FEV 1/FVC (percentage) | 88.07 | 3.84 | 87.50 | 8.29 |
PEF (percentage) | 104.33 | 12.71 | 107.67 | 13.85 |
Author Conclusion:
- Female soccer players are less endomorphic than sedentary women
- Anaerobic power, leg power and agility were higher in athletes than in non-athletes
- No significant differences in flexibility or pulmonary functions
- Regular training may generally increase the mesomorphic component and decrease the endomorphic component by increasing the level of performance.
Funding Source:
University/Hospital: | Hacettepe University School of Physical Therapy (Turkey) |
Reviewer Comments:
- No information on blinding by data collectors, but all data collected by same physical therapist
- No information provided on demographics or other relevant health information
- No information on study funding source provided.
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) | N/A | |
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) | N/A | |
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? | N/A | |
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? | Yes | |
3.1. | Was the method of assigning subjects/patients to groups described and unbiased? (Method of randomization identified if RCT) | Yes | |
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.) | 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.) | ??? | |
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? | ??? | |
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? | N/A | |
6.1. | In RCT or other intervention trial, were protocols described for all regimens studied? | N/A | |
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? | N/A | |
6.4. | Was the amount of exposure and, if relevant, subject/patient compliance measured? | N/A | |
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? | N/A | |
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? | N/A | |
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? | Yes | |
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? | ??? | |
10.1. | Were sources of funding and investigators' affiliations described? | No | |
10.2. | Was the study free from apparent conflict of interest? | ??? | |