Pediatrics and Physical Activity

Study Design:
- Click here for explanation of classification scheme.
Quality Rating:
Research Purpose:

To test hypothesis that participation in a physical fitness program would have a positive impact on health-related fitness and blood lipid levels in low-fit children.

Inclusion Criteria:

Children recruited from a pool of students identified by their physical education teachers as having failed to meet at least three of the four (body fat, one-mile walk/run, sit-and-reach, sit-ups) Physical Best fitness standards.

Exclusion Criteria:

None specified.

Description of Study Protocol:
  • The after-school fitness program was conducted one hour per day, three days per week for 10 weeks in a gymnasium with access to outdoor facilities
  • The program focused on primarily aerobic activities and consisted of a variety of games and activities such as running games, water aerobics, step aerobics, circuit activities and team-oriented activities
  • Muscular strength and endurance-promoting activities were also incorporated into the activities
  • Three upper-level, undergraduate physical education major students planned the activities and participated with the children to provide encouragement and motivation
  • Control group represented those children who could not regularly attend the program due to scheduling conflicts or transportation problems.

Statistical Analysis

Multivariate analysis of variance (MANOVA) and dependent T-tests: To determine whether changes occurred from pre- to post-test in the treatment and control groups.

Data Collection Summary:
  • Dependent variables:
    • Body fatness: Expressed as a sum of skinfold thickness measures at six sites including triceps, subscapular, abdominal, thigh, ilium and medial calf
    • Height and Weight: Measured
    • Field Test Procedures: Cardiorespiratory endurance - one-mile walk/run, Muscular endurance – timed sit-ups, Flexibility – sit-and-reach
    • Exercise testing (measured HR, oxygen uptake and maximal oxygen uptake (VO2max);
    • Blood analysis (TC, TG, HDL-C and LDL-C).
  • Independent variables: Treatment or control group (see study protocol above)
  • Control variables: None.
Description of Actual Data Sample:
  • Original sample: 28 children – 18 children (eight girls, 10 boys) volunteered to be program participants and 10 children (four girls, six boys) served as the control group.
  • Withdrawals/Drop-outs: One child in the control group did not complete the field testing and was not included in that part of the analysis. Two children in treatment group and one child in control group were unable to complete all three phases of the treadmill test and were therefore not included in this part of the data analysis. Six children in treatment group and three children in control group were apprehensive about having their blood drawn and therefore not included in this part of the analysis.
  • Final sample: 28 children – 18 treatment children (eight girls, 10 boys) and 10 controls (four girls, six boys) for the anthropometry analysis; 18 treatment and nine controls for field test performance; 16 treatments and nine controls for cardiorespiratory responds and 12 treatments and seven controls for the blood lipid data.
  • Location: Muncie, Indiana
  • Race/Ethnicity: Not specified
  • SES: Not specified
  • Age: Eight to 11 years old.
Summary of Results:


  • Using percent norms for the sum of two skinfolds reported in the National Children and Youth Fitness Survey I (NCYFS) and NCYFS II, 67% of the children in the treatment group and 70% of the control group participants were at or below the 25th percentile. This info indicated that the goal of targeting low-fit children was achieved.
  • A dependent T-test revealed that there was a significant increase from pre- to post-test in height (P<0.05) and in weight (P<0.05), but not for sum of skinfolds
  • The Physical Best standard for body fatness was achieved by 16.6% of the program participants and 22.2% of the control group on both the pre- and post-test.

Field Testing

  • No significant difference between groups with respect to each field test variable at the beginning of the program were noted
  • The treatment group performed significant better on the sit-and-reach test after 10-week program (P<0.05)
  • No significant changes occurred in the control group
  • For the treatment group, there was a significant decrease (11%) in one-mile walk/run time (P<0.05) and significant increase in sit-and-reach (P<0.05) and sit-up performances (P<0.05).

Physical Best Standard

No children achieved the Physical Best standard on either test.

Laboratory Testing

  • Both groups improved from pre- to post-test. Dependent T-tests showed heart rate decreased over time at three miles per hour (mph) and at 4.5 mph.
  • Oxygen uptake also decreased over time at three mph and at 4.5 mph.

Concentrations of TC, TG, HDL-C and LDL-C

  • No differences between groups on the pretest with respect to any of these variables
  • On the post-test, TG level was sig. higher in the control group compared to the treatment group (P<0.05).
Author Conclusion:
  • In general, the program appeared to have a positive impact on the field-test measures, but failed to improved body fatness, cardiovascular responses to submaximal and maximal exercise and blood lipid profiles
  • The fitness program may not have provided enough physical activity beyond what the children normally received to stimulate change in submaximal heart rate or VO2 max.
Funding Source:
Campbell-Taggart Inc.
Food Company:
Reviewer Comments:


  • Unclear if this study should be defined as treatment or prevention trial, as not all subjects were necessarily overweight. Unfit children were identified as opposed to overweight children.
  • If it is trial is defined as a prevention trial then it does not meet our inclusion criteria, based on the sample size and intervention duration
  • Unclearly, if the treatment subjects and control subjects’ baseline sum of the two skinfolds were equal (67% vs. 70% at or below the 25th percentile).
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? 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? Yes
  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? N/A
  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? Yes
  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? Yes
  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? 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? No
  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? ???
  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? No
  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? No
  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? No
  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)? No
  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? Yes
  10.2. Was the study free from apparent conflict of interest? Yes