STUDY DESIGN: Cross-sectional study.OBJECTIVES: This study: (1) investigated the accuracy of bioelectrical impedance analysis (BIA) and skinfold thickness relative to dual-energy X-ray absorptiometry (DXA) in the assessment of body composition in people with spinal cord injury (SCI), and whether sex and lesion characteristics affect the accuracy, (2) developed new prediction equations to estimate fat free mass (FFM) and percentage fat mass (FM%) in a general SCI population using BIA and skinfolds outcomes.SETTING: University, the Netherlands.METHODS: Fifty participants with SCI (19 females; median time since injury: 15 years) were tested by DXA, single-frequency BIA (SF-BIA), segmental multi-frequency BIA (segmental MF-BIA), and anthropometry (height, body mass, calf circumference, and skinfold thickness) during a visit. Personal and lesion characteristics were registered.RESULTS: Compared to DXA, SF-BIA showed the smallest mean difference in estimating FM%, but with large limits of agreement (mean difference = -2.2%; limits of agreement: -12.8 to 8.3%). BIA and skinfold thickness tended to show a better estimation of FM% in females, participants with tetraplegia, or with motor incomplete injury. New equations for predicting FFM and FM% were developed with good explained variances (FFM: R2 = 0.94; FM%: R2 = 0.66).CONCLUSIONS: None of the measurement techniques accurately estimated FM% because of the wide individual variation and, therefore, should be used with caution. The accuracy of the techniques differed in different subgroups. The newly developed equations for predicting FFM and FM% should be cross-validated in future studies.
Background: The environment affects children’s energy balance-related behaviors to a considerable extent. A context-based physical activity and nutrition school- and family-based intervention, named KEIGAAF, is being implemented in low socio-economic neighborhoods in Eindhoven, The Netherlands. The aim of this study was to investigate: 1) the effectiveness of the KEIGAAF intervention on BMI z-score, waist circumference, physical activity, sedentary behavior, nutrition behavior, and physical fitness of primary school children, and 2) the process related to the implementation of the intervention. Methods: A quasi-experimental, controlled study with eight intervention schools and three control schools was conducted. The KEIGAAF intervention consists of a combined top-down and bottom-up school intervention: a steering committee developed the general KEIGAAF principles (top-down), and in accordance with these principles, KEIGAAF working groups subsequently develop and implement the intervention in their local context (bottom-up). Parents are also invited to participate in a family-based parenting program, i.e., Triple P Lifestyle. Children aged 7 to 10 years old (grades 4 to 6 in the Netherlands) are included in the study. Effect evaluation data is collected at baseline, after one year, and after two years by using a child questionnaire, accelerometers, anthropometry, a physical fitness test, and a parent questionnaire. A mixed methods approach is applied for the process evaluation: quantitative (checklists, questionnaires) and qualitative methods (observations, interviews) are used. To analyze intervention effectiveness, multilevel regression analyses will be conducted. Content analyses will be conducted on the qualitative process data. Discussion: Two important environmental settings, the school environment and the family environment, are simultaneously targeted in the KEIGAAF intervention. The combined top-down and bottom-up approach is expected to make the intervention an effective and sustainable version of the Health Promoting Schools framework. An elaborate process evaluation will be conducted alongside an effect evaluation in which multiple data collection sources (both qualitative and quantitative) are used.
In their developmental model, Stodden et al. (2008) propose age-dependent relations between motor competence, physical activity,perceived motor competence, physical fitness, and weight status thatcan lead to a spiral of (dis)engagement. The goal of this study was toexplore these relations in a large sample of Dutch primary schoolchildren. To our knowledge, this is the first study including all fiveaspects of the model and a large sample of children between four andthirteen years old. Cross-sectional data was collected in 2068 children(ages 4–13), divided over 9 age groups. During physical educationclasses, they completed the 4-Skills Test, a physical activity question-naire, versions of the Self-Perception Profile for Children, Eurofit testand anthropometry measurements. Correlation coefficients per agegroup were calculated (full information maximum likelihood) andtransformed using a Fisher’s r to z transformation, after which thetest-statistic z was calculated. The results show that all five factors arerelated to each other and that a tipping point exists at which relationsemerge or strengthen. Physical fitness is related to motor competenceand physical activity and these relationships strengthen with age. Arelationship between BMI and the other four factors emerges in middlechildhood. Although the model described that physical activity stimu-lates motor competence in early childhood, our data showed that at ayoung age, both motor competence and perceived motor competencehad no relation with physical activity, while they were weakly related toeach other. In middle childhood, both motor competence and perceivedmotor competence were related to physical activity. Our findingsdemonstrate that children in late childhood who have higher perceivedmotor competence are also more physically active, have higher physicalfitness, higher motor competence and lower BMI. Our results indicatethat targeting motor competence at a young age might be a feasible wayto ensure continued participation in physical activities throughoutchildhood and adolescence. Funding source: Netherlands Organization for Scientific Research.
