Cross-validation of bioelectrical impedance analysis for the assessment of body composition in a representative sample of 6- to 13-year-old children

Relationship of physical activity with motor skills, aerobic fitness and body fat in preschool children: a cross-sectional and longitudinal study (Ballabeina)

BACKGROUND

Adiposity, low aerobic fitness and low levels of activity are all associated with clustered cardiovascular disease risk in children and their high prevalence represents a major public health concern.

OBJECTIVE

The aim of this study is to investigate the relationship of objectively measured physical activity (PA) with motor skills (agility and balance), aerobic fitness and %body fat in young children.

DESIGN

This study is a cross-sectional and longitudinal analyses using mixed linear models. Longitudinal data were adjusted for baseline outcome parameters.

SUBJECTS

In all, 217 healthy preschool children (age 4-6 years, 48% boys) participated in this study.

MEASUREMENTS

PA (accelerometers), agility (obstacle course), dynamic balance (balance beam), aerobic fitness (20-m shuttle run) and %body fat (bioelectric impedance) at baseline and 9 months later.

RESULTS

PA was positively associated with both motor skills and aerobic fitness at baseline as well as with their longitudinal changes. Specifically, only vigorous, but not total or moderate PA, was related to changes in aerobic fitness. Higher PA was associated with less %body fat at baseline, but not with its change. Conversely, baseline motor skills, aerobic fitness or %body fat were not related to changes in PA.

CONCLUSION

In young children, baseline PA was associated with improvements in motor skills and in aerobic fitness, an important determinant of cardiovascular risk.

Health-related fitness in children and adolescents

PURPOSE

The American Physical Therapy Association Section on Pediatrics developed a task force to summarize fitness guidelines for children and adolescents. The purposes of this article were to review components, measurement methods, and consequences of physical fitness, and to summarize evidence-based activity recommendations for youth.

SUMMARY OF KEY POINTS

Health-related fitness is comprised of body composition, flexibility, cardiorespiratory endurance, and muscular strength and endurance. Each of these components is reviewed in terms of definition, assessment, normative values, and recommendations.

CONCLUSIONS

The task force supports the guidelines of the US Department of Health and Human Services, which state that to promote overall health and wellness, youth should participate in 60 minutes or more of physical activity every day.

RECOMMENDATIONS FOR CLINICAL PRACTICE

Physical therapists should apply research relevant to health-related fitness when treating youth. Promoting fitness, health, and wellness in our communities is a responsibility all therapists should assume.

Independent contribution of parental migrant status and educational level to adiposity and eating habits in preschool children

BACKGROUND/OBJECTIVE

Little is known about the precise role of parental migrant status (MS) and educational level (EL) on adiposity and various eating habits in young children. Therefore, we assessed their independent contribution in preschoolers.

SUBJECTS/METHODS

Of 655 randomly selected preschoolers, 542 (5.1±0.6 years; 71% of parental MS and 37% of low parental EL) were analysed. Body composition was measured by bioelectrical impedance. Eating habits were assessed using a semiqualitative food frequency questionnaire and analysed according to five messages developed by the Swiss Society for Nutrition, based on factors implicated in childhood obesity: (1) 'Drinking water and decreasing sweetened drinks', (2) 'Eating fruit and vegetables', (3) 'Decreasing breakfast skipping', (4) 'Reducing fatty and sweet foods' and (5) 'Reducing the intake of meals and snacks in front of television'.

RESULTS

Children of migrant and low EL parents had higher body fat, ate more meals and snacks while watching television and had more fruit and fatty foods compared with their respective counterparts (all P≤ 0.04). Children of low EL parents also consumed less water and vegetables compared with their counterparts (all P≤ 0.04). In most instances, we found an independent contribution of parental MS and EL to adiposity and eating habits. A more pronounced effect was found if both parents were migrants or of low EL. Differences in adiposity and eating habits were relatively similar to the joint parental data when assessed individually for maternal and paternal MS and EL.

CONCLUSIONS

Parental MS and EL are independently related to adiposity and various eating habits in preschoolers.

Relative importance of body composition, osteoporosis-related behaviors, and parental income on bone speed of sound in adolescent females

INTRODUCTION

Adolescence provides a unique opportunity to employ strategies aimed at optimizing peak bone mass yet there are limited studies on the relationship between specific social constructs, osteoporosis-related behaviors, and bone health status in adolescent females. The purpose of this study was to examine associations between bone speed of sound (SOS) and body composition, osteoporosis-related health behaviors, and parental income in adolescent females.

METHODS

Four hundred forty-two female students in grades 9-12 from schools in Southern Ontario, Canada were measured for height, body mass, and percent body fat and completed a battery of instruments to assess osteoporosis-related health behaviors. Bone SOS was measured by transaxial quantitative ultrasound at the distal radius and midtibia.

RESULTS

Percent body fat was a negative correlate of tibial SOS. No significant correlation was found between physical activity and bone SOS yet physical activity was negatively related to adiposity. Hierarchical regression showed that age and percent body fat were the most important predictors of the variance in tibial SOS scores, with calcium intake having a weaker, yet significant, relationship. Age was the only statistically significant predictor of radial SOS. Users of oral contraceptives had higher radial SOS when controlling for age. Higher parental income was not associated with bone SOS but positive associations between parental income, daily calcium intake, and weekly physical activity were noted.

CONCLUSIONS

Bone SOS is reduced in adolescent females with increased adiposity, whereas it is positively influenced by oral contraceptives and daily calcium intake.

Influence of a lifestyle intervention in preschool children on physiological and psychological parameters (Ballabeina): study design of a cluster randomized controlled trial

BACKGROUND

Childhood obesity and physical inactivity are increasing dramatically worldwide. Children of low socioeconomic status and/or children of migrant background are especially at risk. In general, the overall effectiveness of school-based programs on health-related outcomes has been disappointing. A special gap exists for younger children and in high risk groups.

METHODS/DESIGN

This paper describes the rationale, design, curriculum, and evaluation of a multicenter preschool randomized intervention study conducted in areas with a high migrant population in two out of 26 Swiss cantons. Twenty preschool classes in the German (canton St. Gallen) and another 20 in the French (canton Vaud) part of Switzerland were separately selected and randomized to an intervention and a control arm by the use of opaque envelopes. The multidisciplinary lifestyle intervention aimed to increase physical activity and sleep duration, to reinforce healthy nutrition and eating behaviour, and to reduce media use. According to the ecological model, it included children, their parents and the teachers. The regular teachers performed the majority of the intervention and were supported by a local health promoter. The intervention included physical activity lessons, adaptation of the built infrastructure; promotion of regional extracurricular physical activity; playful lessons about nutrition, media use and sleep, funny homework cards and information materials for teachers and parents. It lasted one school year. Baseline and post-intervention evaluations were performed in both arms. Primary outcome measures included BMI and aerobic fitness (20 m shuttle run test). Secondary outcomes included total (skinfolds, bioelectrical impedance) and central (waist circumference) body fat, motor abilities (obstacle course, static and dynamic balance), physical activity and sleep duration (accelerometry and questionnaires), nutritional behaviour and food intake, media use, quality of life and signs of hyperactivity (questionnaires), attention and spatial working memory ability (two validated tests). Researchers were blinded to group allocation.

DISCUSSION

The purpose of this paper is to outline the design of a school-based multicenter cluster randomized, controlled trial aiming to reduce body mass index and to increase aerobic fitness in preschool children in culturally different parts of Switzerland with a high migrant population.

TRIAL REGISTRATION

Trial Registration: (clinicaltrials.gov) NCT00674544.