Conquering Childhood Inactivity: Is the Answer in the Past?

Comparison of physical activity and physical fitness in children and adolescents of Chinese Han and Tibet ethnicity

Background

Physical activity (PA) and physical fitness (PF) are important markers of health status in children and adolescents in different ethnicities. In this study, we aimed to compare the PA and PF indicators between Tibetan and Han children and adolescents.

Methods

Children and adolescents of 4-9 grades were recruited in Shigatse (n = 963) and Shanghai (n = 2,525) respectively. The information related to demographic, PA, and PF was collected via a self-reported questionnaire. PA was assessed through the participation of moderate to vigorous PA (MVPA), muscle-strengthening exercise (MSE) and organized sport participation (OSP). PF was estimated using the International Fitness Scale containing components of overall fitness, cardiorespiratory fitness, speed and agility, muscular strength and flexibility.

Results

Han (mean age = 13.45 ± 3.3 years; 49.7% girls) and Tibet (mean age = 13.8 ± 2.5 years; 48.3% girls) children and adolescents from Shanghai and Shigatse completed the questionnaire survey. It was revealed that Tibetan students had higher MVPA, MSE and OSP than children and adolescents of Han ethnicity (p < 0.01, small to medium effect size). A relatively higher percentage of student in Shanghai did not participate in any form of PA. On the other hand, less Tibetan students thought their PF indicators including overall fitness, cardiorespiratory fitness, speed and agility, muscular strength and flexibility were poor or very poor than their counterparts of Han ethnicity (p < 0.01, small to medium effect size).

Conclusion

Tibetan children and adolescents have higher levels of PA and PF in comparison to their Han counterparts. More children and adolescents of Han ethnicity engage in no PA and think their PF indicators were poor.

Recent Secular Trends in Child and Adolescent Physical Activity and Sedentary Behavior Internationally: Analyses of Active Healthy Kids Global Alliance Global Matrices 1.0 to 4.0

Background: We examined recent global secular trends in 5 indicators of child and adolescent physical activity and sedentary behavior (Overall Physical Activity, Organized Sport and Physical Activity, Active Play, Active Transportation, and Sedentary Behavior) and 4 influences on these (Family and Peers, School, Community and Environment, and Government). Methods: Active Healthy Kids Global Alliance letter grades (A+ to F) were assigned numbers from 15 to 2, with 0 assigned for missing/incomplete grades. Trends from Active Healthy Kids Global Alliance Global Matrices 1.0 (2014) to 4.0 (2022) were analyzed using linear mixed-effects models with level of economic development and gender inequity considered as potential moderators. Results: Report card grades were generally relatively stable. Trends generally did not differ significantly by level of economic development (except for Active Transportation and Active Play), but gender inequality did significantly moderate trends for most of the indicators, with higher gender inequality associated with more adverse changes in grades. The number of “incomplete” grades decreased over time, but this did not reach statistical significance. Conclusions: While trends varied within and between countries, physical activity and sedentary behaviors, and the influences on these behaviors globally, were relatively stable over the past decade or so, albeit at undesirable levels.

Caring for the Amish: What Every Anesthesiologist Should Know

The Amish are a relatively isolated group with cultural and religious customs that differ significantly from the mainstream American population. Functioning as tight-knit communities with strong conservative Christian beliefs, the Amish maintain a culture based on intentional separateness from the outside world. Key aspects of Amish life include distinct clothing and behaviors, a unique language, an agrarian lifestyle, limited formal education, nonviolence/nonaggression, and a general lack of modern technology, as exemplified by the use of the traditional horse-and-buggy. The Amish have distinct health care practices, beliefs, and goals, and because of differing genetics and lifestyle, also have a distinct constellation of health and disease characteristics. This article reviews the core beliefs, community and lifestyle, health care beliefs and practices, and health characteristics of this unique and medically challenging population. Generalizable strategies for providing culturally competent care for any such ethnically, socially, or medically unique community are presented.

Physical Activity and Sedentary Screen Time in Obese and Overweight Children Living in Different Environments

AIM

To assess the relationship of children's physical activity and sedentary screen time with overweight and obesity in children living in different environments (town and city) in Lithuania.

METHODS

An analysis of anthropometric data from 532 children living in town and city areas was performed. A youth physical activity questionnaire (YPAQ) was conducted to evaluate physical activity and sedentary screen time.

RESULTS

The prevalence of overweight and obesity among the children was 25.5% in the town and 18.6% in the city. Children living in the town on average engaged 9.3 min/day less in moderate to vigorous physical activity (p=0.050) and had 33.2 MET-min/day lower energy expenditure than children living in the city. Sedentary screen time was extremely high on weekends in both town and city children.

CONCLUSIONS

A higher prevalence of overweight and obesity and a lower amount of moderate-to-vigorous physical activity was found in children living in the town compared to children living in the city.

Age as a moderator of the secular trend for grip strength in Canada and the United States

PURPOSE

To determine whether grip strength changed on average over recent decades at each of two age levels (children and adolescents versus adults) in Canada and the US.

METHODS

For each sex, weighted least squares regression analyses were performed on mean grip strength values as reported in studies conducted from the 1960s onwards.

RESULTS

Grip strength did not change significantly as a function of year tested in children and adolescents, whereas it declined as a negatively accelerated function of year tested in adults.

CONCLUSION

The results are contrary to what might be expected given that body weight has increased in both countries in recent decades and given that grip strength has been found to be positively correlated with body weight. It is suggested that there was a concurrent change in a factor that operated to counteract the effect of increased body weight on grip strength, a prime candidate being a decrease in levels of serum vitamin D. It is also suggested that the secular decline in adult grip strength can be explained by a factor that affects muscular function but which has a long latency period, a prime candidate here being obesity history.

Quality control methods in accelerometer data processing: identifying extreme counts

BACKGROUND

Accelerometers are designed to measure plausible human activity, however extremely high count values (EHCV) have been recorded in large-scale studies. Using population data, we develop methodological principles for establishing an EHCV threshold, propose a threshold to define EHCV in the ActiGraph GT1M, determine occurrences of EHCV in a large-scale study, identify device-specific error values, and investigate the influence of varying EHCV thresholds on daily vigorous PA (VPA).

METHODS

We estimated quantiles to analyse the distribution of all accelerometer positive count values obtained from 9005 seven-year old children participating in the UK Millennium Cohort Study. A threshold to identify EHCV was derived by differentiating the quantile function. Data were screened for device-specific error count values and EHCV, and a sensitivity analysis conducted to compare daily VPA estimates using three approaches to accounting for EHCV.

RESULTS

Using our proposed threshold of ≥ 11,715 counts/minute to identify EHCV, we found that only 0.7% of all non-zero counts measured in MCS children were EHCV; in 99.7% of these children, EHCV comprised < 1% of total non-zero counts. Only 11 MCS children (0.12% of sample) returned accelerometers that contained negative counts; out of 237 such values, 211 counts were equal to -32,768 in one child. The medians of daily minutes spent in VPA obtained without excluding EHCV, and when using a higher threshold (≥19,442 counts/minute) were, respectively, 6.2% and 4.6% higher than when using our threshold (6.5 minutes; p<0.0001).

CONCLUSIONS

Quality control processes should be undertaken during accelerometer fieldwork and prior to analysing data to identify monitors recording error values and EHCV. The proposed threshold will improve the validity of VPA estimates in children's studies using the ActiGraph GT1M by ensuring only plausible data are analysed. These methods can be applied to define appropriate EHCV thresholds for different accelerometer models.

Correlates of physical activity and inactivity in urban Mexican youth

OBJECTIVES

To evaluate correlates of physical activity in Mexico City school youth.

METHODS

A cross-sectional survey was conducted with 1,004 school youth (490 males and 514 females), 9-18 years of age resident in Mexico City. Age, height, body mass index (BMI), socioeconomic status (SES), time viewing television and playing video games (physical inactivity), and perceived sport/physical activity status of mother and father were evaluated as potential correlates of physical activity [Physical Activity Questionnaire (PAQ)]. Multiple linear regression analyses (backward elimination) by age group and sex were used.

RESULTS

Physical activity declined in older adolescents, while differences between the two younger age groups were minimal. Television time showed a similar tendency. Overall, fathers were perceived as being active in sport/physical activity more frequently than mothers. Significant predictors of activity differed by age group and sex. For the total sample, age (negative) and perceived sport/activity status of the mother (positive) were significant predictors of the PAQ in boys, and age and the BMI (negative) and height and perceived sport/activity status of both parents (positive) were significant predictors for girls. Age (negative) was the main predictor for inactivity in both males and females.

CONCLUSIONS

Potential correlates of physical activity and inactivity considered in this analysis were limited and accounted for relatively little of the variance in physical activity. The role of perceived sport/activity of the parents, especially among younger boys and girls, is particularly of interest and merits more detailed study. Nevertheless, many other variables also need to be considered.

Can we modulate physical activity in children?

There is concern that interventions that use physical activity to prevent obesity in children might be undermined by an 'Activitystat', which exerts an effect to maintain a low set point for physical activity. The present critique summarises evidence from systematic reviews of interventions, from empirical tests of the Activitystat hypothesis, from studies on the heritability of physical activity in childhood and the physical activity of children of and adolescents across a wide range of physical and cultural environments. This body of evidence is inconsistent with the Activitystat hypothesis in its current form, and suggests that the emphasis on physical activity in obesity prevention interventions in children should be increased, not reduced.

Child obesity and fitness levels among Kenyan and Canadian children from urban and rural environments: a KIDS-CAN Research Alliance Study

OBJECTIVE

This study was designed to gather anthropometric and fitness-related data on Kenyan children living in urban (UKEN) and rural (RKEN) environments and to compare them with previous data collected on Canadian children in order to examine the potential nutrition-physical activity transition.

METHODS

Height, weight, waist circumference, triceps skinfolds were directly measured on rural (RKEN) and urban Kenyan (UKEN) children (n = 179, 9-13 years) and compared with existing data from Canadian children living in urban and rural environments (n = 274, 9-13 years). Aerobic fitness was measured using the 20 m shuttle run, flexibility using the sit-and-reach test and isometric handgrip strength was assessed.

RESULTS

None of the RKEN children were overweight or obese (OWO). However, 6.8% of UKEN boys and 16.7% of girls were OWO. The RKEN children had lower BMI, waist circumference, and triceps skinfolds than all other groups (UKEN, and Canadian: p < 0.05). UKEN children were leaner than Canadian children (p < 0.05). Male and female RKEN children had higher running speeds, and aerobic fitness than UKEN children (p < 0.001). Isometric strength was not different between Kenyan groups and was not different from urban living Canadian children. UKEN children were the least flexible group, and girls were more flexible than boys in all groups.

CONCLUSIONS

Urban Kenyan children appear to be showing signs of the nutrition-physical activity transition, as judged by the anthropometric similarities to contemporary living Canadian children. Further support is provided by examining the difference in prevalence of overweight/obesity among UKEN compared with their RKEN counterparts and their lower aerobic fitness level.

A 10-month physical activity intervention improves body composition in young black boys

Objective. To determine if a 10-month after-school physical activity (PA) intervention could prevent deleterious changes in body composition and cardiovascular (CV) fitness in young black boys. Methods. Following baseline measures, 106 boys (8-12 yrs) were randomized to either a control group or an intervention group, further divided into attenders (ATT) and nonattenders (NATT), participating in ≥60% or <60% of the intervention, respectively. The daily intervention consisted of skills development (25 min), vigorous PA (VPA, 35 min), and strengthening/stretching (20 min) components. Body composition was measured by dual-energy X-ray absorptiometry. Results. Following the intervention, the ATT exhibited an increase in moderate-to-vigorous PA and a significant reduction in BMI, fat mass, and %BF compared to the control group. A significant association among the intervention energy expenditure and changes in body composition and CV fitness was observed only in the ATT group. Conclusion. An after-school PA program of sufficient length and intensity can promote healthy changes in body composition and fitness levels in black boys who attend at least 3 days/week.

Physical activity levels of children living in different built environments

OBJECTIVE

To review the available literature assessing differences in physical activity levels of children living in different built environments classified according to land use within developed countries.

METHODS

A systematic review of published literature up to March 2009. Online searches of five databases yielded 18 studies which met inclusion criteria. Studies provided data on n=129446, 5-18 years old (n=117544 from the United States).

RESULTS

From 13 assessments of differences in physical activity between rural and urban children one showed that rural children were significantly more active than urban children. In studies where the built environment was sub-divided further, suburban and small town children showed the highest levels of physical activity, followed by rural, then urban children. Differences in types of physical activity undertaken were evident, showing that rural children spent more time outdoors, involved in unstructured play compared with urban children. These findings were mainly restricted to children <13 years old.

CONCLUSIONS

The literature does not show major differences in the physical activity levels between children from rural or urban areas. Where studied, the suburban built environment appears most conducive to promoting physical activity. Further research should use at least a trilateral division of the built environment and should also account for socioeconomic status, racial factors and seasonal effects.

Accelerometer assessment of physical activity in active, healthy older adults

Despite widespread use of accelerometers to objectively monitor physical activity among adults and youth, little attention has been given to older populations. The purpose of this study was to define an accelerometer-count cut point for a group of older adults and to then assess the group's physical activity for 7 days. Participants (N = 38, age 69.7 +/- 3.5 yr) completed a laboratory-based calibration with an Actigraph 7164 accelerometer. The cut point defining moderate to vigorous physical activity (MVPA) was 1,041 counts/min. On average, participants obtained 68 min of MVPA per day, although more than 65% of this occurred as sporadic activity. Longer bouts of activity occurred in the morning (6 a.m. to 12 p.m.) more frequently than other times of the day. Almost 14 hr/day were spent in light-intensity activity. This study demonstrates the rich information that accelerometers provide about older adult activity patterns-information that might further our understanding of the relationship between physical activity and healthy aging.

Elevated blood pressure in relation to overweight and obesity among children in a rural Canadian community

OBJECTIVE

Childhood overweight and obesity may result in premature onset of cardiovascular risk factors such as hypertension. Rural populations in North America may be at increased risk for overweight. We evaluated whether overweight and obesity were associated with prehypertension and hypertension in a well-characterized population of children in rural Canada.

METHODS

The study population for this cross-sectional study was composed of children (aged 4-17 years) who were participants of the Walkerton Health Study (Canada) in 2004. Prehypertension and hypertension were defined on the basis of percentiles from the average of 3 blood pressure measures taken on a single occasion. Percentiles for BMI and blood pressure were calculated by using the 2000 Centers for Disease Control and Prevention growth charts. Multinomial logistic regression was used to evaluate the odds for prehypertension and hypertension resulting from overweight and obesity.

RESULTS

Of 675 children (98.7% white), 122 (18.1%) were overweight and 77 (11.4%) were obese. Prehypertension and hypertension were detected in 51 (7.6%) and 50 (7.4%), respectively. After adjustment for family history of hypertension and kidney disease, obesity was associated with both prehypertension and hypertension. Overweight was associated with hypertension but not prehypertension. These associations were observed across the genders and children aged <13 and >or=13 years, except that overweight was not associated with hypertension among girls.

CONCLUSIONS

In this population of children who lived in a rural community in Canada, overweight and obesity were strongly associated with elevated blood pressure. Whether blood pressure normalizes with improvements in diet, physical activity, and environment is an area for additional study.

Moving forward by looking back: lessons learned from long-lost lifestyles

The paper briefly reviews the status and trends in physical activity, physical inactivity, and overweight/obesity in Canada; discusses the consequences of these trends; examines evidence that our frame of reference with respect to physical activity and obesity is changing; promotes the importance of getting “back to the basics” as a strategy for enhancing childhood physical activity; and provides suggestions for future research in this area. In addressing these topics, the paper explores and contrasts the lifestyles and characteristics of Old Order Amish and Old Order Mennonite children with children exposed to contemporary modern living. This exploration is used as a model to learn from traditional lifestyles, which were comparatively active and resistant to obesity. The fitness characteristics and physical activity levels of traditional and contemporary groups are compared and demonstrate significant differences among groups. This evidence may provide important insight for informing future physical activity recommendations. Idiosyncrasies of performing research on these traditional-living groups are also provided.

Physical activity of Canadian and American children: a focus on youth in Amish, Mennonite, and modern cultures

Childhood obesity is an urgent public health problem in North America and throughout most of the industrialized world. Diminishing levels of physical activity and the growth of sedentary pursuits may be contributing to the obesity epidemic. The advent of modern technological societies has brought about dramatic changes in lifestyle over the past century. To gain insights into physical activity levels in pre-industrial era societies, researchers have turned to studying religious groups that have resisted the lure of technological change. Children in Old Order Amish and Old Order Mennonite communities of North America have a lifestyle that still involves walking to school and friends' homes, performing chores, caring for farm animals, and active play. Research has shown that Amish and Mennonite children have higher levels of physical activity than modern-living children, despite less participation in organized competitive sports. As a result, Amish and Mennonite children tend to be leaner than their counterparts in contemporary society. Studying non-mainstream cultures can provide a valuable perspective on human behaviors.

Early life determinants of physical activity in 11 to 12 year olds: cohort study

OBJECTIVE

To examine factors in early life (up to age 5 years) that are associated with objectively measured physical activity in 11-12 year olds.

DESIGN

Prospective cohort study.

SETTING

Avon longitudinal study of parents and children, United Kingdom.

PARTICIPANTS

Children aged 11-12 years from the Avon longitudinal study of parents and children.

MAIN OUTCOME MEASURE

Physical activity levels in counts per minute (cpm) and minutes of moderate to vigorous physical activity for seven days measured with a uniaxial actigraph accelerometer.

RESULTS

Valid actigraph data, defined as at least three days of physical activity for at least 10 hours a day, were collected from 5451 children. Several factors were associated with physical activity at ages 11-12 years. Regression coefficients are compared with the baseline of "none" for categorical variables: maternal brisk walking during pregnancy (regression coefficient 5.0, 95% confidence interval -8.5 to 18.5; cpm for <1 h/wk and > or =2 h/wk of physical activity 17.7, 5.3 to 30.1), maternal swimming during pregnancy (21.5, 10.9 to 32.1 and cpm for <1 h/wk and > or =2 h/wk of physical activity 24.2, 7.8 to 40.7), parents' physical activity when the child was aged 21 months (28.5, 15.2 to 41.8 and cpm of physical activity for either parent active and both parents active 33.5, 17.8 to 49.3), and parity assessed during pregnancy (2.9, -7.6 to 13.4 and cpm of physical activity for 1 and > or =2 parity 21.2, 7.1 to 35.3).

CONCLUSIONS

Few factors in early life predicted later physical activity in 11-12 year olds. Parents' physical activity during pregnancy and early in the child's life showed a modest association with physical activity of the child at age 11-12 years, suggesting that active parents tend to raise active children. Helping parents to increase their physical activity therefore may promote children's activity.

Établissement du profil de l’activité physique et de l’inactivité : la prochaine générationCet article est tiré d’un supplément intitulé Advancing physical activity measurement and guidelines in Canada: a scientific review and evidence-based foundation for the future of Canadian physical activity guidelines (Favoriser les lignes directrices et la mesure de l’activité physique au Canada: examen scientifique et justification selon les données probantes pour l’avenir des lignes directrices de l’activité physique canadienne) publié par Physiologie appliquée, nutrition et métabolisme et la Revue canadienne de santé publique. On peut aussi mentionner Appl. Physiol. Nutr. Metab. 32 (Suppl. 2F) ou Can. J. Public Health 98 (Suppl. 2)

L’évaluation précise de la quantité d’activité physique pratiquée de façon régulière constitue une donnée fondamentale dans l’étude de la relation entre l’activité physique et la santé. Cependant, plusieurs techniques de mesure de l’activité physique ne donnent que des résultats valables pour une seule journée comme, par exemple, la dépense d’énergie réalisée d’après une auto-évaluation par questionnaire, le nombre de pas fait d’après un podomètre, l’intensité d’activité physique mesurée au moyen d’un accéléromètre comptant le temps à faire des exercices d’intensité modérée à vigoureuse. On peut maintenant utiliser les techniques de monitorage qui informent davantage sur les comportements actifs et sédentaires pour approfondir l’étude de la relation entre la santé et la fréquence, l’intensité et la durée des mouvements accomplis. Cet article présente comment un monitorage objectif, avec une attention particulière portée à l’accélérométrie, peut dresser un bilan d’activité / d’inactivité. Au moyen de données objectives prélevées dans la littérature, on présente un bilan kinésique détaillé et des exemples d’étude de cas incorporant des données et leur interprétation. La quantité d’informations recueillies dans ce profil complet offre de nouvelles avenues de surveillance et d’études scientifiques pouvant déboucher sur de nouvelles directives en matière de pratique de l’activité physique. Nous présentons les résultats de diverses façons pour démontrer les dangers d’une mauvaise interprétation des données quand on évalue une population d’après son taux de conformité aux directives contenues dans le Guide d’activité physique canadien. Nous énonçons des recommandations en matière de profil kinésique / akinésique et nous proposons quelques pistes de recherche.

Physical activity and inactivity profiling: the next generationThis article is part of a supplement entitled Advancing physical activity measurement and guidelines in Canada: a scientific review and evidence-based foundation for the future of Canadian physical activity guidelines co-published by Applied Physiology, Nutrition, and Metabolism and the Canadian Journal of Public Health. It may be cited as Appl. Physiol. Nutr. Metab. 32(Suppl. 2E) or as Can. J. Public Health 98(Suppl. 2)

The accurate measurement of habitual physical activity is fundamental to the study of the relationship between physical activity and health. However, many physical activity measurement techniques produce variables accurate to only the day level, such as total energy expenditure via self-report questionnaire, pedometer step counts, or accelerometer measurements of minutes of moderate to vigorous physical activity. Monitoring technologies providing more detailed information on physical activity and inactivity behaviour can now be used to explore the relationships between health and movement frequency, intensity, and duration more comprehensively. This paper explores the activity–inactivity profile that can be acquired through objective monitoring, with a focus on accelerometry. Using previously collected objective data, a detailed physical activity profile is presented and case study examples of data utilization and interpretation are provided. The rich detail captured through comprehensive profiling creates new surveillance and study possibilities and could possibly inform new physical activity guidelines. Data are presented in various formats to demonstrate the dangers of misinterpretation when monitoring population adherence to Canada’s physical activity guidelines. Recommendations for physical activity–inactivity profiling are provided and future research needs identified.

Physical activity patterns and sedentary behaviors of children from urban and rural areas of Cyprus

BACKGROUND

A sedentary lifestyle among children is becoming increasingly common and has been linked to future risk of degenerative diseases. Urban residence has been suggested to be a contributing factor to a less active lifestyle; however, not all available studies support this link. In the present study we examined the physical activity patterns and sedentary behaviours of children living in urban and rural areas of Cyprus, where major demographic shifts have occurred the last decades.

METHODS

We studied 1140 children (531 boys; 609 girls), aged 10-12 years, registered in 24 selected elementary public schools from five urban and rural districts of Cyprus. Children completed a semi-quantitative physical activity questionnaire regarding frequency and duration of everyday physical and sedentary activities. Weight and height of the children, as well as demographic and socioeconomic information was collected from children and their guardians.

RESULTS

Rural children reported being slightly more active after school and occupied weekly with outdoors chores compared to urban children, who on the other hand reported engaging in sports on a weekly basis more than their rural peers (all p < 0.10). However, the average weekly time spent by urban and rural children on vigorous (8.6 +/- 4.7 and 9.1 +/- 4.8 h/w, respectively; p = 0.193) or moderate-to-vigorous (14.9 +/- 7.6 and 15.2 +/- 7.6 h/w, respectively; p = 0.612) activities, as well as total screen time, were not different. The distribution of children with regards to most other physical activity and inactivity pursuits was similar between urban and rural areas.

CONCLUSION

We found no substantial differences in the physical activity habits and sedentary behaviours among children living in urban and rural areas of Cyprus. Hence public health awareness directed to enhance physical activity and decrease sedentary lifestyle among youngsters should focus equally to urban and rural children.

Age and Gender Differences in Youth Physical Activity

PURPOSE

To investigate whether observed gender differences in objectively measured physical activity (PA) in children (8-13 yr) are confounded by physical maturity differences.

METHODS

Four hundred and one children (194 boys and 207 girls) volunteered for this study. An Actigraph accelerometer was used to obtain seven consecutive days of minute-by-minute PA data for each participant. Minutes of moderate to vigorous PA per day (MVPA), continuous minutes of MVPA per day (CMVPA), and minutes of vigorous PA per day (VPA) were derived from the accelerometer data. Age at peak height velocity (APHV), an indicator of somatic maturity, was predicted in all individuals. Gender differences in the PA variables were analyzed using a two-way (gender x age) ANOVA.

RESULTS

Levels of PA decreased with increasing chronological age in both genders (P < 0.05). When aligned on chronological age, boys had a higher MVPA at 10-13 yr, a higher CMVPA at 9-12 yr, and a higher VPA at 9-13 yr (P < 0.05). When aligned on biological age, PA declined with increasing maturity (P < 0.05); however, gender differences between biological age groups disappeared.

CONCLUSION

The observed age-related decline in adolescent boys and girls PA is antithetical to public health goals; as such, it is an important area of research. To fully understand gender disparities in PA, consideration must be given to the confounding effects of physical maturity.

Physical Activity and Body Mass Index of Children in an Old Order Amish Community

The prevalence of childhood obesity is rapidly increasing in many countries throughout the world. Advances in modern technology may have contributed to this problem by reducing children's physical activity levels. Thus, it is interesting to study children belonging to groups that have refrained from adopting modern technology.

PURPOSE

This study examined the physical activity levels and body mass index (BMI) of Old Order Amish children and adolescents living in a nontechnological farming community.

METHODS

One hundred thirty-nine Amish youth (6-18 yr of age) were recruited for the study. BMI was computed from measured height and weight. The schoolchildren were instructed to wear sealed step counters for 7 d. Each school day, research assistants opened the step counters, recorded their steps, reset and resealed them, and placed them back on the children. Older children recorded their steps on a step-counter log sheet.

RESULTS

The number of steps per day (mean +/- SD) was 17,525 +/- 4443 (measured for four weekdays), 10,661 +/- 4208 (measured over Friday, Saturday, and Sunday), and 15,563 +/- 3702 (measured for 7 d). All of the step variables (P < 0.001) showed gender effects, but there were no significant age effects. Only 7.2% of the youth were overweight, and only 1.4% were obese.

CONCLUSION

These Amish youth have high levels of physical activity, and obesity is rare. Comparing our results with those of other studies, it is evident that these Amish youth are more physically active and have a lower rate of obesity than children living in modern, industrialized societies.

Think tank on school-aged children: nutrition and physical activity to prevent the rise in obesity

The rise in childhood obesity has generated concern across a range of sectors. Stakeholders and experts in the area of children’s health met at a Think Tank in Toronto organized by the Canadian Council for Food and Nutrition and the Program in Food Safety, Nutrition, and Regulatory Affairs at the University of Toronto to discuss the current evidence in place to inform the development of school policies to reduce childhood obesity. Although there is some evidence to suggest that school interventions may reduce obesity in children, there are other examples of programs that have had very little impact. The role of parents in the development of healthy eating and physical activity patterns is critical from the earliest stages of life and warrants further attention. Delegates agreed that we need ongoing input of experts and leaders from all sectors and fields to help us to effectively promote healthy lifestyles at schools and within the home, while respecting each child's need for safety, security, and respect.