Association between community characteristics and implementation of community programmes and policies addressing childhood obesity: the Healthy Communities Study.

BACKGROUND: Little is known about whether characteristics of communities are associated with differential implementation of community programmes and policies to promote physical activity and healthy eating. This study examines associations between community characteristics (e.g. region and race/ethnicity) and the intensity of community programmes and policies implemented to prevent childhood obesity. It explores whether community characteristics moderate the intensity of community efforts to prevent childhood obesity. OBJECTIVE: The objective of this study is to investigate associations between community characteristics and the intensity of community policies and programmes to prevent childhood obesity documented in the Healthy Communities Study that engaged a diverse sample of US communities. METHOD: Programmes and policies were documented in 130 communities across the USA, reporting over 9000 different community programmes and policies to prevent obesity among children ages 4-15. We examined associations between community characteristics and the intensity of community programmes and policies implemented (i.e. their amount and reach, duration and strength of change strategy). CONCLUSION: Community characteristics explain 25% of the variability in the intensity of community programmes and policies implemented in communities. Particular characteristics - urbanicity, region, being a large county and the per cent of African-Americans in a community - contributed to more (over 18% of the 25%) of the observed variability.

Relationship of objective street quality attributes with youth physical activity: findings from the Healthy Communities Study.

BACKGROUND: Residential environments may significantly influence youth physical activity (PA). However, few studies have examined detailed street quality attributes via observational audits in relation to context-specific PA among youth. OBJECTIVES: The objective of this study was to explore whether the overall quality of street environments, as well as specific attributes, was associated with neighbourhood-based and street-based PA within a national sample of youth in the Healthy Communities Study. METHODS: Data were collected from 4616 youth from 130 communities across the USA. Youth PA in the neighbourhood and on the participant's street was captured using 7-d recall interviews. Windshield survey observational audits documented five street quality variables: burned, boarded up or abandoned residential units, litter, overall condition of residences, street type and presence of sidewalks in good condition. RESULTS: Youth with no litter on their street reported significantly lower neighbourhood-based PA and youth living on a side street, cul-de-sac, dead-end or one-way street reported greater neighbourhood-based PA. No significant associations were detected for the overall street quality index or with street-based PA. CONCLUSIONS: Specific street quality attributes may be associated with youth PA. Further research and collaboration between diverse disciplines and agencies should focus on understanding and improving street quality to promote youth PA and health.

Associations between community programmes and policies and children's physical activity: the Healthy Communities Study.

BACKGROUND: Community initiatives to promote physical activity in children are common, but evidence supporting their effectiveness is limited. OBJECTIVES: The objective of this study is to examine the relationships between community programmes and policies and children's physical activity in a large and diverse sample of US communities. METHODS: Programmes and policies to promote children's physical activity were assessed in 130 communities by key informant interviews, and physical activity behaviours were measured by self-report and parental report in samples of children in each community (total n = 5138). Associations between composite indices of community programmes and policies and indicators of total and moderate-to-vigorous physical activity were examined without and with adjustment for demographic factors. RESULTS: An index reflecting the 6-year history of the number of behaviour change strategies used in community programmes and policies was positively associated with children's moderate-to-vigorous physical activity. This association was attenuated with adjustment for demographic factors. Effect modification analyses found that the association was positive among non-Hispanic children but was negative for Hispanic children. CONCLUSIONS: Community initiatives to promote physical activity in children were positively associated with children's physical activity in non-Hispanic children. Such initiatives were negatively associated with physical activity in Hispanic children, suggesting that future research should consider unique cultural factors when designing community initiatives to promote activity in this population sub-group.

The longitudinal relationship between community programmes and policies to prevent childhood obesity and BMI in children: the Healthy Communities Study.

BACKGROUND: Although a national epidemic of childhood obesity is apparent, how community-based programmes and policies (CPPs) affect this outcome is not well understood. OBJECTIVES: This study examined the longitudinal relationship between the intensity of CPPs in 130 communities over 10 years and body mass index (BMI) of resident children. We also examined whether these relationships differ by key family or community characteristics. METHODS: Five thousand one hundred thirty-eight children in grades K-8 were recruited through 436 schools located within 130 diverse US communities. Measures of height, weight, nutrition, physical activity and behavioural and demographic family characteristics were obtained during in-home visits. A subsample of families consented to medical record review; these weight and height measures were used to calculate BMI over time for 3227 children. A total of 9681 CPPs were reported during structured interviews of 1421 community key informants, and used to calculate a time series of CPP intensity scores within each community over the previous decade. Linear mixed effect models were used to assess longitudinal relationships between childhood BMI and CPP intensity. RESULTS: An average BMI difference of 1.4 kg/m2 (p-value < 0.01) was observed between communities with the highest and lowest observed CPP intensity scores, after adjusting for community and child level covariates. BMI/CPP relationships differed significantly by child grade, race/ethnicity, family income and parental education; as well as community-level race/ethnicity. CONCLUSIONS: These results indicate that, over time, more intense CPP interventions are related to lower childhood BMI, and that there are disparities in this association by sociodemographic characteristics of families and communities.

Physical activity behaviours of highly active preschoolers.

BACKGROUND: Understanding the physical activity behaviour of young children who are highly active may provide important guidance for promoting physical activity in preschools. OBJECTIVES: The objective of this study was to describe the movement characteristics of high-active (HA) children during attendance at preschools. METHODS: Children in 20 preschools (n = 231) wore accelerometers and were classified into tertiles of moderate-to-vigorous physical activity. Children's movement characteristics were observed using the Observational System for Recording Physical Activity in Children-Preschool Version. Mixed-model analyses compared movement types between HA children and lower-active (LA) children during the total school day. RESULTS: HA (n = 77) children were observed to be more active than LA children (n = 154) indoors (P < 0.001), but no differences were observed outdoors. HA children were more frequently observed running, crawling, climbing, jumping, skipping, swinging and throwing across the total school day than LA children. Outdoors, HA children participated in more swinging and throwing and less jumping or skipping than LA children. Indoors, HA children spent more time pulling, pushing and running, and less time walking than LA children. CONCLUSIONS: HA children have unique activity patterns. Further interventions to increase physical activity of all preschoolers should increase the time spent outside and include varied activity types throughout the entire school day.

NO-mediated alterations in skeletal muscle nutritive blood flow and lactate metabolism in fibromyalgia.

UNLABELLED: The purpose of these investigations was to determine if differences exist in skeletal muscle nutritive blood flow and lactate metabolism in women with fibromyalgia (FM) compared to healthy women (HC); furthermore, to determine if differences in nitric oxide-mediated systems account for any detected alterations in blood flow and lactate metabolism and contribute to exertional fatigue in FM. FM (n = 8) and HC (n = 8) underwent a cycle ergometry test of aerobic capacity, a muscle biopsy for determination of nitric oxide synthase (eNOS, nNOS, iNOS) content, and microdialysis for investigation of muscle nutritive blood flow and lactate metabolism. During prolonged (3h) resting conditions, the ethanol outflow/inflow ratio (inversely related to blood flow) increased in FM over time compared to HC (P < 0.05). FM also exhibited a reduced nutritive blood flow response to aerobic exercise (P < 0.05). There was an increase in dialysate lactate in response to acetylcholine in FM, and to sodium nitroprusside in both groups, with a greater rise in dialysate lactate in FM (P < 0.05). The iNOS protein content was higher in FM and was negatively correlated with total exercise time (r(2) = 0.462, P < 0.05). IN CONCLUSION: (1) There is reduced nutritive flow response to aerobic exercise and reduced maximal exercise time in FM that might relate to higher iNOS protein content and contribute to exertional fatigue in FM; (2) The increased dialysate lactate in FM in response to stimulation of NOS or a nitric oxide donor suggest that FM may be more sensitive than HC to the suppressive effect of nitric oxide on oxidative phosphorylation.

Relationship between body composition and skeletal muscle eNOS.

OBJECTIVE: Owing to the relationship between nitric oxide related endothelial dysfunction, insulin resistance and cardiovascular disease in overweight individuals, we investigated if skeletal muscle endothelial nitric oxide synthase (eNOS) protein content and activity are lower in overweight than lean women. DESIGN: A total of 19 women (age 26.0+/-1.7 years) underwent a resting muscle biopsy, body composition analysis by hydrostatic weighing and peak aerobic capacity determination using indirect calorimetry (Study 1). An additional separate set of six lean (< or = 25% fat) and six overweight (>25% fat) women were subsequently studied for the determination of eNOS activity, and to better control for absolute peak aerobic capacity between lean and overweight women (Study 2). RESULTS: Skeletal muscle eNOS content was inversely related to percent body fat (r2 = 0.58, P < 0.01), and body mass index (r2 = 0.35, P < 0.05). Total eNOS activity was lower in overweight than lean women (2.09 +/- 0.22 vs 1.44 +/- 0.17 U, P < 0.05; n = 12), and was inversely related to percent body fat (r2 = 0.32, P = 0.05), and BMI (r 2 = 0.41, P < 0.05). Absolute and relative aerobic capacity were not independent predictors of skeletal muscle eNOS content (r2 = 0.11 and 0.26, respectively). CONCLUSION: There is an inverse relationship between eNOS and percent body fat that may have implications for the previously reported reduced endothelial function and insulin sensitivity in overweight women.