Flo Harrison

Physical activity and dietary behaviour in a population-based sample of British 10-year old children: the SPEEDY study (Sport, Physical activity and Eating behaviour: environmental Determinants in Young people).

BackgroundThe SPEEDY study was set up to quantify levels of physical activity (PA) and dietary habits and the association with potential correlates in 9–10 year old British school children. We present here the analyses of the PA, dietary and anthropometry data.MethodsIn a cross-sectional study of 2064 children (926 boys, 1138 girls) in Norfolk, England, we collected anthropometry data at school using standardised procedures. Body mass index (BMI) was used to define obesity status. PA was assessed with the Actigraph accelerometer over 7 days. A cut-off of ≥ 2000 activity counts was used to define minutes of moderate-to-vigorous PA (MVPA). Dietary habits were assessed using the Health Behaviour in School Children food questionnaire. Weight status was defined using published international cut-offs (Cole, 2000). Differences between groups were assessed using independent t-tests for continuous data and chi-squared tests for categorical data.ResultsValid PA data (>500 minutes per day on ≥ 3 days) was available for 1888 children. Mean (± SD) activity counts per minute among boys and girls were 716.5 ± 220.2 and 635.6 ± 210.6, respectively (p < 0.001). Boys spent an average of 84.1 ± 25.9 minutes in MVPA per day compared to 66.1 ± 20.8 among girls (p < 0.001), with an average of 69.1% of children accumulating 60 minutes each day. The proportion of children classified as overweight and obese was 15.0% and 4.1% for boys and 19.3% and 6.6% for girls, respectively (p = 0.001). Daily consumption of at least one portion of fruit and of vegetables was 56.8% and 49.9% respectively, with higher daily consumption in girls than boys and in children from higher socioeconomic backgrounds.ConclusionResults indicate that almost 70% of children meet national PA guidelines, indicating that a prevention of decline, rather than increasing physical activity levels, might be an appropriate intervention target. Promotion of daily fruit and vegetable intake in this age group is also warranted, possibly focussing on children from lower socioeconomic backgrounds.

Seasonal variation in children’s physical activity and sedentary time

ABSTRACT Purpose Understanding seasonal variation in physical activity is important for informing public health surveillance and intervention design. The aim of the current study was to describe seasonal variation in children’s objectively measured physical activity and sedentary time. Methods Data are from the UK Millennium Cohort Study. Participants were invited to wear an accelerometer for 7 d on five occasions between November 2008 and January 2010. Outcome variables were sedentary time (<100 counts per minute, min·d−1) and moderate to vigorous physical activity (MVPA) (>2241 counts per minute, min·d−1). The season was characterized using a categorical variable (spring, summer, autumn, or winter) and a continuous function of day of the year. Cross-classified linear regression models were used to estimate the association of each of these constructs with the outcome variables. Modification of the seasonal variation by sex, weight status, urban/rural location, parental income, and day of the week (weekday/weekend) was examined using interaction terms in regression models. Results At least one wave of valid accelerometer data was obtained from 704 participants (47% male; baseline age, 7.6 (0.3) yr). MVPA was lower in autumn and winter relative to spring, with the magnitude of this difference varying by weekday/weekend, sex, weight status, urban/rural location, and family income (P for interaction <0.05 in all cases). Total sedentary time was greater in autumn and winter compared with spring; the seasonal effect was stronger during the weekend than during the weekday (P for interaction <0.01). Conclusions Lower levels of MVPA and elevated sedentary time support the implementation of intervention programs during autumn and winter. Evidence of greater seasonal variation in weekend behavior and among certain sociodemographic subgroups highlights targets for tailored intervention programs.

Impact of neighbourhood food environment on food consumption in children aged 9–10 years in the UK SPEEDY (Sport, Physical Activity and Eating behaviour: Environmental Determinants in Young people) study

OBJECTIVE Poor diet in childhood increases risk of obesity but the relationship between access to food and childrens food choice is underexplored. We determined relationships between distance to and density of food outlets on childrens food choice. DESIGN Children (n 1721) aged 9-10 years who participated in a cross-sectional study from a sample of state and private schools across urban and rural areas. Food consumption was reported using a short validated FFQ. A Geographic Information System was used to determine proximity to local food outlets. Multivariable regression analyses were performed to determine associations between food consumption and distance to and density of local food outlets. SETTING Norfolk, England. SUBJECTS Boys (n 754) and girls (n 967) aged 9-10 years. RESULTS The impact of distance to or density of food outlets on food choice was small after adjustment. Living further away from a supermarket increased portions of fruit (0.11 portions/week per 1 km increase in distance to nearest supermarket, P < 0.05) and vegetables (0.11 portions/week, P < 0.05) consumed. Living closer to convenience stores was also associated with an increased consumption of crisps, chocolate and white bread. Density of supermarkets was associated with both an increase in vegetable intake (0.31 portions/week, P < 0.05) and unhealthy foods. CONCLUSIONS Distance to and density of food outlets are both associated with childrens food choice, although the impact appears to be small and the relationship is complex. However, the effects of individual foods combined could be important, particularly as even small differences in intake can impact on body weight over time.

School environments and physical activity: The development and testing of an audit tool.

The aim of this study was to develop, test, and employ an audit tool to objectively assess the opportunities for physical activity within school environments. A 44 item tool was developed and tested at 92 primary schools in the county of Norfolk, England, during summer term of 2007. Scores from the tool covering 6 domains of facility provision were examined against objectively measured hourly moderate to vigorous physical activity levels in 1868 9-10 year old pupils attending the schools. The tool was found to have acceptable reliability and good construct validity, differentiating the physical activity levels of children attending the highest and lowest scoring schools. The characteristics of school grounds may influence pupils physical activity levels.

Cryptosporidiosis Decline after Regulation, England and Wales, 1989-2005

Since new drinking water regulations were implemented in England and Wales in 2000, cryptosporidiosis has been significantly reduced in the first half of the year but not in the second. We estimate an annual reduction in disease of 905 reported cases and ≈6,700 total cases.

Environmental correlates of adiposity in 9-10 year old children: Considering home and school neighbourhoods and routes to school

The rapid speed of the recent rise in obesity rates suggest environmental causes. There is therefore a need to determine which components of the environment may be contributing to this increase. In this cross-sectional study, we examined the associations between adiposity and the characteristics of areas around homes, schools and routes to school among 1995 9-10 year old boys and girls in Norfolk, UK. The relationships between Fat Mass Index (FMI, calculated as fat mass (kg)/height (m)(2)) and objectively computed environmental indicators describing access to food outlets and physical activity facilities, the safety and connectivity of the road network, and the mix of land uses present were investigated. Multivariable hierarchical regression models were fitted with log-transformed FMI as the outcome, and stratification by gender and mode of travel to school. Among girls, better access to healthy food outlets (supermarkets and greengrocers) in the home environment was associated with lower FMI while better access to unhealthy outlets (takeaways and convenience stores) around homes and schools was associated with higher FMI. Also in girls, a higher proportion of accessible open land and a lower mix of land uses around the school were associated with higher FMI. Among boys the presence of major roads in the home neighbourhood was associated with higher FMI among non-active travellers, while major roads in the school neighbourhood were associated with lower FMI among active travellers. No significant associations were seen between FMI and any of the route characteristics. While the relative paucity of associations provides few indicators for the design of effective interventions, there was some evidence that environmental characteristics may be more important among active travellers than non-active travellers, and among girls than boys, suggesting that future interventions should be sensitive to such differences.

A framework for understanding school based physical environmental influences on childhood obesity

Schools are inviting settings for the promotion of healthy behaviours in children, and a number of interventions have been trialled to improve diet or increase physical activity levels with the ultimate aim of reducing the prevalence of obesity. However, these have seen mixed results and there is suggestion that consideration needs to be given to a broader definition of the school environment in order to encourage sustainable behaviour changes. This review considers evidence for associations between the physical school environment and diet, physical activity and adiposity. School environment covers the neighbourhood around the school as well as the school grounds, buildings and facilities. Reviewed evidence is used to construct a conceptual framework for understanding associations between the physical school environment and adiposity and related behaviours. The framework highlights how school environments may be modified to promote behaviour changes, and how they may limit or enhance the success of other school-based interventions. Consideration is also given to where future work may best be directed.

The impact of rainfall and school break time policies on physical activity in 9-10 year old British children: a repeated measures study

BackgroundThe weather may be a driver of seasonal patterns in childrens physical activity (PA). A better understanding of the relationships between weather and PA may help increase childrens PA. This study aims to examine the association between PA and rainfall in 9-10 year old children, and how it may be modified by school policies.Methods1794 participants in the SPEEDY study in Norfolk, UK recorded PA using ActiGraph accelerometers over up to six days in the summer term of 2007. Multilevel regression models were used to determine the day-by-day association between rainfall and minutes spent sedentary, in moderate-to-vigorous PA (MVPA), and average counts per minute (cpm) over the whole day (07:00-21:00) and the lunchtime period (12:00-14:00). School policies for break times in bad weather were fitted as interaction terms with rainfall.ResultsRelative to days with no rain, children spent 9.4 minutes (95%CI 7.0 to 11.9) fewer in MVPA, were sedentary for 13.6 minutes (8.8 to 18.4) more, and accumulated 85.9 cpm (66.2 to 105.5) fewer over the whole day on the wettest days. Children allowed to play outside in wet weather showed the lowest lunchtime PA levels on the wettest days, undertaking 9.8 minutes (6.2 to 13.5) fewer MVPA, 16.1 minutes (10.3 to 21.9) more sedentary, and accumulating 408.0 cpm (250.9 to 565.1) fewer than those allowed to be active indoors.ConclusionsRainfall is negatively associated with PA in primary school children, but providing indoor physical activities in wet weather may help children maintain physical activity levels irrespective of rainfall.

Comparing the accuracy of two secondary food environment data sources in the UK across socio-economic and urban/rural divides

BackgroundInterest in the role of food environments in shaping food consumption behaviours has grown in recent years. However, commonly used secondary food environment data sources have not yet been fully evaluated for completeness and systematic biases. This paper assessed the accuracy of UK Points of Interest (POI) data, compared to local council food outlet data for the county of Cambridgeshire.MethodsPercentage agreement, positive predictive values (PPVs) and sensitivities were calculated for all food outlets across the study area, by outlet type, and across urban/rural/SES divisions.ResultsPercentage agreement by outlet type (29.7-63.5%) differed significantly to overall percentage agreement (49%), differed significantly in rural areas (43%) compared to urban (52.8%), and by SES quintiles. POI data had an overall PPV of 74.9%, differing significantly for Convenience Stores (57.9%), Specialist Stores (68.3%), and Restaurants (82.6%). POI showed an overall ‘moderate’ sensitivity, although this varied significantly by outlet type. Whilst sensitivies by urban/rural/SES divides varied significantly from urban and least deprived reference categories, values remained ‘moderate’.ConclusionsResults suggest POI is a viable alternative to council data, particularly in terms of PPVs, which remain robust across urban/rural and SES divides. Most variation in completeness was by outlet type; lowest levels were for Convenience Stores, which are commonly cited as ‘obesogenic’.

Food and drink consumption at school lunchtime: the impact of lunch type and contribution to overall intake in British 9–10-year-old children

OBJECTIVE To examine the differences in dietary intakes of children consuming school meals and packed lunches, the contribution of lunchtime intake to overall dietary intake, and how lunchtime intake relates to current food-based recommendations for school meals. DESIGN Cross-sectional analysis of overall intake of macronutrients and food choice from 4 d food diaries and school lunchtime intake from the two diary days completed while at school. SETTING Norfolk, UK. SUBJECTS One thousand six hundred and twenty-six children (aged 9-10 years) attending ninety Norfolk primary schools. RESULTS At school, lunchtime school meal eaters consumed more vegetables, sweet snacks, chips, starchy foods and milk, and less squash/cordial, fruit, bread, confectionery and savoury snacks than packed lunch eaters. These differences were also reflected in the overall diet. On average school meal eaters met the School Food Trust (SFT) food-based standards, while food choices among packed lunch eaters were less healthy. The contribution of food consumed at school lunchtime to overall diet varied by food and lunch type, ranging from 0.8 % (milk intake in packed lunches) to 74.4 % (savoury snack intake in packed lunches). CONCLUSIONS There were significant differences in the foods consumed by school meal and packed lunch eaters, with food choices among school meal eaters generally in line with SFT standards. The food choices made at school lunchtime make a significant contribution to overall diet.