Street connectivity, physical activity, and childhood obesity: A systematic review and meta-analysis

Relationships Between Measures of the Physical Activity-Related Built Environment and Excess Weight in Preschoolers: A Retrospective, Population-Level Cohort Study

Background: The built environment can impact health outcomes. Our purpose was to examine relationships between built environment variables related to physical activity and excess weight in preschoolers. Methods: In this retrospective, population-level study of 4- to 6-year-olds, anthropometric measurements were taken between 2009 and 2017 in Calgary and Edmonton, Alberta, Canada. Based on BMI z-scores (BMIz), children were classified as normal weight (-2 ≤ BMIz <1) or excess weight (BMIz ≥1; overweight and obesity). Physical activity-related built environment variables were calculated (distances to nearest playground, major park, school; street intersection density; number of playgrounds and major parks within an 800 m buffer zone). Binomial logistic regression models estimated associations between physical activity-related built environment variables and excess weight. Results: Our analysis included 140,368 participants (females: n = 69,454; Calgary: n = 84,101). For Calgary, adjusted odds ratios (aORs) showed the odds of excess weight increased 1% for every 100-intersection increase [1.010 (1.006-1.015); p < 0.0001] and 13.6% when there were ≥4 playgrounds (vs. 0 or 1) within an 800 m buffer zone [1.136 (1.037-1.243); p = 0.0059]. For Edmonton, aORs revealed lower odds of excess weight for every 100 m increase in distances between residences to nearest major park [0.991 (0.986-0.996); p = 0.0005] and school [0.992 (0.990-0.995); p < 0.0001]. The odds of excess weight decreased as the number of major parks within the 800 m buffer zone increased from 0 to 1 [0.943 (0.896-0.992); p = 0.023] and from 0 to ≥3 [0.879 (0.773-0.999); p = 0.048]. Conclusion: The physical activity-related built environment was associated with excess weight in preschoolers, although relationships varied between cities that differed demographically and geographically.

The built environment and child obesity: A review of Australian policies

Child obesity is a serious public health challenge affected by both individual choice and societal and environmental factors. The main modifiable risk factors for child obesity are unhealthy eating and low levels of physical activity, both influenced by aspects of the built environment. Coordinated government policy across jurisdictions, developed using strong research evidence, can enable built environments that better support healthy lifestyles. This study reviewed current Australian and Western Australian government policies to understand if and how they address the impact of the built environment on child obesity, physical activity, sedentary behavior, and diet. Current government policy documents related to the built environment and child health were analyzed using the Comprehensive Analysis of Policy on Physical Activity framework. Ten Australian and 31 Western Australian government policy documents were identified. Most referred to the role of the built environment in supporting physical activity. Very few policies mentioned the built environment's role in reducing sedentary behaviors, supporting healthy eating, and addressing obesity. Few recognized the needs of children, and none mentioned children in policy development. Future government policy development should include the voices of children and child-specific built environment features. Inter-organizational policies with transparent implementation and evaluation plans are recommended.

A Review of the Role of Built Environment and Temperature in the Development of Childhood Obesity

The burden of obesity is rising globally and is studied widely, yet the evidence for the association of environmental factors (both built and natural) with childhood obesity remains inconsistent. A relation with temperature as a proxy for natural environmental factors for obesity has not been reviewed previously. The purpose of this review was to assimilate updated evidence on environmental factors of childhood obesity. Three databases, MEDLINE (Medical Literature Analysis and Retrieval System Online), Web of Science, and Cochrane, were searched for articles related to the effect of built environment and temperature on childhood obesity in 6-12-year-olds published in the last five years. Twelve studies were identified: four longitudinal and eight cross-sectional. The studies were appraised using the National Institute of Health Quality (NIH) Assessment Tool. A review of included studies showed that built environmental features like higher residential and population density, higher intersection density, more playgrounds, and all park features like the presence or availability of parks, high number of parks, proximity to parks, and an increased park land area, showed a protective association against childhood obesity while land use mix showed a promoting association for the development of childhood obesity. Inconclusive evidence was observed for other built environmental features. The search strategy did not retrieve any literature published in the past five years studying the association between temperature and the development of childhood obesity. Standardization of definitions of exposure and outcome measures is recommended. Further research studying the relationship between environmental temperature and the development of childhood obesity is recommended.

Point of Decision Design to Address Adolescent Overweight and Obesity

OBJECTIVES

This study aims to utilize the point of decision design framework to understand how, where, and why adolescents and families make decisions about diet and physical activity and to explore how modifications to the environment can help to promote healthier choices and reduce obesity.

BACKGROUND

Child and adolescent obesity is a critical public health problem. As environmental factors are a primary contributor, understanding the role of design in our surrounding environment highlights an important area of interdisciplinary study. Design strategies have been used successfully to increase stair use and reduce sedentary behavior and can be used to further promote healthier diet and activity choices among adolescents and families.

METHODS

We leveraged the human-centered design-thinking process through (1) qualitative interviews and survey instruments, (2) persona and prompt development, and (3) a design workshop with multidisciplinary stakeholders.

RESULTS

Five personas were developed from the qualitative data and used in a design-thinking workshop. During the workshop, participants generated 12 influential factors and nine points of decision which were used to generate 33 solutions spanning the design continuum (from information and policy design to the design of urban, architectural, and interior environments) aimed at improving nutrition and physical activity among adolescents. Additionally, a tool kit was prototyped, which includes interview guides, a persona framework, and a workshop facilitation guide.

CONCLUSIONS

Our novel process led to the generation of design solutions that can be implemented to expand and improve upon existing interventions for childhood obesity and create environments that encourage positive health outcomes.

The role of neighbourhood design in cycling activity during COVID-19: An exploration of the Melbourne experience

COVID-19 restrictions imposed significant changes on human mobility patterns, with some studies finding significant increases or decreases in cycling. However, to date there is little understanding on how the neighbourhood-level built environment influenced cycling behaviour during the COVID-19 restrictions. As different neighbourhood have different built environment characteristics, it is possible that cycling trends varied across different built environment settings. We aimed to answer this question by examining recreational cycling during different stages of lockdown in Melbourne, Australia. We compared self-reported recreational cycling frequency (weekly) data from 1344 respondents between pre-COVID and two different stages in lockdown. We tested whether the built environment of their residential neighbourhood and different sociodemographic characteristics influenced leisure cycling rates and whether the effect of these factors varied between different stages of COVID-19 restriction. We found that cycling declined significantly during the two stages of COVID-19 lockdown. Cycling infrastructure density and connectivity are two built environment factors that had a significant effect on limiting the decline in leisure cycling during the pandemic. Furthermore, men and younger people had higher cycling rates in comparison to other groups, suggesting that restrictions on indoor activities and travel limits were not enough to encourage women or older people to cycle more during the pandemic.

Perception of the Neighborhood Environment, Physical Activity by Domain and Sitting Time in Brazilian Adults

This study aimed to examine the association between the neighborhood environment and domain-specific physical activity and sitting time in Brazilian adults. This cross-sectional study included 1803 adults (53.7% women) from Brazil's five regions (North, Northeast, Midwest, Southeast and South). The perception of the environment was evaluated via a questionnaire. We considered seven indicators of the neighborhood environment: land use mix-diversity, land use mix-access, street connectivity, walking/cycling facilities, aesthetics, safety from traffic and safety from crime. Using the IPAQ, we evaluated physical activity (transport and leisure) and sitting time. Overall, land use mix-diversity (β = 3.22; 95% CI = 0.26, 6.19), land use mix-access (β = 2.27; 95% CI = 0.76, 3.79), and walking/cycling facilities (β = 2.42; 95% CI = 0.35, 4.49) were positively associated with leisure-time physical activity (min/week). On the other hand, only land use mix-diversity (β = 3.65; 95% CI = 0.63, 5.49) was positively associated with transport physical activity (min/week). No neighborhood environment indicator was associated with sitting time (min/day). Perception of the neighborhood environment was associated with physical activity (transport and leisure), while no significant associations occurred with sitting time among the five regions of Brazil. The neighborhood environment can be a viable component in the promotion of physical activity, but geographic diversity must be considered.

Built Environments And Child Health in WalEs and AuStralia (BEACHES): a study protocol

INTRODUCTION

Childhood obesity and physical inactivity are two of the most significant modifiable risk factors for the prevention of non-communicable diseases (NCDs). Yet, a third of children in Wales and Australia are overweight or obese, and only 20% of UK and Australian children are sufficiently active. The purpose of the Built Environments And Child Health in WalEs and AuStralia (BEACHES) study is to identify and understand how complex and interacting factors in the built environment influence modifiable risk factors for NCDs across childhood.

METHODS AND ANALYSIS

This is an observational study using data from five established cohorts from Wales and Australia: (1) Wales Electronic Cohort for Children; (2) Millennium Cohort Study; (3) PLAY Spaces and Environments for Children's Physical Activity study; (4) The ORIGINS Project; and (5) Growing Up in Australia: the Longitudinal Study of Australian Children. The study will incorporate a comprehensive suite of longitudinal quantitative data (surveys, anthropometry, accelerometry, and Geographic Information Systems data) to understand how the built environment influences children's modifiable risk factors for NCDs (body mass index, physical activity, sedentary behaviour and diet).

ETHICS AND DISSEMINATION

This study has received the following approvals: University of Western Australia Human Research Ethics Committee (2020/ET000353), Ramsay Human Research Ethics Committee (under review) and Swansea University Information Governance Review Panel (Project ID: 1001). Findings will be reported to the following: (1) funding bodies, research institutes and hospitals supporting the BEACHES project; (2) parents and children; (3) school management teams; (4) existing and new industry partner networks; (5) federal, state and local governments to inform policy; as well as (6) presented at local, national and international conferences; and (7) disseminated by peer-reviewed publications.

Neighborhood risk factors for sports and recreational injuries: a systematic review of studies applying multilevel modeling techniques

Background

Sports and recreational activities are the most commonly reported cause of injury-related emergency department (ED) visits among children and young adults in developed countries, yet studies about the effect of neighborhood environment on sports and recreational injuries (SRI) are very limited. The aim of this study was to systematically review studies that apply multilevel modeling approach in examining the relationships between SRI and neighborhood-level risk factors.

Data sources

A systematic search of peer reviewed English language articles was conducted in four electronic databases including PubMed (1992–2020), CINAHL (2000–2020), Sports Medicine and Education Index (1996–2020), and Web of Science (1991–2020).

Study selection

Selected studies were observational or experimental studies of people of all ages across the world that assessed neighborhood risk factors for SRI (or all injuries including SRI) using multilevel regression analysis.

Data synthesis

Nine studies—five cross-sectional, two prospective cohort, and two incidence studies—were selected out of a potential 1510. Six studies used secondary data and three used primary data. Only three studies examined SRI as the main or one of the main outcomes. These studies showed that neighborhood-level factors, such as higher socioeconomic context, lower street connectivity, and living or attending schools in urban communities, were associated with increased risk of SRI. Most studies did not provide a justification for the use of multilevel regression and the multilevel analytical procedure employed and quantities reported varied. The Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies (National Institutes of Health) was used to assess the quality or risk of bias of each study. Four quality assessment criteria out of 15 were met by all nine studies. The quality assessment ratings of the reviewed studies were not correlated with the quality of information reported for the multilevel models.

Conclusion

Findings from this review provide evidence that neighborhood-level factors, in addition to individual-level factors, should be taken into consideration when developing public health policies for injury prevention. Considering the limited numbers of studies that were identified by this systematic review, more multilevel studies are needed to strengthen this evidence in order to better inform SRI prevention policy decisions.

Associations between Children's Physical Activity and Neighborhood Environments Using GIS: A Secondary Analysis from a Systematic Scoping Review

Regular participation in physical activity is essential for children's physical, mental, and cognitive health. Neighborhood environments may be especially important for children who are more likely to spend time in the environment proximal to home. This article provides an update of evidence for associations between children's physical activity behaviors and objectively assessed environmental characteristics derived using geographical information system (GIS)-based approaches. A systematic scoping review yielded 36 relevant articles of varying study quality. Most studies were conducted in the USA. Findings highlight the need for neighborhoods that are well connected, have higher population densities, and have a variety of destinations in the proximal neighborhood to support children's physical activity behaviors. A shorter distance to school and safe traffic environments were significant factors in supporting children's active travel behaviors. Areas for improvement in the field include the consideration of neighborhood self-selection bias, including more diverse population groups, ground-truthing GIS databases, utilising data-driven approaches to derive environmental indices, and improving the temporal alignment of GIS datasets with behavioral outcomes.

Parental-perceived home and neighborhood environmental correlates of accelerometer-measured physical activity among school-going children in Uganda

The benefits of physical activity (PA) on children's health and well-being are well established. However, many children do not meet the PA recommendations, increasing their risk of being overweight, obese, and non-communicable diseases. Environmental characteristics of homes and neighborhoods may constrain a child's ability to engage in PA, but evidence is needed to inform country-specific interventions in understudied low-income countries. This study assessed the associations between parental-perceived home and neighbourhood, built environment characteristics, and moderate-to-vigorous physical activity (MVPA) among children in Kampala city, Uganda. In this cross-sectional study, data were obtained from 256 children (55.5% girls) aged between 10 and 12 years and their parents. Children's MVPA was measured using waist-worn ActiGraph accelerometers. The environments were assessed using a valid self-reported parent survey. Linear regression models with standard errors (clusters) were used to analyze the relationship between environmental variables and children's MVPA. Sex-specific relationships were assessed using sex-stratified models. Play equipment at home (β = -2.37, p <0.001; unexpected direction), residential density (β = 2.70, p<0.05), and crime safety (β = -5.29, p <0.05; unexpected direction) were associated with children's MVPA. The sex-specific analyses revealed more inconsistent patterns of results with a higher perception of land use mix associated with less MVPA in girls (irrespective of school type attended), and higher perceptions of sidewalk infrastructure (β = -12.01, p <0.05) and walking and cycling infrastructure (β = -14.72, p <0.05) associated with less MVPA in girls attending public schools only. A better perception of crime safety was associated with less MVPA among boys and girls attending private schools (β = -3.80, p <0.05). Few environmental characteristics were related to children's MVPA in Uganda, and findings were largely inconsistent, especially among girls. Future studies are needed to understand the ecological determinants of health-related PA behaviors among children in Uganda.

Enabling Better Physical Activity and Screen Time Behaviours for Adolescents from Middle Eastern Backgrounds: Semi-Structured Interviews with Parents

The unrelenting obesity pandemic in Middle Eastern (ME) adolescents living in Australia warrants culturally responsive and locally engineered interventions. Given the influence of parents on the lifestyle behaviours of adolescents, this qualitative study aimed to capture the opinions of ME parents on the barriers and enablers to sufficient physical activity and limiting screen time behaviours in adolescents. Semi-structured interviews were conducted with 26 ME parents (female) aged 35–59 years old, most of whom resided in lower socioeconomic areas (n = 19). A reflexive thematic analysis using the Theoretical Domains Framework and the Capability, Opportunity, Motivation-Behaviour model was performed for coding. Parents voiced confidence in their knowledge of the importance of physical activity and limiting screen time but were less optimistic in their ability to enable change in behaviours, especially for older adolescents without outside support. Despite adolescents having the necessary skills to engage in a wide array of sports, the parents admitted deep fears regarding the safety of the social environment and restricted their children’s independent mobility. Gender differences were noted, with parents reporting older girls expressing disinterest in sports and having limited physical opportunities to participate in sports at school. It may be that a community-based participatory framework is needed to improve physical activity opportunities and to address specific physical, social, and cultural barriers.

Association of Neighborhood Food Environment and Physical Activity Environment With Obesity: A Large-Scale Cross-Sectional Study of Fifth- to Ninth-Grade Children in Japan

Objective: This study examined the relationship between neighborhood food and physical activity environment, and obesity among elementary and junior high school students in Japan. Methods: The participants were fifth- to ninth-grade children (n=7277), who were attending municipal schools in Japan. Percent overweight (POW) was calculated using their age, gender, height, and weight, which were collected through a questionnaire. A POW of < 20% was considered non-obese, while ≥ 20% was considered obese. Furthermore, using a geographic information system, we investigated the density of convenience stores, fast-food stores, casual restaurants, supermarkets and department stores, parks, sports facilities, stations, and intersections in the school district. Additionally, from the census, we obtained information regarding the population density of the municipality where the participants' schools were located. Multiple logistic regression analysis was used to examine the relationship between obesity and food environment (the food environment model), between obesity and physical activity environment (the physical activity environment model), and among obesity, food, and physical activity environment (the food and physical activity environment model). Results: In the food environment model and the food and physical activity environment model, the density of convenience stores showed a significant positive association. In the physical activity environment model, the density of stations showed a significant negative association. Conclusion: This study's findings can contribute to the development of appropriate community interventions for improving children's health in Japan and similar areas.

Improving spatial data in health geographics: a practical approach for testing data to measure children's physical activity and food environments using Google Street View

Background

Geographic information systems (GIS) are often used to examine the association between both physical activity and nutrition environments, and children’s health. It is often assumed that geospatial datasets are accurate and complete. Furthermore, GIS datasets regularly lack metadata on the temporal specificity. Data is usually provided ‘as is’, and therefore may be unsuitable for retrospective or longitudinal studies of health outcomes. In this paper we outline a practical approach to both fill gaps in geospatial datasets, and to test their temporal validity. This approach is applied to both district council and open-source datasets in the Taranaki region of Aotearoa New Zealand.

Methods

We used the ‘streetview’ python script to download historic Google Street View (GSV) images taken between 2012 and 2016 across specific locations in the Taranaki region. Images were reviewed and relevant features were incorporated into GIS datasets.

Results

A total of 5166 coordinates with environmental features missing from council datasets were identified. The temporal validity of 402 (49%) environmental features was able to be confirmed from council dataset considered to be ‘complete’. A total of 664 (55%) food outlets were identified and temporally validated.

Conclusions

Our research indicates that geospatial datasets are not always complete or temporally valid. We have outlined an approach to test the sensitivity and specificity of GIS datasets using GSV images. A substantial number of features were identified, highlighting the limitations of many GIS datasets.

Home and Neighborhood Physical Activity Location Availability among African American Adolescent Girls Living in Low-Income, Urban Communities: Associations with Objectively Measured Physical Activity

Based on the ecological model of active living, the neighborhood environment may relate to individual physical activity (PA) behaviors. The purposes of this study were to (1) generate a replicable neighborhood-level physical activity location availability score (PALAS) from data variables associated with physical activity among adolescents and adults, and apply this score to Baltimore City, Maryland, and (2) determine if relationships exist between PA and PA location availability. Geographic information systems (GISs) were used to create the PALAS. Using linear regression models, we examined relations between objectively measured PA among low-income, urban, predominantly African American adolescent girls (n = 555, 2009-2012 data collection), and the PALAS rating of their neighborhood environment (neighborhood PALAS) and their home neighborhood area (PALAS variables/subcomponents within 0.25 miles of the home). A PALAS map of the study area was created, illustrating neighborhoods varying in availability and variety of PA locations. After adjusting for confounders, a higher neighborhood PALAS (β = 0.10, p = 0.041) and the presence of a recreation center in the home neighborhood area (β = 0.46, p = 0.011) were associated with more minutes per day spent in moderate to vigorous PA. Policy makers and stakeholders should consider increasing access to PA locations as a strategy to promote PA among adolescent girls.

Urban sprawl and childhood obesity

Urban sprawl is thought to be a risk factor for childhood obesity primarily because the physical environment it creates discourages children's physical activity while encouraging their sedentary behavior. However, there has not been any review on the association between urban sprawl and childhood obesity. This study filled this research gap by comprehensively reviewing literature focusing on associations between urban sprawl and weight-related behaviors and outcomes among children and adolescents. Only two longitudinal and three cross-sectional studies conducted in two countries were identified. Sample sizes ranged from 2324 to 129 781. Four studies used weight status, and only one study used both behaviors and weight status as outcome variables. All positive, negative, and non-significant associations were reported. This review could not identify a clear association between urban sprawl and childhood obesity. More longitudinal studies are needed for in-depth analyses on this important topic in more regions, which would be important not only for public health guidelines but also for research, practice, and policies in urban planning.

Neighborhood sidewalk access and childhood obesity

The lack of access to sidewalks is a barrier for physical activity (PA) and may be a risk factor for childhood obesity. However, previous studies reported mixed findings and the association between sidewalk accessibility and childhood obesity remains unclear. This study systematically examined the evidence on the association between sidewalk accessibility and childhood obesity. PubMed, Cochrane Library, and Web of Science were searched for relevant articles (published before 1 January 2019) that reported on the association between neighborhood sidewalk access and weight-related behaviors and outcomes in children. Seventeen studies conducted in five countries were included. Ten studies used objective measure of access to sidewalks, seven studies measured children's height and weight, and seven studies objectively measured the PA or sedentary behaviors. Ten studies reported on the association of better access to sidewalks with increased PA (β ranging from 0.032 to 2.159; p < 0.05), reduced sedentary behaviors (β ranging from -0.19 to -0.14; p < 0.05), lower body mass index (BMI) (β ranging from -0.261 to -0.144; p < 0.001), or obesity risks (OR ranging from 1.02 to 1.32; p < 0.05); while the remaining seven studies did not report a desirable obesity-sidewalk association. Our findings support the hypothesis that higher sidewalk accessibility is associated with higher PA levels, lower BMI, and obesity risks. Efforts in building healthy environments, including health-promoting city planning, can help minimize the growing obesity epidemic and promote public health.

Neighbourhood residential density and childhood obesity

Residential density is considered an important attribute of the built environment that may be relevant to childhood obesity. However, findings remain inconclusive, and there are no reviews yet on the association between residential density and childhood obesity. This study aimed to systematically review the associations between residential density and weight-related behaviours and outcomes. A comprehensive literature search was conducted using the Cochrane Library, PubMed and Web of Science for articles published before 1 January 2019. A total of 35 studies conducted in 14 countries were identified, including 33 cross-sectional studies, one longitudinal study and one containing both study designs. Residential density was measured by Geographic Information Systems in 28 studies within a varied radius from 0.25 to 2 km around the individual residence. Our study found a general positive association between residential density and physical activity (PA); no significant associations were observed. This study provided evidence for a supportive role of residential density in promoting PA among children. However, it remained difficult to draw a conclusion between residential density and childhood obesity. Future longitudinal studies are warranted to confirm this association.

Neighbourhood speed limit and childhood obesity

As an important factor for neighbourhood walkability, the speed limit in the neighbourhood may influence children's physical activity (PA) outdoors, especially active transport, and further their weight status. This review aimed to systematically evaluate the association between neighbourhood speed limit and obesity-related behaviours and outcomes among children and adolescents. PubMed, Embase and Web of Science were systematically searched for relevant studies published from the inception of the database to 1 January 2019. Sixteen studies were included, with 13 cross-sectional studies and three longitudinal studies. Speed limit was measured as the percentage/number of high-speed roads, perception of safe driving speed, perception of speeding and use of traffic-calming tools in the neighbourhood. Eleven studies measured the use of active transport as the outcome of interest, and seven studies measured PA directly. Eleven studies revealed an association between a lower speed limit and increased PA, whereas one study showed a negative association, and three studies reported non-significant associations. Only one study associated speed limit with weight status, which reported a non-significant association. This review generally supported a negative association between speed limit and PA among children and adolescents. More studies are needed to examine their causality, as well as the association between speed limit and weight status, in order to increase the impact of this research area on public health policy making.

Association between neighborhood aesthetics and childhood obesity

The lack of neighbourhood aesthetics (e.g. public art and well-maintained properties) may reduce walkability in the neighbourhood and increase the risk of childhood obesity. In this study, a literature search was conducted in the Cochrane Library, PubMed and Web of Science for articles published before January 1, 2019 to analyse the associations between neighbourhood aesthetics and weight-related behaviours and outcomes among children and adolescents aged <18. One cohort study and 24 cross-sectional studies, conducted in 10 countries with a median sample size of 1124 were identified. Neighbourhood aesthetics was more commonly assessed by self-reported or parent-reported perceptions than objective measurements. Eighteen of the 25 included studies analysed physical activity (PA) as the outcome of interests, eight studies analysed active transport to school (ATS), and eight studies analysed weight status, including body mass index and overweight/obesity status. About two-thirds of studies reported non-significant associations when using PA and weight status as outcomes, and half of studies showed that neighbourhood aesthetics is associated with increased use of ATS. The rest of the studies reported mixed findings with slightly more studies showing neighbourhood aesthetics may promote PA or reduce weight. Better designed studies are necessary to achieve a robust understanding of this epidemiological relationship in the future.

Access to bike lanes and childhood obesity: A systematic review and meta-analysis

The lack of bike lane access has been a proven risk factor for childhood obesity due to its role in discouraging healthy lifestyles. However, there has not been a systematic review of this important association in the existing literature. This study aims to fill this gap. A literature search was conducted in the Cochrane Library, PubMed, Embase, and Web of Science for studies published from 1 January 2019 onwards that examined the association between bike lane access and weight-related behaviours and outcomes among children aged <18 years. A total of 21 studies were included in this systematic review. Among them, most of the studies showed that bike lane access was significantly associated with children and adolescents' physical activity (PA), whereas only two studies showed a negative association. Meta-analysis also supported these findings and showed that bike lane access was significantly associated with children and adolescents' PA (odds ratio [OR] = 1.57, 95% confidence interval [CI]: 1.37-1.81). Additionally, we reviewed how bike lane characteristics and microenvironment variables such as children and adolescents' choice of bicycle travel mode, the degree of separation of cycle path, cycle path unevenness, and street maintenance were associated with adolescents' preferences and intention to cycle. This systematic review and meta-analysis strongly suggests that bike lane access is associated with children and adolescents' PA. Nonetheless, it was difficult to draw a conclusion on the association between bike lane access and weight-related outcomes.

Street connectivity, physical activity, and childhood obesity: A systematic review and meta-analysis

Street connectivity, as a neighbourhood built environmental factor, may affect individual physical activity (PA) and subsequently weight status. However, these associations remain inconclusive. This study aimed to systematically review the association between street connectivity and childhood obesity. A literature search was conducted in the Cochrane Library, PubMed, and Web of Science for articles published before January 1, 2019. All original studies that investigated the association between street connectivity and weight-related behaviours or outcomes among children and adolescents were included. Forty-seven articles were identified, including eight longitudinal and 41 cross-sectional studies conducted in eight countries. The sample size ranged from 88 to 46 813. Street intersection density (SID), measured by Geographic Information Systems in 36 studies and reported in 13 studies, was the main indicator used to represent street connectivity. Forty-four studies examined the association between SID and weight-related behaviours, including overall PA (n = 15), moderate-to-vigorous PA (n = 13), active transport (n = 12), dog walking (n = 1), walking (n = 1), sedentary behaviours (n = 2), and TV viewing (n = 1). Fifteen studies focused on the association between SID and weight-related outcomes. Overall, evidence from this systematic review and meta-analyses suggested a positive association between street connectivity and PA. However, it was difficult to draw a conclusion on the association between street connectivity and BMI. More longitudinal evidence is needed to confirm the causal association between street connectivity and weight status.

Association between access to full-service restaurants and childhood obesity

The lack of access to full-service restaurants (FSRs) is generally thought to be a risk factor for childhood obesity, as it could discourage healthful eating-out behaviours while increasing the exposure to unhealthful food venues as "compensatory" options. However, the association between FSR access and childhood obesity has not been comprehensively reviewed previously. A literature search was conducted on PubMed and Web of Science for articles published before 1 January 2019 that examined the association between FSR access and weight-related behaviours and outcomes among children and adolescents. Eighteen studies conducted in three countries were identified, published from 2006 to 2018 with a median sample size of 2352 (ranging from 323 to 529 367). Findings were mixed among these 18 studies that reported on the association between access to FSRs and weight-related outcomes. Our meta-analyses showed that there were no significant associations of FSR access with the level of body mass index (BMI) and the BMI z-score among children. Also, there was no apparent evidence on the association between FSR access and the risk of overweight/obesity. Our results need to be interpreted with caution, considering the menu quality of FSRs and heterogeneity of eligible studies in this meta-analysis. Well-designed epidemiologic studies are warranted to further elaborate on the potential association between FSR access and children's weight status.

Natural environment and childhood obesity: A systematic review

The associations between built and food environments and childhood obesity have been studied extensively. However, the association between the natural environment and childhood obesity has received too little scholarly attention. This study reviewed the literature published before 1 January 2019, which described associations between a full range of natural environmental factors (e.g., rainfall, temperature, sunlight, natural disasters, flood and drought) and weight-related behaviours and childhood obesity. Five cross-sectional studies and one longitudinal study were identified. Measures of natural environmental factors varied across six included studies, falling into five broad categories: weather conditions, altitude, natural disaster risk, air quality and day length. It was found that temperature was a significant weather indicator in most included studies and was associated with a reduction of daily physical activity. Children living in high-altitude areas were more likely to be shorter and heavier than their counterparts in low-altitude areas. Findings of this study will contribute to helping multiple stakeholders, including policy makers and urban planners, and formulate health policies and interventions to mitigate the detrimental impact of the natural environment on childhood obesity. More longitudinal studies should be designed to confirm these effects and explore the potential health effects of more natural environmental factors.

Obesity and activity patterns before and during COVID-19 lockdown among youths in China

This study aim to assess changes in obesity and activity patterns among youths in China during the COVID-19 lockdown. We used the COVID-19 Impact on lifestyle change survey (COINLICS), a national retrospective survey distributed via social media platforms in early May 2020 where more than 10 000 youth participants in China have voluntarily reported their basic sociodemographic information, weight status, and routine lifestyles in the months before and during COVID-19 lockdown. The extended IOTF and WHO standards were used to define overweight and obesity of the participants. We used paired t-tests or χ² tests and non-parametric methods to evaluate the significance of differences in weight-related outcomes and lifestyles across education levels, between sexes, and before and during COVID-19 lockdown. The mean body mass index of all participating youths has significantly increased (21.8-22.6) and in all education subgroups during COVID-19 lockdown. Increases also occurred in the prevalence of overweight/obesity (21.3%-25.1%, P < .001) and obesity (10.5% to 12.9%, P < .001) in overall youths, especially in high school and undergraduate students. Their activity patterns had also significantly changed, including the decreased frequency of engaging in active transport, moderate-/vigorous-intensity housework, leisure-time moderate-/vigorous-intensity physical activity, and leisure-time walking, and the increased sedentary, sleeping, and screen time. Our findings would inform policy-makers and clinical practitioners of these changes in time, for better policy making and clinical practice. School administrators should also be informed of these changes, so in-class and/or extracurricular physical activity programs could be designed to counteract them.

A large prospective investigation of outdoor light at night and obesity in the NIH-AARP Diet and Health Study

BACKGROUND

Research has suggested that artificial light at night (LAN) may disrupt circadian rhythms, sleep, and contribute to the development of obesity. However, almost all previous studies are cross-sectional, thus, there is a need for prospective investigations of the association between LAN and obesity risk. The goal of our current study was to examine the association between baseline LAN and the development of obesity over follow-up in a large cohort of American adults.

METHODS

The study included a sample of 239,781 men and women (aged 50-71) from the NIH-AARP Diet and Health Study who were not obese at baseline (1995-1996). We used multiple logistic regression to examine whether LAN at baseline was associated with the odds of developing obesity at follow-up (2004-2006). Outdoor LAN exposure was estimated from satellite imagery and obesity was measured based on self-reported weight and height.

RESULTS

We found that higher outdoor LAN at baseline was associated with higher odds of developing obesity over 10 years. Compared with the lowest quintile of LAN, the highest quintile was associated with 12% and 19% higher odds of developing obesity at follow-up in men (OR (95% CI) = 1.12 (1.00, 1.250)) and women (1.19 (1.04, 1.36)), respectively.

CONCLUSIONS

Our findings suggest that high LAN exposure could predict a higher risk of developing obesity in middle-to-older aged American adults.

Health and the built environment in United States cities: measuring associations using Google Street View-derived indicators of the built environment

BACKGROUND

The built environment is a structural determinant of health and has been shown to influence health expenditures, behaviors, and outcomes. Traditional methods of assessing built environment characteristics are time-consuming and difficult to combine or compare. Google Street View (GSV) images represent a large, publicly available data source that can be used to create indicators of characteristics of the physical environment with machine learning techniques. The aim of this study is to use GSV images to measure the association of built environment features with health-related behaviors and outcomes at the census tract level.

METHODS

We used computer vision techniques to derive built environment indicators from approximately 31 million GSV images at 7.8 million intersections. Associations between derived indicators and health-related behaviors and outcomes on the census-tract level were assessed using multivariate regression models, controlling for demographic factors and socioeconomic position. Statistical significance was assessed at the α = 0.05 level.

RESULTS

Single lane roads were associated with increased diabetes and obesity, while non-single-family home buildings were associated with decreased obesity, diabetes and inactivity. Street greenness was associated with decreased prevalence of physical and mental distress, as well as decreased binge drinking, but with increased obesity. Socioeconomic disadvantage was negatively associated with binge drinking prevalence and positively associated with all other health-related behaviors and outcomes.

CONCLUSIONS

Structural determinants of health such as the built environment can influence population health. Our study suggests that higher levels of urban development have mixed effects on health and adds further evidence that socioeconomic distress has adverse impacts on multiple physical and mental health outcomes.