Public transit generates new physical activity: Evidence from individual GPS and accelerometer data before and after light rail construction in a neighborhood of Salt Lake City, Utah, USA

Public transit stop density is associated with walking for exercise among a national sample of older adults

BACKGROUND

Walking is the primary and preferred mode of exercise for older adults. Walking to and from public transit stops may support older adults in achieving exercise goals. This study examined whether density of neighborhood public transit stops was associated with walking for exercise among older adults.

METHODS

2018 National Health and Aging Trends Study (NHATS) data were linked with the 2018 National Neighborhood Data Archive, which reported density of public transit stops (stops/mile2) within participants' neighborhood, defined using census tract boundaries. Walking for exercise in the last month was self-reported. The extent to which self-reported public transit use mediated the relationship between density of neighborhood public transit stops and walking for exercise was examined. Covariates included sociodemographic characteristics, economic status, disability status, and neighborhood attributes. National estimates were calculated using NHATS analytic survey weights.

RESULTS

Among 4,836 respondents with complete data, 39.7% lived in a census tract with at least one neighborhood public transit stop and 8.5% were public transit users. The odds of walking for exercise were 32% higher (OR = 1.32; 95% confidence interval: 1.08, 1.61) among respondents living in a neighborhood with > 10 transit stops per mile compared to living in a neighborhood without any public transit stops documented. Self-reported public transit use mediated 24% of the association between density of neighborhood public transit stops and walking for exercise.

CONCLUSIONS

Density of neighborhood public transit stops was associated with walking for exercise, with a substantial portion of the association mediated by self-reported public transit use. Increasing public transit stop availability within neighborhoods may contribute to active aging among older adults.

Examining the impacts of public transit on healthy aging through a natural experiment: study protocols and lessons learned from the Active El Paso project

This paper describes protocols and experiences from a seven-year natural-experiment study in El Paso, Texas, a border city of predominantly Latino/Hispanic population. The study focuses on how Bus Rapid Transit (BRT) impacts physical activity and thus plays a role in alleviating obesity and related chronic diseases that impact healthy aging. Our protocols describe a longitudinal and case-comparison study, which compared residents exposed to new BRT stations with those who were not. This paper also introduces lessons and experiences to overcome the following challenges: delays in the BRT opening (the main intervention), the COVID-19 pandemic, methodological challenges, participant recruitment and retention, and predatory survey takers. Our transdisciplinary approach was pivotal in addressing these challenges. We also proposed and tested multi-level intervention strategies to reduce modifiable barriers to transit use. Our most important takeaway for researchers, practitioners, and policy makers is the importance of being flexible and ready to adapt to new circumstances. Future natural-experiment researchers need to become more versatile in an increasingly volatile and uncertain world.

Trading-Off Transit and Non-Transit Physical Activity among Older People: Evidence from Longitudinal Accelerometer Data of a Natural Experiment Study

This study used a natural experiment of a new metro line in Hong Kong to examine trade-offs between transit-related and non-transit-related physical activity (PA) among 104 older people (aged ≥ 65 years) based on longitudinal accelerometer data that distinguished transit-related and non-transit-related PA. Difference-in-difference (DID) analysis compared PA changes between treatment and control groups. We found that new metro stations have trade-off effects between transit and non-transit PA. After opening metro stations, transit-related PA increased by 12 min per day on average, but non-transit-related PA decreased by 18 min per day. In addition, the proportion of time spent in transit-related PA increased by 6%. The results suggested that new metro stations could generate transit-related PA, but it might shift from non-transit-related PA among older people. Our findings revealed trade-off effects of public transit interventions and have significant implications for transport and healthy ageing studies.

Objectively measuring the association between the built environment and physical activity: a systematic review and reporting framework

Background

Objective measures of built environment and physical activity provide the opportunity to directly compare their relationship across different populations and spatial contexts. This systematic review synthesises the current body of knowledge and knowledge gaps around the impact of objectively measured built environment metrics on physical activity levels in adults (≥ 18 years). Additionally, this review aims to address the need for improved quality of methodological reporting to evaluate studies and improve inter-study comparability though the creation of a reporting framework.

Methods

A systematic search of the literature was conducted following the PRISMA guidelines. After abstract and full-text screening, 94 studies were included in the final review. Results were synthesised using an association matrix to show overall association between built environment and physical activity variables. Finally, the new PERFORM (’Physical and Environmental Reporting Framework for Objectively Recorded Measures’) checklist was created and applied to the included studies rating them on their reporting quality across four key areas: study design and characteristics, built environment exposures, physical activity metrics, and the association between built environment and physical activity.

Results

Studies came from 21 countries and ranged from two days to six years in duration. Accelerometers and using geographic information system (GIS) to define the spatial extent of exposure around a pre-defined geocoded location were the most popular tools to capture physical activity and built environment respectively. Ethnicity and socio-economic status of participants were generally poorly reported. Moderate-to-vigorous physical activity (MVPA) was the most common metric of physical activity used followed by walking. Commonly investigated elements of the built environment included walkability, access to parks and green space. Areas where there was a strong body of evidence for a positive or negative association between the built environment and physical activity were identified. The new PERFORM checklist was devised and poorly reported areas identified, included poor reporting of built environment data sources and poor justification of method choice.

Conclusions

This systematic review highlights key gaps in studies objectively measuring the built environment and physical activity both in terms of the breadth and quality of reporting. Broadening the variety measures of the built environment and physical activity across different demographic groups and spatial areas will grow the body and quality of evidence around built environment effect on activity behaviour. Whilst following the PERFORM reporting guidance will ensure the high quality, reproducibility, and comparability of future research.

The TROLLEY Study: assessing travel, health, and equity impacts of a new light rail transit investment during the COVID-19 pandemic

BACKGROUND

The COVID-19 pandemic disrupted life in extraordinary ways impacting health and daily mobility. Public transit provides a strategy to improve individual and population health through increased active travel and reduced vehicle dependency, while ensuring equitable access to jobs, healthcare, education, and mitigating climate change. However, health safety concerns during the COVID-19 pandemic eroded ridership, which could have longstanding negative consequences. Research is needed to understand how mobility and health change as the pandemic recedes and how transit investments impact health and equity outcomes.

METHODS

The TROLLEY (TRansit Opportunities for HeaLth, Livability, Exercise and EquitY) study will prospectively investigate a diverse cohort of university employees after the opening of a new light rail transit (LRT) line and the easing of campus COVID-19 restrictions. Participants are current staff who live either < 1 mile, 1-2 miles, or  > 2 miles from LRT, with equal distribution across economic and racial/ethnic strata. The primary aim is to assess change in physical activity, travel mode, and vehicle miles travelled using accelerometer and GPS devices. Equity outcomes include household transportation and health-related expenditures. Change in health outcomes, including depressive symptoms, stress, quality of life, body mass index and behavior change constructs related to transit use will be assessed via self-report. Pre-pandemic variables will be retrospectively collected. Participants will be measured at 3 times over 2 years of follow up. Longitudinal changes in outcomes will be assessed using multilevel mixed effects models. Analyses will evaluate whether proximity to LRT, sociodemographic, and environmental factors modify change in outcomes over time.

DISCUSSION

The TROLLEY study will utilize rigorous methods to advance our understanding of health, well-being, and equity-oriented outcomes of new LRT infrastructure through the COVID-19 recovery period, in a sample of demographically diverse adult workers whose employment location is accessed by new transit. Results will inform land use, transportation and health investments, and workplace interventions. Findings have the potential to elevate LRT as a public health priority and provide insight on how to ensure public transit meets the needs of vulnerable users and is more resilient in the face of future health pandemics.

TRIAL REGISTRATION

The TROLLEY study was registered at ClinicalTrials.gov ( NCT04940481 ) June 17, 2021, and OSF Registries ( https://doi.org/10.17605/OSF.IO/PGEHU ) June 24, 2021, prior to participant enrollment.

Walking for transportation in large Latin American cities: walking-only trips and total walking events and their sociodemographic correlates

Walking for transportation is a common and accessible means of achieving recommended physical activity levels, while providing important social and environmental co-benefits. Even though walking in rapidly growing urban areas has become especially challenging given the increasing dependence on motorised transportation, walking remains a major mode of transportation in Latin American cities. In this paper we aimed to quantify self-reported walking for transportation in Mexico City, Bogota, Santiago de Chile, Sao Paulo, and Buenos Aires, by identifying both walking trips that are conducted entirely on foot and walking events involved in trips mainly conducted on other means of transportation (e.g. private vehicle, public transit) among individuals ≥5-years old. We show how walking-only trips account for approximately 30% trips in the analysed cities, and we evidence how the pedestrian dimension of mobility is largely underestimated if walking that is incidental to other transportation modes is not accounted for: when considering all walking events, we observed an increase between 73% and 217% in daily walking time. As a result, we estimated that between 19% and 25% of residents in these cities meet the WHO physical activity guidelines solely from walking for transportation. The results of the study also suggest that the promotion of public transportation in large Latin American cities can especially help certain population groups achieve the daily recommended levels of physical activity, while among low-income groups accessibility and safety seem to be the key challenges to be addressed.

Is mode of transport to work associated with mortality in the working-age population? Repeated census-cohort studies in New Zealand, 1996, 2001 and 2006

BACKGROUND

Increasing active transport is proposed as a means to address both health and environmental issues. However, the associations between specific modes, such as cycling, walking and public transport, and health outcomes remain unclear. We examined the association between mode of travel to work and mortality.

METHODS

Cohort studies of the entire New Zealand working population were created using 1996, 2001 and 2006 censuses linked to mortality data. Mode of travel to work was that reported on census day, and causes of death examined were ischaemic heart disease and injury. Main analyses were Poisson regression models adjusted for socio-demographics. Sensitivity analyses included: additional adjustment for smoking in the 1996 and 2006 cohorts, and bias analysis about non-differential misclassification of cycling vs car use.

RESULTS

Walking (5%) and cycling (3%) to work were uncommon. Compared with people reporting using motor vehicles to travel to work, those cycling had a reduced all-cause mortality (ACM) in the socio-demographic adjusted models RR 0.87 (0.77-0.98). Those walking (0.97, 0.90-1.04) and taking public transport (0.96, 0.88-1.05) had no substantive difference in ACM. No mode of transport was associated with detectable statistically significant reductions in cause-specific mortality. Sensitivity analyses found weaker associations when adjusting for smoking and stronger associations correcting for likely non-differential misclassification of cycling.

CONCLUSIONS

This large cohort study supports an association between cycling to work and reduced ACM, but found no association for walking or public-transport use and imprecise cause-specific mortality patterns.

Implementation of IoT Framework with Data Analysis Using Deep Learning Methods for Occupancy Prediction in a Building

Many countries worldwide face challenges in controlling building incidence prevention measures for fire disasters. The most critical issues are the localization, identification, detection of the room occupant. Internet of Things (IoT) along with machine learning proved the increase of the smartness of the building by providing real-time data acquisition using sensors and actuators for prediction mechanisms. This paper proposes the implementation of an IoT framework to capture indoor environmental parameters for occupancy multivariate time-series data. The application of the Long Short Term Memory (LSTM) Deep Learning algorithm is used to infer the knowledge of the presence of human beings. An experiment is conducted in an office room using multivariate time-series as predictors in the regression forecasting problem. The results obtained demonstrate that with the developed system it is possible to obtain, process, and store environmental information. The information collected was applied to the LSTM algorithm and compared with other machine learning algorithms. The compared algorithms are Support Vector Machine, Naïve Bayes Network, and Multilayer Perceptron Feed-Forward Network. The outcomes based on the parametric calibrations demonstrate that LSTM performs better in the context of the proposed application.

Physical Activity across Retirement Transition by Occupation and Mode of Commute

Supplemental digital content is available in the text.

Purpose

Retirement induces changes in the composition of daily physical activity. Our aim was to examine changes in accelerometer-measured physical activity around transition to statutory retirement among men and women by occupational category and by preretirement modes of commuting.

Methods

We included 562 workers (mean [SD] age, 63.3 [1.1] yr; 85% women) from the Finnish Retirement and Aging study. The participants wore an accelerometer on their nondominant wrist for 1 wk before and 1 wk after retirement, with 1 yr between the measurements. We compared mean daily activity counts before and after retirement between manual and nonmanual occupations by gender and by preretirement commuting mode using linear models with generalized estimating equations.

Results

Before retirement, women were more active than men (2550 (95% confidence interval, 2500–2590) vs 2060 (1970–2140) mean daily activity counts), with the most active group being women in manual occupations. After retirement, physical activity decreased by 3.9% among women and increased, albeit nonsignificantly, by 3.1% in men. The decrease was most pronounced among women in manual and increase among men in nonmanual occupations. After retirement, women remained more active than men (2450 (95% confidence interval 2390–2500) vs 2120 (2010–2230) counts). Active commuting, especially cycling, before retirement was associated with higher physical activity both before and after retirement, and these people also maintained their total activity lever better than did those who commuted by public transportation.

Conclusions

Although women in manual occupations decreased and men in nonmanual occupations increased their activity after retirement, women were more active than men both before and after retirement. Those who engaged in active commuting before retirement maintained their activity level also after retirement.

Transit environments for physical activity: Relationship between micro-scale built environment features surrounding light rail stations and ridership in Houston, Texas

INTRODUCTION

Health professionals promote transport-related physical activity because travelers oftentimes walk or bike to and from transit stops or stations. Although previous studies have examined the associations between macro-scale built environment features surrounding light rail transit (LRT) stations (e.g., density) and LRT ridership, this study examined the associations between numerous micro-scale features (e.g., street-level noise pollution) and ridership.

METHODS

This analysis originated from the Houston Travel-Related Activity in Neighborhoods (TRAIN) Study, a project evaluating how an LRT extension impacted adult physical activity in Houston, Texas. In 2014, researchers used the Analytic Audit Tool to quantify 58 micro-scale built environment features within six categories: Land Use Environment, Transportation Environment, Facilities, Aesthetics, Signage, and Social Environment. Feature data were obtained from 590 street segments within 0.25 miles of 22 LRT stations. For each station, separate composite indices were created per category by averaging the computed feature scores (1-7) within each category, with higher scores signifying more physical activity-promoting features. Station-level LRT ridership data were obtained from monthly ridership reports for the 12 months following station opening. Linear mixed models were constructed to examine the associations of the six built environment categories with ridership, adjusting for season, weekday vs. weekend day, and station as a random intercept.

RESULTS

Holding all other variables constant, every one-unit increase in composite index scores for Transportation Environment and Social Environment was associated with an increase in daily ridership by 425 and 488 riders, respectively (p < 0.05). Every one-unit increase in composite index score for Signage was associated with a decrease of 722 riders daily (p < 0.05). The relations of Land Use Environment, Facilities, and Aesthetics with ridership were statistically null (p > 0.05).

CONCLUSIONS

Enhancements to the Transportation Environment and Social Environment may slightly increase overall LRT ridership, and consequently, utilitarian physical activity.

National and metropolitan trends in public transit use, transit-related walking, and ridesharing between 2009 and 2017

Introduction

Walking is a common form of physical activity and is the most frequent way to access public transit. On-going changes in the US transportation system are occurring, notably increases in smartphone application-based ridesharing. The goal of this research is to assess whether increasing use of ridesharing was associated with a change in transit-related walking. This is important to both public health and transportation, as it can inform changes in active transportation which promotes both physical activity and transit use.

Methods

We examined the association between change in transit use, transit-related walking, and ridesharing nationally and for selected metropolitan areas using the 2009 and 2017 National Household Travel Survey (≥18 years; n = 263,572 and n = 230,592, respectively). Analyses were conducted in 2019. Covariates included sex, age, race/ethnicity, education, employment, work from home, household size, number of vehicles, population density, Census region, metro area size and heavy rail transit category and season.

Results

The national prevalence of transit use in the past month in 2009 was 16.9% (95% CI: 16.4%-17.4%) and in 2017 was 16.1% (15.6%-16.6%), a significant decrease (p < 0.02). The prevalence of daily transit-related walking in 2009 was 4.2% (4.0%-4.4%) and in 2017 was 4.4% (4.2%-4.6%; p = 0.22). The prevalence of daily taxi use in 2009 was 0.5% (0.4%-0.6%) and taxi/rideshare in 2017 was 1.1% (1.0%-1.2%), a significant increase (p < 0.0001). The relationships remained after covariate adjustment. Finally, there was not a significant change in transit-related walking or interaction between year and taxi/rideshare use after additional adjustment for taxi/rideshare. Changes in transit-related walking in metros were largely not significant, whereas increases in taxi/rideshare were largely significant.

Conclusions

Results suggest that increased use of ridesharing may not be linked with changes in transit-related walking. Continued surveillance of travel mode prevalence is required to track potential reductions in population-level physical activity with technology-related changes in travel.

A systematic review of the evolution of GPS use in active living research: A state of the evidence for research, policy, and practice

This is the first systematic review to comprehensively capture Global Positioning Systems' (GPS) utilization in active living research by investigating the influence of physical contexts and social environment on all intensities of physical activity and sedentary behavior among all age groups. An extensive search of peer-reviewed literature was conducted using six databases. Out of 2026 articles identified, 129 studies met the inclusion criteria. After describing the evolution of GPS use across four themes (study designs and methods, physical contexts and social environment, active transportation, and behaviors), evidence-based recommendations for active living research, policy, and practice were generated.

Case-comparison study protocol for gauging effects of neighbourhood trends and sickness: examining the perceptions of transit-Induced gentrification in Prince George's County

INTRODUCTION

Impoverished neighbourhoods and communities of colour often bear the brunt of unintended transit-oriented development (TOD) impacts. These impacts have been known to come in the form of transit-induced gentrification (TIG), a socioeconomic by-product of TOD defined as a phenomenon that occurs when the provision of transit service, particularly light rail transit (LRT), 'up-scales' nearby neighbourhood(s) and displaces existing residents. Consequently, TIG or even the perception of TIG can impact health outcomes (eg, anxiety) and social determinants of health (SDOH) (eg, crime).

METHODS/ANALYSIS

In 2022, the purple line (PL), a 16.2 mile LRT line, is opening in Prince George's County, Maryland, a suburb of Washington, DC, comprised of over 80% African American and Hispanic residents. By taking advantage of this natural experiment, we are proposing the GENTS (Gauging Effects of Neighborhood Trends and Sickness: Examining the Perceptions of Transit-Induced Gentrification in Prince George's County) Study in order to evaluate perceived TIG and associated health outcome and SDOH changes, at two points in time, among Prince George's County adults in a prospective case-comparison design during the pre-PL LRT period. Descriptive analysis and latent growth curve modelling will be used to examine these changes over time.

ETHICS AND DISSEMINATION

Ethics approval has been granted by the University of Maryland Institutional Review Board. The GENTS Study will identify temporal changes in perceived TIG, health outcomes and SDOH among case and comparison residents before the completion and operation of the PL LRT, an under researched period of TOD. The dissemination of GENTS Study findings will be able to address research questions and policy issues that are specifically tailored to PG County while also providing more effective procedural solutions for other regions undergoing TOD and TIG risks.

Impact of Built Environments on Body Weight (the Moving to Health Study): Protocol for a Retrospective Longitudinal Observational Study

BACKGROUND

Studies assessing the impact of built environments on body weight are often limited by modest power to detect residential effects that are small for individuals but may nonetheless comprise large attributable risks.

OBJECTIVE

We used data extracted from electronic health records to construct a large retrospective cohort of patients. This cohort will be used to explore both the impact of moving between environments and the long-term impact of changing neighborhood environments.

METHODS

We identified members with at least 12 months of Kaiser Permanente Washington (KPWA) membership and at least one weight measurement in their records during a period between January 2005 and April 2017 in which they lived in King County, Washington. Information on member demographics, address history, diagnoses, and clinical visits data (including weight) was extracted. This paper describes the characteristics of the adult (aged 18-89 years) cohort constructed from these data.

RESULTS

We identified 229,755 adults representing nearly 1.2 million person-years of follow-up. The mean age at baseline was 45 years, and 58.0% (133,326/229,755) were female. Nearly one-fourth of people (55,150/229,755) moved within King County at least once during the follow-up, representing 84,698 total moves. Members tended to move to new neighborhoods matching their origin neighborhoods on residential density and property values.

CONCLUSIONS

Data were available in the KPWA database to construct a very large cohort based in King County, Washington. Future analyses will directly examine associations between neighborhood conditions and longitudinal changes in body weight and diabetes as well as other health conditions.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/16787.

Using Accelerometer and GPS Data for Real-Life Physical Activity Type Detection

This paper aims to examine the role of global positioning system (GPS) sensor data in real-life physical activity (PA) type detection. Thirty-three young participants wore devices including GPS and accelerometer sensors on five body positions and performed daily PAs in two protocols, namely semi-structured and real-life. One general random forest (RF) model integrating data from all sensors and five individual RF models using data from each sensor position were trained using semi-structured (Scenario 1) and combined (semi-structured + real-life) data (Scenario 2). The results showed that in general, adding GPS features (speed and elevation difference) to accelerometer data improves classification performance particularly for detecting non-level and level walking. Assessing the transferability of the models on real-life data showed that models from Scenario 2 are strongly transferable, particularly when adding GPS data to the training data. Comparing individual models indicated that knee-models provide comparable classification performance (above 80%) to general models in both scenarios. In conclusion, adding GPS data improves real-life PA type classification performance if combined data are used for training the model. Moreover, the knee-model provides the minimal device configuration with reliable accuracy for detecting real-life PA types.

Intention to use light-rail transit in Houston, Texas, United States: Findings from the Travel-Related Activity in Neighborhoods study

Using data from the Houston Travel-Related Activity in Neighborhoods (TRAIN) study, this study examined how various factors affect whether individuals intend to use newly opened light-rail transit (LRT) lines in Houston. The Houston TRAIN study is a natural experiment on the effect of new LRT lines on both transit use and physical activity. A mixed binary logit model was developed based on a dichotomous dependent variable and rich set of variables, including sociodemographic factors, health status, travel behavior and technology, and attitudes and perceptions. The mixed model also allowed accounting for the unobserved heterogeneity across individuals in their sensitivity to observed variables. The results indicated the important role of various factors influencing the decision on intent to use the new LRT lines. In general, demographics mattered but to a lower extent than psychological or personality-related variables. For example, attitudes and perceptions toward the public transit system and consciousness of physical activities derived by using public transit were important factors. Personal health constraints negatively influenced intention to use, while experience with the public transport system was among the positive indicators. The findings show the potential of future interventions in this community to promote use of the new system, such as educational campaigns that improve perceptions of public transit use and clarify the benefits of being active. While providing growing evidence that cognitive variables are important in measuring intention to use public transit, the results emphasize the positive role of efforts integrating transportation and health to develop effective and sustainable solutions.

Beyond the bus stop: where transit users walk

OBJECTIVES

Extending the health benefits of public transit requires understanding how transit use affects pedestrian activity, including pedestrian activity not directly temporally or spatially related to transit use. In this study, we identified where transit users walked on transit days compared with non-transit days within and beyond 400m and 800m buffers surrounding their home and work addresses.

METHODS

We used data collected from 2008-2013 in King County, Washington, from 221 non-physically-disabled adult transit users, who were equipped with an accelerometer, global positioning system (GPS), and travel diary. We assigned walking activity to the following buffer locations: less than and at least 400m or 800m from home, work, or home/work (the home and work buffers comprised the latter buffer). We used Poisson generalized estimating equations to estimate differences in minutes per day of total walking and minutes per day of non-transit-related walking on transit days compared with non-transit days in each location.

RESULTS

We found that durations of total walking and non-transit-related walking were greater on transit days than on non-transit days in all locations studied. When considering the home neighborhood in isolation, most of the greater duration of walking occurred beyond the home neighborhood at both 400m and 800m; results were similar when considering the work neighborhood in isolation. When considering the neighborhoods jointly (i.e., by using the home/work buffer), at 400m, most of the greater duration of walking occurred beyond the home/work neighborhood. However, at 800m, most of the greater duration of walking occurred within the home/work neighborhood.

CONCLUSIONS

Transit days were associated with greater durations of total walking and non-transit related walking within and beyond the home and work neighborhoods. Accordingly, research, design, and policy strategies focused on transit use and pedestrian activity should consider locations outside the home and work neighborhoods, in addition to locations within them.

Correlates of Walking for Travel in Seven European Cities: The PASTA Project

BACKGROUND

Although walking for travel can help in reaching the daily recommended levels of physical activity, we know relatively little about the correlates of walking for travel in the European context.

OBJECTIVE

Within the framework of the European Physical Activity through Sustainable Transport Approaches (PASTA) project, we aimed to explore the correlates of walking for travel in European cities.

METHODS

The same protocol was applied in seven European cities. Using a web-based questionnaire, we collected information on total minutes of walking per week, individual characteristics, mobility behavior, and attitude (N=7,875). Characteristics of the built environment (the home and the work/study addresses) were determined with geographic information system (GIS)-based techniques. We conducted negative binomial regression analyses, including city as a random effect. Factor and principal component analyses were also conducted to define profiles of the different variables of interest.

RESULTS

Living in high-density residential areas with richness of facilities and density of public transport stations was associated with increased walking for travel, whereas the same characteristics at the work/study area were less strongly associated with the outcome when the residential and work/study environments were entered in the model jointly. A walk-friendly social environment was associated with walking for travel. All three factors describing different opinions about walking (ranging from good to bad) were associated with increased minutes of walking per week, although the importance given to certain criteria to choose a mode of transport provided different results according to the criteria.

DISCUSSION

The present study supports findings from previous research regarding the role of the built environment in the promotion of walking for travel and provides new findings to help in achieving sustainable, healthy, livable, and walkable cities. https://doi.org/10.1289/EHP4603.

Mobile Sensing in Environmental Health and Neighborhood Research

Public health research has witnessed a rapid development in the use of location, environmental, behavioral, and biophysical sensors that provide high-resolution objective time-stamped data. This burgeoning field is stimulated by the development of novel multisensor devices that collect data for an increasing number of channels and algorithms that predict relevant dimensions from one or several data channels. Global positioning system (GPS) tracking, which enables geographic momentary assessment, permits researchers to assess multiplace personal exposure areas and the algorithm-based identification of trips and places visited, eventually validated and complemented using a GPS-based mobility survey. These methods open a new space-time perspective that considers the full dynamic of residential and nonresidential momentary exposures; spatially and temporally disaggregates the behavioral and health outcomes, thus replacing them in their immediate environmental context; investigates complex time sequences; explores the interplay among individual, environmental, and situational predictors; performs life-segment analyses considering infraindividual statistical units using case-crossover models; and derives recommendations for just-in-time interventions.

Physical Activity Levels and New Public Transit: A Systematic Review and Meta-analysis

CONTEXT

Physical inactivity is a public health concern as it contributes to the rising burden of noncommunicable diseases. Introducing new public transportation options, such as extending or building new light rail or bus rapid transit stations, could encourage commuters to walk to and from public transit stops, thus increasing their physical activity levels. Despite previous research generally finding positive associations between public transit usage and physical activity levels, few have summarized the association between introducing new public transportation options and different intensities of physical activity. This study aimed to systematically review the current evidence and perform a meta-analysis on this association.

EVIDENCE ACQUISITION

Ten databases were systematically searched for studies published between 1997 and 2017. To ensure comparability, study outcomes were converted to MET hours/week. A random effects meta-analysis and sensitivity analysis were then conducted.

EVIDENCE SYNTHESIS

Nine studies were identified to be included in the systematic review, of which five were eligible for meta-analysis. Pooled results suggest that building new public transit options is associated with a statistically significant increase in light to moderate physical activity levels by 1.76 MET hours/week (95% CI=0.19, 3.32, p=0.03). This is equivalent to increasing walking and other light to moderate physical activity by about 30 minutes per week, relative to baseline. No significant effect was found for the moderate to vigorous physical activity outcome.

CONCLUSIONS

Results show new public transit options can substantially contribute to increasing low- to moderate-intensity exercise levels, which has the potential to improve health on a population scale.

Foot-based audit of streets adjacent to new light rail stations in Houston, Texas: measurement of health-related characteristics of the built environment for physical activity research

Background

Active travel to and from a transit station may provide significant amounts of physical activity and improve health. The ease with which people can traverse the distance to the transit station may impede or support active travel. Therefore, transit stations that have features that are supportive of utilitarian physical activity would be desirable. This study aimed to characterize the built environment surrounding new light rail transit (LRT) stations in the City of Houston, Texas.

Methods

In 2014, we used a series of systematic protocols and a standardized environmental audit instrument, the Analytic Audit Tool, to collect data on segments (streets) that surround 22 LRT stations that were being newly built. Using Geographic Information System (GIS), we assembled all the segments that intersect a 0.25-mile circular buffer around each station for the audit exercise. Several 3- to 4-member teams of trained auditors completed the audit exercise on a subset of these identified segments. Our analysis were descriptive in nature. We provided the frequency distributions of audited features across the study area. We also followed an original algorithm to produce several composite index scores for our study area. The composite index score is indicative of the prevalence of physical activity friendly/unfriendly features in the study area.

Results

In all, we audited a total of 590 segments covering a total of 218 US Census blocks, and eight City of Houston super neighborhoods. Findings suggest the environment around the new LRT stations may not be supportive of physical activity. In general, the audited segments lacked land use integration; had abandoned buildings, had uneven sidewalks; were not bike-friendly, had minimal presence of public-recreational facilities that would support physical activity; and had significant physical disorder. Notably, certain attractive and comfort features were frequently to usually available.

Conclusions

Current findings, which will be compared to follow-up audit data, can be useful for future researchers and practitioners interested in the built environment around LRT stations.

Electronic supplementary material

The online version of this article (10.1186/s12889-019-6560-4) contains supplementary material, which is available to authorized users.

Restructuring the built environment to change adult health behaviors: a scoping review integrated with behavior change frameworks

Built environment restructuring can improve public health through increased opportunity for healthy behaviors. Behavioral science targets individual health behaviors within place, suggesting the potential to integrate these approaches. This scoping review was one of the first to summarise the impact built environment restructuring has on health outcomes and behaviors and integrate these findings with the Capability-Opportunity-Motivation-Behavior model and Theoretical Domains Framework of behavior change. Potential studies were identified from 12 academic databases in urban design, psychology and public health. Search parameters involved 50 environment types, for example green space or healthy cities, combined with both an intervention (e.g. green infrastructure, active transport) and a measurable health outcome (e.g. exercise, wellbeing). Searches were limited to North America, Europe, or Australia/New Zealand. Of 536 potential studies reviewed against defined inclusion/exclusion criteria, 23 contributed to the findings. Evidence supported the positive influence of restructuring on varied health outcomes, many of which were drivers and domains of health behavior. Most studies indicated a clear contribution to increased physical activity. Recommendations include the need for explicit communication of theories guiding restructuring project design, consideration of health outcomes beyond physical activity, and better investigation of unanticipated barriers to health behaviors arising from built environment restructuring projects.

Residents' expectations for new rail stops: Optimistic neighborhood perceptions relate to subsequent transit ridership

Although complete street policies are proliferating, little is known about how nearby residents perceive and act on their new active transportation opportunities. We survey the same neighborhood residents before and after they receive a new complete street renovation with five new light rail stops. We compare Time-1 expectations to use rail with Time-2 evidence of rail use, based on both self-reported and objective GPS/accelerometer measures of ridership. We examine neighborhood perceptions of four groups, created by combining Time-1 expectations to ride with Time-2 ridership: No expect/no ride, no expect/ride, expect/no ride, and expect/ride. The strongest differences were between the no expect/no ride and expect/ride groups. The riders had more positive expectations for light rail's impact on the neighborhood than non-riders; these broad expectations were more powerfully associated with rail ridership than individual barriers to use, such as time constraints or weather. More positive perceptions of the route to rail stops (pleasantness, traffic safety, and crime safety) were also held by riders. Some of the more positive perceptions helped distinguish between the expect/ride group and the expect/no ride group. These results underscore that increasing positive neighborhood perceptions might help convert expected riders into actual riders.

Towards an Integrated Science of Movement: Converging Research on Animal Movement Ecology and Human Mobility Science

There is long-standing scientific interest in understanding purposeful movement by animals and humans. Traditionally, collecting data on individual moving entities was difficult and time-consuming, limiting scientific progress. The growth of location-aware and other geospatial technologies for capturing, managing and analyzing moving objects data are shattering these limitations, leading to revolutions in animal movement ecology and human mobility science. Despite parallel transitions towards massive individual-level data collected automatically via sensors, there is little scientific cross-fertilization across the animal and human divide. There are potential synergies from converging these separate domains towards an integrated science of movement. This paper discusses the data-driven revolutions in the animal movement ecology and human mobility science, their contrasting worldviews and, as examples of complementarity, transdisciplinary questions that span both fields. We also identify research challenges that should be met to develop an integrated science of movement trajectories.

Bringing health into transportation and land use scenario planning: Creating a National Public Health Assessment Model (N-PHAM)

There is mounting evidence linking land development and transportation investments to physical activity with resulting implications for chronic disease prevention. Links between the physical environment and health have traditionally focused on harmful exposures such as air pollution, noise, and traffic injury. Given limited funds and competition for how and where investments are made, there is a need to prioritize and target resources to maximize health benefits that can include activity related chronic disease prevention. The ability to apply this evidence to decision making has been limited by the complexity and inconsistency of research methods, and lack of a direct connection with the planning contexts in which decisions are made. Scenario planning tools provide a method to apply evidence with spatial planning decisions at a range of geographic scales. The US Environmental Protection Agency commissioned the development of a National Public Health Assessment Model (N-PHAM). This project utilized built and natural environment data at the block-group level and large population surveys to model the relationships of the environment with several health outcomes for a range of age and income groups. N-PHAM is the first health assessment tool that can connect to multiple existing scenario planning platforms utilizing nationally available data and can be consistently applied nationally. Such tools can empower communities to choose investments that have the greatest potential to improve public health and quality of life, reduce health care costs, and address environmental justice related disparities.

Methods for Evaluating Natural Experiments in Obesity: A Systematic Review

BACKGROUND

Given the obesity pandemic, rigorous methodological approaches, including natural experiments, are needed.

PURPOSE

To identify studies that report effects of programs, policies, or built environment changes on obesity prevention and control and to describe their methods.

DATA SOURCES

PubMed, CINAHL, PsycINFO, and EconLit (January 2000 to August 2017).

STUDY SELECTION

Natural experiments and experimental studies evaluating a program, policy, or built environment change in U.S. or non-U.S. populations by using measures of obesity or obesity-related health behaviors.

DATA EXTRACTION

2 reviewers serially extracted data on study design, population characteristics, data sources and linkages, measures, and analytic methods and independently evaluated risk of bias.

DATA SYNTHESIS

294 studies (188 U.S., 106 non-U.S.) were identified, including 156 natural experiments (53%), 118 experimental studies (40%), and 20 (7%) with unclear study design. Studies used 106 (71 U.S., 35 non-U.S.) data systems; 37% of the U.S. data systems were linked to another data source. For outcomes, 112 studies reported childhood weight and 32 adult weight; 152 had physical activity and 148 had dietary measures. For analysis, natural experiments most commonly used cross-sectional comparisons of exposed and unexposed groups (n = 55 [35%]). Most natural experiments had a high risk of bias, and 63% had weak handling of withdrawals and dropouts.

LIMITATION

Outcomes restricted to obesity measures and health behaviors; inconsistent or unclear descriptions of natural experiment designs; and imperfect methods for assessing risk of bias in natural experiments.

CONCLUSION

Many methodologically diverse natural experiments and experimental studies were identified that reported effects of U.S. and non-U.S. programs, policies, or built environment changes on obesity prevention and control. The findings reinforce the need for methodological and analytic advances that would strengthen evaluations of obesity prevention and control initiatives.

PRIMARY FUNDING SOURCE

National Institutes of Health, Office of Disease Prevention, and Agency for Healthcare Research and Quality. (PROSPERO: CRD42017055750).

Associations of mode of travel to work with physical activity, and individual, interpersonal, organisational, and environmental characteristics

INTRODUCTION

Encouraging walking during the daily commute is a potential strategy for increasing physical activity levels. This study aimed: (i) to examine, and compare by travel mode, the objectively measured physical activity of a working adult population, and, (ii) to identify associations between mode of travel to work and a range of individual, interpersonal, organisational and environmental characteristics.

METHODS

Employees (n=654) recruited from 87 workplaces in geographically distinct areas provided data through accelerometers, Global Positioning System (GPS) receivers, travel diaries and questionnaires. Separate multivariable logistic regression models were developed to examine factors associated with physical activity during the commute and mode of travel to work.

RESULTS

In comparison to car users (7.3 minutes±Standard Deviation 7.6), walkers (34.3±18.6) and public transport users (25.7±14.0) accrued substantially higher levels of daily moderate to vigorous physical activity during the commute. Combined accelerometer and GPS data showed that participants who walked at least ten minutes during their commute were more likely to have a shorter commute distance (p<0.001), occupy a sedentary job (p<0.01), and be classified as 'underweight or normal weight' (p<0.03). No car access (p<0.001), and absence of free work car parking (p<0.01) were independently related to walking to work and using public transport. Shorter commuting distances were also related to walking to work (p<0.001). Public transport users were more likely to be younger (p=0.04), have more positive environmental perceptions (p=0.01), and less likely to combine their commute with caring responsibilities (p=0.03).

CONCLUSIONS

This study shows that walking to work and using public transport are important contributors to physical activity levels in a working population. Planning, transport and behavioural interventions to promote walking during the commute should take into account the wider determinants. Reducing availability of free work car parking is one possible strategy to discourage car use.

Impact of new rapid transit on physical activity: A meta-analysis

New rapid transit investments have been motivated by environmental, economic, and health benefits. Given transit's potential to increase active travel, recent research leverages transit changes for natural experiment studies to examine physical activity outcomes. We aimed to quantify the association size, critically examine existing literature, and make recommendations for future studies to advance research and policies on active travel, transportation, and physical activity. Studies of physical activity impacts following transit interventions were systematically reviewed using seven health and transport databases (May-July 2017). Two investigators extracted data on sample size, intervention, pre- and post-intervention physical activity, and relevant measurement information. Inconsistency of results and estimated overall mean physical activity change post-intervention were assessed. Forest plots were created from physical activity change in each study using a general variance-based random effects model. Of 18 peer-reviewed articles examining health behaviors, 15 addressed physical activity and five were natural experiment studies with pre- and post- intervention measurements. Studies varied by intervention, duration, outcome measurement, sampling location, and spatial method. Q (201) and I2 (98%) indicated high study heterogeneity. Among these five studies, after transit interventions, total physical activity decreased (combined mean - 80.4 min/week, 95% CI - 157.9, -2.9), but transport-related physical activity increased (mean 6.7 min/week, 95% CI - 10.1, 23.5). Following new transit infrastructure, total physical activity may decline but transport-related physical activity may increase. Positive transit benefits were location, sociodemographic, or activity-specific. Future studies should address context, ensure adequate follow-up, utilize controls, and consider non-residential environments or participants.

Examining the Influence of a New Light Rail Line on the Health of a Demographically Diverse and Understudied Population within the Washington, D.C. Metropolitan Area: A Protocol for a Natural Experiment Study

Approximately two-thirds of adults and youth in Prince George's County, Maryland, a suburb of Washington, D.C. are overweight or obese and less than half are achieving daily physical activity recommendations. Active transportation (AT), such as walking, biking or using public transportation (PT), is a strategic pathway to improving physical activity levels and thus reducing excess weight. Utilizing an expansion of the Washington, D.C. area transportation system with a new light rail line, the Purple Line Outcomes on Transportation (PLOT) Study will exam pre- and post-Purple Line PT use, AT behaviors and attitudes and physical activity among Prince George's County adults and youth. The PLOT Study will take advantage of this natural experiment in an area enduring significant racial/ethnic and gender-based overweight or obesity and physical inactivity disparities. While similar natural experiments on AT have been conducted in other U.S. cities, those studies lacked diverse and representative samples. To effectively evaluate these physical activity outcomes among this population, efforts will be used to recruit African American and Latino populations, the first and second most common racial/ethnic groups in Prince George's County. Finally, the PLOT Study will also examine how contextual effects (e.g., neighborhood built environment) impact PT, AT and physical activity.

Do Natural Experiments of Changes in Neighborhood Built Environment Impact Physical Activity and Diet? A Systematic Review

Physical activity and diet are major modifiable risk factors for chronic disease and have been shown to be associated with neighborhood built environment. Systematic review evidence from longitudinal studies on the impact of changing the built environment on physical activity and diet is currently lacking. A systematic review of natural experiments of neighborhood built environment was conducted. The aims of this systematic review were to summarize study characteristics, study quality, and impact of changes in neighborhood built environment on physical activity and diet outcomes among residents. Natural experiments of neighborhood built environment change, exploring longitudinal impacts on physical activity and/or diet in residents, were included. From five electronic databases, 2084 references were identified. A narrative synthesis was conducted, considering results in relation to study quality. Nineteen papers, reporting on 15 different exposures met inclusion criteria. Four studies included a comparison group and 11 were pre-post/longitudinal studies without a comparison group. Studies reported on the impact of redeveloping or introducing cycle and/or walking trails (n = 5), rail stops/lines (n = 4), supermarkets and farmers' markets (n = 4) and park and green space (n = 2). Eight/15 studies reported at least one beneficial change in physical activity, diet or another associated health outcome. Due to limitations in study design and reporting, as well as the wide array of outcome measures reported, drawing conclusions to inform policy was challenging. Future research should consider a consistent approach to measure the same outcomes (e.g., using measurement methods that collect comparable physical activity and diet outcome data), to allow for pooled analyses. Additionally, including comparison groups wherever possible and ensuring high quality reporting is essential.

Transit use and physical activity: Findings from the Houston travel-related activity in neighborhoods (TRAIN) study

Transportation-related physical activity can significantly increase daily total physical activity through active transportation or walking/biking to transit stops. The purpose of this study was to assess the relations between transit-use and self-reported and monitor-based physical activity levels in a predominantly minority population from the Houston Travel-Related Activity in Neighborhoods (TRAIN) Study. This was a cross-sectional analysis of 865 adults living in Houston, Texas between 2013 and 2015. The exposure variable was transit-use (non-users, occasional users, and primary users). Self-reported and accelerometer-determined physical activity were the outcomes of interest. Regression models adjusting for age, sex, race/ethnicity, and other covariates of interest were built to test the hypothesis that transit user status was directly associated with 1) minutes of moderate-intensity physical activity and 2) the prevalence of achieving the physical activity guidelines. The majority of participants were female, non-Hispanic black, and almost one-third had a high school education or less. After adjustment, primary transit-use was associated with 134.2 (p < 0.01) additional mean minutes per week of self-reported moderate-intensity transportation-related physical activity compared to non-users. Further, primary users had 7.3 (95% CI: 2.6-20.1) times the relative adjusted odds of meeting physical activity recommendations than non-users based on self-reported transportation-related physical activity. There were no statistically significant associations of transit-use with self-reported leisure-time or accelerometer-derived physical activity. Transit-use has the potential for a large public health impact due to its sustainability and scalability. Therefore, encouraging the use of transit as a means to promote physical activity should be examined in future studies.

Simulating the Impact of Crime on African American Women's Physical Activity and Obesity

OBJECTIVE

The objective of this study was to quantify the impact of crime on physical activity location accessibility, leisure-time physical activity (LTPA), and obesity among African American women.

METHODS

An agent-based model was developed in 2016 to represent resource-limited Washington, DC, communities and their populations to simulate the impact of crime on LTPA and obesity among African American women under different circumstances.

RESULTS

Data analysis conducted between 2016 and 2017 found that in the baseline scenario, African American women had a 25% probability of exercising. Reducing crime so more physical activity locations were accessible (increasing from 10% to 50%) decreased the annual rise in obesity prevalence by 2.69%. Increasing the probability of African American women to exercise to 37.5% further increased the impact of reducing crime on obesity (2.91% annual decrease in obesity prevalence).

CONCLUSIONS

These simulations showed that crime may serve as a barrier to LTPA. Reducing crime and increasing propensity to exercise through multilevel interventions (i.e., economic development initiatives to increase time available for physical activity and subsidized health care) may promote greater than linear declines in obesity prevalence. Crime prevention strategies alone can help prevent obesity, but combining such efforts with other ways to encourage physical activity can yield even greater benefits.

Analyzing Walking Route Choice through Built Environments using Random Forests and Discrete Choice Techniques

Walking is a form of active transportation with numerous benefits, including better health outcomes, lower environmental impacts and stronger communities. Understanding built environmental associations with walking behavior is a key step towards identifying design features that support walking. Human mobility data available through GPS receivers and cell phones, combined with high resolution walkability data, provide a rich source of georeferenced data for analyzing environmental associations with walking behavior. However, traditional techniques such as route choice models have difficulty with highly dimensioned data. This paper develops a novel combination of a data-driven technique with route choice modeling for leveraging walkability audits. Using data from a study in Salt Lake City, Utah, USA, we apply the data-driven technique of random forests to select variables for use in walking route choice models. We estimate data-driven route choice models and theory-driven models based on predefined walkability dimensions. Results indicate that the random forest technique selects variables that dramatically improve goodness of fit of walking route choice models relative to models based on predefined walkability dimensions. We compare the theory-driven and data-driven walking route choice models based on interpretability and policy relevance.

Increased Walking's Additive and No Substitution Effect on Total Physical Activity

PURPOSE

We assessed the associations between a change in time spent walking and a change in total physical activity (PA) time within an urban living adult sample to test for additive or substitution effects.

METHODS

Participants living in the greater Seattle area were assessed in 2008-2009 and again 1-2 yr later (2010-2011). At each time point, they wore accelerometers and GPS units and recorded trips and locations in a travel diary for seven consecutive days. These data streams were combined to derive a more objective estimate of walking and total PA. Participants also completed the International Physical Activity Questionnaire to provide self-reported estimates of walking and total PA. Regression analyses assessed the associations between within-participant changes in objective and self-reported walking and total PA.

RESULTS

Data came from 437 participants. On average, a 1-min increase in total walking was associated with an increase in total PA of 1 min, measured by objective data, and 1.2-min, measured by self-reported data. A similar additive effect was consistently found with utilitarian, transportation, or job-related walking, measured by both objective and self-reported data. For recreational walking, the effect of change was mixed between objective and self-reported results.

CONCLUSION

Both objective and self-reported data confirmed an additive effect of utilitarian and total walking on PA.

Complex active travel bout motivations: Gender, place, and social context associations

Active travel bouts are healthy, but bout-specific motives, social, and physical contexts have been poorly characterized. Adults (n= 421 in 2012, 436 in 2013) described their moderate activity bouts over the past week, aided by accelerometry/GPS data integration. Participants viewed maps indicating date, time, and starting and ending locations of their past week moderate-to-vigorous active travel bouts of 3 or more minutes. These prompts helped participants recall their social and physical contexts and motives for the bouts. Three bout motivations were modeled: leisure, transportation, and their "T-L" difference scores (transportation minus leisure scores). Blends of leisure and transportation motives characterized most bouts, even though most studies do not allow participants to endorse multiple motives for their active travel. Bouts were often neighborhood-based. Leisure motives were related to pleasant place perceptions, homes, and exercise places; workplaces were associated with stronger transportation and T-L bout motives. Women's bout motives were more closely associated with place than men's. Our novel method of individual bout assessment can illuminate the social-ecological contexts and experiences of everyday healthy bouts of activity.

Objectively measured active travel and uses of activity-friendly neighborhood resources: Does change in use relate to change in physical activity and BMI?

Few studies examine how objectively measured use of local physical activity resources contributes to objectively-measured healthy physical activity and weight changes over time. We utilized objective measures to test whether changes in active travel and uses of three physical activity (PA) resources–parks, recreation centers, and transit– related to changes in PA and BMI. Adults (n = 536) in Salt Lake City, UT, wore accelerometer and GPS units in 2012 and 2013, before and after neighborhood rail completion. Regression outcomes included accelerometer counts per minute (cpm), MVPA (moderate-to-vigorous activity minutes/10 h accelerometer wear) and measured BMI; key predictors were changes in active travel and PA resource uses (former and new uses). Significant results (all p < 0.05) showed that increased active travel related to increased total PA (59.86 cpm and 8.50 MVPA); decreased active travel related to decreased MVPA (− 3.01 MVPA). Poorer outcomes were seen after discontinuing use of parks (− 36.29 cpm, − 5.73 MVPA, and + 0.44 BMI points), recreation centers (− 6.18 MVPA), and transit (− 48.14 cpm, − 5.43 MVPA, and + 0.66 BMI). Healthier outcomes were seen after commencing use of parks (29.83 cpm, 5.25 MVPA), recreation centers (44.63 cpm) and transit (38.44 cpm, 4.17 MVPA, and − 0.56 BMI). Transit and park/recreational center uses were unrelated, although park users were more likely to be recreation center users. Active travel and use of three neighborhood PA resources relate to healthy activity and could be fostered by policy and design.

•

GPS & accelerometer measures show active travel changes relate to PA changes.

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Increasing park, recreation center, or transit uses relates to more PA.

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Decreasing park, recreation center, or transit uses relates to less PA.

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Changing transit use does not change park or recreation use, and vice versa.

•

Policy should enhance active transportation and tie it to recreation options.

Analyzing the impact of public transit usage on obesity

The objective of this paper is to estimate the impact of county-level public transit usage on obesity prevalence in the United States and assess the potential for public transit usage as an intervention for obesity. This study adopts an instrumental regression approach to implicitly control for potential selection bias due to possible differences in commuting preferences among obese and non-obese populations. United States health data from the 2009 Behavioral Risk Factor Surveillance System and transportation data from the 2009 National Household Travel Survey are aggregated and matched at the county level. County-level public transit accessibility and vehicle ownership rates are chosen as instrumental variables to implicitly control for unobservable commuting preferences. The results of this instrumental regression analysis suggest that a one percent increase in county population usage of public transit is associated with a 0.221 percent decrease in county population obesity prevalence at the α=0.01 statistical significance level, when commuting preferences, amount of non-travel physical activity, education level, health resource, and distribution of income are fixed. Hence, this study provides empirical support for the effectiveness of encouraging public transit usage as an intervention strategy for obesity.

Geographic regions for assessing built environmental correlates with walking trips: A comparison using different metrics and model designs

There is growing international evidence that supportive built environments encourage active travel such as walking. An unsettled question is the role of geographic regions for analyzing the relationship between the built environment and active travel. This paper examines the geographic region question by assessing walking trip models that use two different regions: walking activity spaces and self-defined neighborhoods. We also use two types of built environment metrics, perceived and audit data, and two types of study design, cross-sectional and longitudinal, to assess these regions. We find that the built environment associations with walking are dependent on the type of metric and the type of model. Audit measures summarized within walking activity spaces better explain walking trips compared to audit measures within self-defined neighborhoods. Perceived measures summarized within self-defined neighborhoods have mixed results. Finally, results differ based on study design. This suggests that results may not be comparable among different regions, metrics and designs; researchers need to consider carefully these choices when assessing active travel correlates.

Harnessing Technology and Citizen Science to Support Neighborhoods that Promote Active Living in Mexico

Middle- and low-income countries bear 80 % of the global chronic disease burden. Population-level, multi-sectoral approaches to promoting healthful lifestyles that take into local physical, socioeconomic, and sociocultural characteristics of both the environment and the population are needed. The "Nuestra Voz (Our Voice)" is one such approach that involves neighborhood residents acting as "citizen scientists" to systematically gather information on the barriers and facilitators of physical activity in their neighborhoods and then use their data to collectively advocate for local environmental- and policy-level changes to support active living. We pilot tested this approach in Cuernavaca, Mexico with adults and adolescents. This community-engaged and participatory approach is driven by residents, who utilize a GPS-enabled electronic tablet-based application with simple audio-based instructions to take photographs and record audio narratives of facets of their neighborhood that promote or hinder active living. After collecting these data, the citizen scientists come together in a community meeting and use their data to prioritize realistic, multi-level changes for promoting active living in their neighborhoods. A survey assessed participants' acceptability of the approach. Participating citizen scientists included 32 adults and 9 adolescents. The citizen scientists rated the acceptability of five of the nine acceptability survey items with an average of 4.0 or higher out of 5.0, indicating they thought it was "fun," were comfortable carrying the tablet, were likely to use it again, and would recommend it to friends and family. Items with average scores of less than 4 were all related to safety concerns. The most common barriers reported by citizen scientists using the tablet were poor sidewalk quality, presence of trash, negative characteristics of the streets, unpleasant aesthetics (e.g., graffiti), and presence of parks and recreational facilities. The Our Voice citizen scientist approach using the Discovery Tool has high potential for assisting communities in diverse settings to begin to identify both local barriers to active living as well as potentially useful strategies for promoting physical activity in culturally congruent ways that are appropriate and feasible in the local context.

Changes in bicycling over time associated with a new bike lane: relations with kilocalories energy expenditure and body mass index

Although bicycling has been related to positive health indicators, few studies examine health-related measures associated with non-competitive community cycling before and after cycling infrastructure improvements. This study examined cycling changes in a neighborhood receiving a bike lane, light rail, and other "complete street" improvements. Participants wore accelerometers and global positioning system (GPS) data loggers for one week in both 2012 and 2013, pre- and post- construction completion. Participants sampled within 2 km of the complete street improvements had the following patterns of cycling: never cyclists (n=434), continuing cyclists (n= 29), former cyclists (n=33, who bicycled in 2012 but not 2013), and new cyclists (n=40, who bicycled in 2013 but not 2012). Results show that all three cycling groups, as identified by GPS/accelerometry data, expended more estimated kilocalories (kcal) of energy per minute during the monitoring week than those who were never detected cycling, net of control variables. Similar but attenuated results emerged when cycling self-report measures were used. BMI was not related to cycling group but those who cycled longer on the new path had lower BMI. Although cyclists burn more calories than non-cyclists across the week, among cyclists, their cycling days involved more calories expended than their non-cycling days. The new cyclists account for 39% of the cyclists identified in this study and former cyclists account for 32% of cyclists. These results suggest that cycling is healthy, but that sustaining rates of cycling will be an important goal for future policy and research.

A Complete Street Intervention for Walking to Transit, Nontransit Walking, and Bicycling: A Quasi-Experimental Demonstration of Increased Use

BACKGROUND

Complete streets require evaluation to determine if they encourage active transportation.

METHODS

Data were collected before and after a street intervention provided new light rail, bike lanes, and better sidewalks in Salt Lake City, Utah. Residents living near (<800 m) and far (≥801 to 2000 m) from the street were compared, with sensitivity tests for alternative definitions of near (<600 and <1000 m). Dependent variables were accelerometer/global positioning system (GPS) measures of transit trips, nontransit walking trips, and biking trips that included the complete street corridor.

RESULTS

Active travel trips for Near-Time 2 residents, the group hypothesized to be the most active, were compared with the other 3 groups (Near-Time 1, Far-Time 1, and Far-Time 2), net of control variables. Near-Time 2 residents were more likely to engage in complete street transit walking trips (35%, adjusted) and nontransit walking trips (50%) than the other 3 groups (24% to 25% and 13% to 36%, respectively). Bicycling was less prevalent, with only 1 of 3 contrasts significant (10% of Near-Time 2 residents had complete street bicycle trips compared with 5% of Far-Time 1 residents).

CONCLUSIONS

Living near the complete street intervention supported more pedestrian use and possibly bicycling, suggesting complete streets are also public health interventions.

Potential Health Implications and Health Cost Reductions of Transit-Induced Physical Activity

Transit has the potential to increase an individual's level of physical activity due to the need to walk or bike at the beginning and end of each trip. Consideration of these health benefits would allow transit proponents to better demonstrate its true costs and benefits. In light of transit's potential health-related impacts, this study contributes to the growing discussion in the emerging field of health and transportation by providing a review of the current level of understanding and evidence related to the physical activity implications of transit use and its associated health cost benefits. Findings from the review revealed that transit use is associated with increased levels of physical activity and improved health outcomes, but the magnitude of these effects is uncertain. There were few studies that estimated the health care cost savings of transit systems, and those that did tended to be imprecise and simplistic. Objective physical activity measures and frequency-based transit measures would allow for greater consistency across studies and help more directly attribute physical activity gains to transit ridership. Additionally, research in this area would benefit from disaggregate estimation techniques and more robust health datasets that can be better linked with existing transit data.