Identifying multilevel predictors of behavioral outcomes like park use: A comparison of conditional and marginal modeling approaches.

This study compared marginal and conditional modeling approaches for identifying individual, park and neighborhood park use predictors. Data were derived from the ParkIndex study, which occurred in 128 block groups in Brooklyn (New York), Seattle (Washington), Raleigh (North Carolina), and Greenville (South Carolina). Survey respondents (n = 320) indicated parks within one half-mile of their block group used within the past month. Parks (n = 263) were audited using the Community Park Audit Tool. Measures were collected at the individual (park visitation, physical activity, sociodemographic characteristics), park (distance, quality, size), and block group (park count, population density, age structure, racial composition, walkability) levels. Generalized linear mixed models and generalized estimating equations were used. Ten-fold cross validation compared predictive performance of models. Conditional and marginal models identified common park use predictors: participant race, participant education, distance to parks, park quality, and population >65yrs. Additionally, the conditional mode identified park size as a park use predictor. The conditional model exhibited superior predictive value compared to the marginal model, and they exhibited similar generalizability. Future research should consider conditional and marginal approaches for analyzing health behavior data and employ cross-validation techniques to identify instances where marginal models display superior or comparable performance.

Physical Activity Promotion in North Carolina: a Reassessment of Public Park and Recreation Directors.

Regular physical activity is widely considered by public health and parks and recreation professionals as a key determinant of individual and community health and well-being. Prior research has shown that building sustainable health partnerships with community organizations can help parks and recreation departments meet many US health challenges. This descriptive study examined the perceptions of North Carolina public parks and recreation directors regarding physical activity and health partnership practices in their communities. The study was also a 15-year follow-up to a study and examined whether park and recreation director perceptions of health partnerships had changed given the many social, economic, and health events that have occurred since the original survey. Directors from two hundred seventy-five North Carolina city and county parks and recreation departments were surveyed in the Spring of 2022 to determine 1) directors' effort allocation in promoting physical activity toward vulnerable populations, 2) challenges associated with promoting community physical activity, and 3) differences in effort allocation, future priorities, and partnership among varying director and departmental demographics. Results were compared to findings from a 2007 study of NC perceptions of health partnerships, upon which the present study was based. One hundred twenty-three completed questionnaires were returned, resulting in a response rate of 45%. Directors in 2022 allocated similarly higher levels of effort toward older adults, families, and people with low income as did directors in 2007, while youth and adults with disabilities and people with chronic health conditions received lower allocations of effort from directors in 2022. Barriers such as lack of staff knowledge on how to promote physical activity, lack of citizen and political support, and lack of knowledge of under-represented groups' physical activity preferences were less pronounced in 2022 compared to 2007. Several distinct differences were revealed between female and male directors' rankings of effort and future priorities, as well as their perceptions of physical activity opportunities for women and people with disabilities. Partnerships with county health departments are being reported more in counties with the highest health disparities compared to more healthy counties, indicating that partnerships are being targeted and implemented in areas where resources are most needed. This study represents a meaningful extension of research conducted prior to the 2008 Great Recession and COVID-19 pandemic and provides recommendations for public parks and recreation departments to consider promoting physical activity and building community resilience in the face of future economic and health challenges.

Associations Between Neighborhood Opportunity and Indicators of Physical Fitness for New York City Public School Youth.

Background: Fewer than 1/4th of US children and adolescents meet physical activity (PA) guidelines, leading to health disparities that track into adulthood. Neighborhood opportunity may serve as a critical modifiable factor to improve fitness attainment and reduce these disparities. We drew data from the Child Opportunity Index to examine associations between neighborhood indicators of opportunity for PA and multiple fitness indicators among New York City public school youth. Methods: Multilevel generalized linear mixed models were used to estimate the overall and sex-stratified associations between neighborhood indicators (green space, healthy food, walkability, commute time) and indicators for physical fitness [curl-ups, push-ups, Progressive Aerobic Cardiovascular Endurance Run (PACER), sit-and-reach] using the New York City FITNESSGRAM data set. Results: The analytic sample [n = 299,839; median (interquartile range) age = 16 (12-17)] was 50.1% female, 37.5% Hispanic, 26.2% non-Hispanic Black, and most (69.5%) qualified for free/reduced price school meals. Neighborhood indicators were positively associated with higher values of indicators for physical fitness. The strongest associations were observed between walkability and both BMI and PACER, and commute time with BMI, push-ups, and PACER. For example, walkability had the greatest magnitude of effects for BMI and muscular strength and endurance (BMI: ß: -0.75, 95% confidence interval, CI: -1.01 to -0.49; PACER: ß: 1.98, 95% CI: 1.59 to 2.37), and particularly for girls compared with boys (BMI, girls: ß: -0.91, 95% CI: -1.22 to -0.66); BMI, boys: ß: -0.56, 95% CI: -0.86 to -0.25); PACER, girls: ß: 2.11, 95% CI: 1.68 to 2.54; push-ups, boys: ß: 1.71, 95% CI: 1.31 to 2.12). Conclusion: Neighborhood indicators were associated with multiple measures of youth fitness. Continued research on neighborhood opportunity and youth fitness may better inform place-based public health interventions to reduce disparities.

The relationship between greenspace exposure and telomere length in the National Health and Nutrition Examination Survey.

The exposome, reflecting the range of environmental exposures individuals encounter throughout their life, can influence a variety of health outcomes and can play a role in how the environment impacts our genes. Telomeres, genetic structures regulating cell growth and senescence, are one pathway through which the exposome may impact health. Greenspace exposure, representing the amount of green areas in one's neighborhood, is one component of the exposome and has been associated with multiple health benefits. To investigate the potential link between greenspace exposure and telomere length, we analyzed data from the 1999-2001 National Health and Nutrition Examination Survey (NHANES) sample. Our study examined individual, risk, and contextual factors. We found that greater greenspace exposure in one's neighborhood was associated with longer telomere lengths when considering individual and risk factors, suggesting a positive effect of living in greener neighborhoods. However, this relationship became non-significant when contextual factors, such as air pollution and deprivation, were included in the analysis. These findings highlight a complex relationship between greenspace and telomere length, warranting further research to explore contextual factors in detail.

Longitudinal Associations Between Neighborhood Child Opportunity and Physical Fitness for New York City Public School Youth.

Neighborhood environments can support fitness-promoting behavior, yet little is known about their influence on youth physical fitness outcomes over time. We examined longitudinal associations between neighborhood opportunity and youth physical fitness among New York City (NYC) public school youth. The Child Opportunity Index (COI), a composite index of 29 indicators measuring neighborhood opportunity at the census-tract level, along with scores on 4 selected COI indicators were linked to NYC FITNESSGRAM youth data at baseline. Fitness outcomes (measured annually, 2011-2018) included body mass index, curl-ups, push-ups, and Progressive Aerobic Cardiovascular Endurance Run (PACER) laps. Unstratified and age-stratified, adjusted, 3-level generalized linear mixed models, nested by census tract and time, estimated the association between COI and fitness outcomes. The analytical sample (n = 204,939) lived in very low (41%) or low (30%) opportunity neighborhoods. Unstratified models indicated that overall COI is modestly associated with improved youth physical fitness outcomes. The strongest opportunity-fitness associations were observed for PACER. Stratified models show differences in associations across younger vs. older youth. We find that neighborhood factors are associated with youth fitness outcomes over time, with the strength of the associations dependent on age. Future implications include better informed place-based interventions tailored to specific life stages to promote youth health.

Need and Interest in Nature Prescriptions to Protect Cardiovascular and Mental Health: A Nationally-Representative Study With Insights for Future Randomised Trials.

OBJECTIVE: "Nature prescriptions" are increasingly being adopted by health sectors as an adjunct to standard care to attend to health and social needs. We investigated levels of need and interest in nature prescriptions in adults with cardiovascular diseases, psychological distress and concomitants (e.g. physical inactivity, sedentary behaviour, obesity, loneliness, burn-out). METHODS: A nationally-representative survey of 3,319 adults across all states and territories of Australia was completed in February 2021 (response 84.0%). Participants were classified across 15 target groups using validated health indicators and surveyed on (1) time and frequency of visits to green and blue spaces (nature spaces), (2) interest in a nature prescription, and (3) potential confounders (e.g. age, income). Analyses were done using weighted logistic regressions. RESULTS: The sample was 50.5% female, 52.0% were aged ≥45 years, 15.2% were living alone and 19.3% were born overseas in non-English-speaking countries. Two-thirds of the sample spent 2 hours or more a week in nature, but these levels were generally lower in target groups (e.g. 57.7% in adults with type 2 diabetes). Most participants (81.9%) were interested in a nature prescription, even among those spending fewer than 2 hours a week in nature (76.4%). For example, 2 hours a week or more in nature was lowest among sedentary adults (36.9%) yet interest in nature prescriptions in this group was still high (74.0%). Lower levels of nature contact in target groups was not explained by differences in access to or preference for local nature spaces. CONCLUSIONS: High levels of interest in nature prescriptions amid low levels of nature contact in many target health groups provides impetus for developing randomised trials of interventions that enable people to spend more time in nature. These findings can inform intervention co-design processes with a wide range of community stakeholders, end-users in target health groups, and the health professionals who support them.

Prescribing Time in Nature for Human Health and Well-Being: Study Protocol for Tailored Park Prescriptions.

Background: eHealth technologies offer an efficient method to integrate park prescriptions into clinical practice by primary health care (PHC) providers to help patients improve their health via tailored, nature-based health behavior interventions. This paper describes the protocol of the GoalRx Prescription Intervention (GPI) which was designed to leverage community resources to provide tailored park prescriptions for PHC patients. Methods: The GPI study was designed as a 3-arm, multi-site observational study. We enrolled low-income, rural adults either at-risk of or living with hypertension or diabetes (n = 75) from Federally Qualified Health Centers (FQHC) in two counties in North Carolina, USA into the 3-month intervention. Eligible participants self-selected to receive (1) a tailored park prescription intervention; (2) a tailored home/indoor PA prescription intervention; or (3) a healthy eating prescription (with no PA prescription beyond standard PA counseling advice that is already routinely provided in PHC) as the comparison group. The GPI app paired patient health data from the electronic health record with stated patient preferences and triggered app-integrated SMS motivation and compliance messaging directly to the patient. Patients were assessed at baseline and at a 3-month follow-up upon the completion of the intervention. The primary outcome (mean difference in weekly physical activity from baseline (T0) to post-intervention (T1) as measured by the Fitbit Flex 2) was assessed at 3 months. Secondary outcomes included assessment of the relationship between the intervention and biological markers of health, including body mass index (BMI), systolic and diastolic blood pressure, HbA1c or available glucose test (if applicable), and a depression screen score using the Patient Health Questionnaire 9. Secondary outcomes also included the total number of SMS messages sent, number of SMS messages responded to, number of SMS messages ignored, and opt-out rate. Discussion: The goal was to create a protocol utilizing eHealth technologies that addressed the specific needs of rural low-income communities and fit into the natural rhythms and processes of the selected FQHC clinics in North Carolina. This protocol offered a higher standard of health care by connecting patients to their PHC teams and increasing patient motivation to make longer-lasting health behavior changes.

GPS-based activity space exposure to greenness and walkability is associated with increased accelerometer-based physical activity.

INTRODUCTION: Built and natural environments may provide opportunities for physical activity. However, studies are limited by primarily using residential addresses to define exposure and self-report to measure physical activity. We quantified associations between global positioning systems (GPS)-based activity space measures of environmental exposure and accelerometer-based physical activity. METHODS: Using a nationwide sample of working female adults (N = 354), we obtained seven days of GPS and accelerometry data. We created Daily Path Area activity spaces using GPS data and linked these activity spaces to spatial datasets on walkability (EPA Smart Location Database at the Census block group level) and greenness (satellite vegetation at 250 m resolution). We utilized generalized additive models to examine nonlinear associations between activity space exposures and accelerometer-derived physical activity outcomes adjusted for demographic characteristics, socioeconomic factors, and self-rated health. RESULTS: Higher activity space walkability was associated with higher levels of moderate-vigorous physical activity, and higher activity space greenness was associated with greater numbers of steps per week. No strong relationships were observed for sedentary behavior or light physical activity. Highest levels of moderate-vigorous physical activity were observed for participants with both high walkability and high greenness in their activity spaces. CONCLUSION: This study contributes evidence that higher levels of physical activity occur in environments with more dense, diverse, and well-connected built environments, and with higher amounts of vegetation. These data suggest that urban planners, landscape architects, and policy makers should implement and evaluate environmental interventions to encourage higher levels of physical activity.

Nature-based Pathways to Health Promotion: The Value of Parks and Greenspace.

The built environment is a key social determinant of health. Exposure to parks and greenspace can improve physical and mental health and provide other benefits that enhance well-being. Programs and initiatives that capitalize on nature-based opportunities offer health care providers with a cost-effective alternative for upstream health promotion.

Measuring Nature Contact: A Narrative Review.

While many studies suggest evidence for the health benefits of nature, there is currently no standardized method to measure time spent in nature or nature contact, nor agreement on how best to define nature contact in research. The purpose of this review is to summarize how nature contact has been measured in recent health research and provide insight into current metrics of exposure to nature at individual and population scales. The most common methods include surrounding greenness, questionnaires, and global positioning systems (GPS) tracking. Several national-level surveys exist, though these are limited by their cross-sectional design, often measuring only a single component of time spent in nature, and poor links to measures of health. In future research, exposure assessment combining the quantifying (e.g., time spent in nature and frequency of visits to nature) and qualifying (e.g., greenness by the normalized difference of vegetation index (NDVI) and ratings on perception by individuals) aspects of current methods and leveraging innovative methods (e.g., experience sampling methods, ecological momentary assessment) will provide a more comprehensive understanding of the health effects of nature exposure and inform health policy and urban planning.

Frequency of Neighborhood Park Use Is Associated With Physical Activity Among Adults in Four US Cities.

BACKGROUND: Neighborhood parks are recognized as important spaces for facilitating physical activity (PA); however, it remains unclear how the frequency of park use is associated with PA. The purpose of this study was to examine associations between minutes of moderate to vigorous PA and multiple park use indicators: (1) use of a neighborhood park, (2) unique number of neighborhood parks used, and (3) frequency of neighborhood park use. METHODS: Adults were surveyed from 4 US cities (Brooklyn, NY; Greenville County, SC; Raleigh, NC; and Seattle, WA). Using a map-based survey platform, participants indicated all neighborhood parks they used and the frequency of use in the past 30 days. Participants self-reported their weekly moderate to vigorous PA. Quantile regression was used to examine associations between PA and park use indicators. RESULTS: Of all respondents (N = 360), 60% indicated visiting a neighborhood park in the past 30 days, with an average of about 13 total neighborhood park visits (SD = 17.5). Significant, positive associations were found between moderate to vigorous PA and both unique neighborhood park visits and total number of neighborhood parks visits. CONCLUSIONS: Frequency of park visitation is associated with PA among US adults. Ensuring equitable and safe access to neighborhood parks has the potential for population-level PA health benefits.

The association between neighborhood quality, youth physical fitness, and modifiable cardiovascular disease risk factors.

PURPOSE: Striking disparities persist in cardiovascular disease risk factors among minority youth. We examined the association between multiple indicators of neighborhood quality and minority youth fitness. METHODS: The primary exposure was the Child Opportunity Index (COI), a measure comprised of indicators that facilitate healthy child development. Outcome data were drawn from the 2018-2019 Fit2Play Study (Miami-Dade County, FL). Hotspot analysis evaluated COI spatial clustering. Generalized linear mixed models examined cross-sectional COI-fitness associations. RESULTS: The sample included 725 youth (53% Black, 43% Hispanic; 5-17 years). Significant neighborhood quality spatial clusters were identified (Gi*z-score = -4.85 to 5.36). Adjusting for sociodemographics, walkability was associated with lower percentiles in body mass index (BMI) and diastolic blood pressure percentiles (DBP) (ß = -5.25, 95% CI: -8.88, -1.62 and ß = -3.95, 95% CI: -7.02, -0.89, respectively) for all, lower skinfold thickness (ß = -4.83, 95% CI: -9.97, 0.31 and higher sit-ups (ß = 1.67, 95% CI: -0.17, 3.50) among girls, and lower systolic blood pressure percentiles (SBP) (ß = -4.75, 95% CI: -8.99, -0.52) among boys. Greenspace was associated with higher BMI (ß = 6.17, 95% CI: 2.47, 9.87), SBP (ß = 3.47, 95% CI: -0.05, 6.99), and DBP (ß = 4.11, 95% CI: 1.08, 7.13). CONCLUSIONS: COI indicators were positively associated with youth fitness. Disparities in youth cardiovascular disease risk may be modifiable through community interventions and built environment initiatives targeting select neighborhood factors.

Neighborhood Built Environment Impacts Park Use of Diverse, Low-Income Mothers With Their Children.

Built environment features, including parks, often exacerbate health disparities. We examined built environment perceptions and park use among a population at high risk for negative physical health outcomes: racially diverse, low-income mothers across the United States. Perceived safety from crime and living near a park were associated with more frequent park use for mothers with their children, and neighborhood walkability was linked to longer park visits. However, only 40% of mothers lived within a 10-minute walk of a park, and overall perceptions of walkability and safety from crime were low. To enhance physical activity and health of low-income mothers with their children, investments are needed to close disparities in park access and improve neighborhood safety.

ParkIndex: Validation and application of a pragmatic measure of park access and use.

Composite metrics integrating park availability, features, and quality for a given address or neighborhood are lacking. The purposes of this study were to describe the validation, application, and demonstration of ParkIndex in four diverse communities. This study occurred in Fall 2018 in 128 census block groups within Seattle(WA), Brooklyn(NY), Raleigh(NC), and Greenville County(SC). All parks within a half-mile buffer were audited to calculate a composite park quality score, and select households provided data about use of proximal parks via an online, map-based survey. For each household, the number of parks, total park acreage, and average park quality score within one half-mile were calculated using GIS. Logistic regression was used to identify a parsimonious model predicting park use. ParkIndex values (representing the probability of park use) were mapped for all study areas and after scenarios involving the addition and renovation/improvement of parks. Out of 360 participants, 23.3% reported visiting a park within the past 30 days. The number of parks (OR = 1.36, 95% CI = 1.15-1.62), total park acreage (OR = 1.13, 95% CI = 1.07-1.19), and average park quality score (OR = 1.04, 95% CI = 1.01-1.06) within one half-mile were all associated with park use. Composite ParkIndex values across the study areas ranged from 0 to 100. Hypothetical additions of or renovations to study area parks resulted in ParkIndex increases of 22.7% and 19.2%, respectively. ParkIndex has substantial value for park and urban planners, citizens, and researchers as a common metric to facilitate awareness, decision-making, and intervention planning related to park access, environmental justice, and community health.

Effects of Crime Type and Location on Park Use Behavior.

INTRODUCTION: Crime and the fear of crime can be a barrier to park use, and locations of crimes can have varied effects. Unsafe areas in or around the park, around the residence, or along the route to the park can alter park use behavior. Our study aimed to examine associations between objective measures of types and location of crimes and park use behaviors. METHODS: In 2013 we surveyed a sample (N = 230) of residents in Greensboro, North Carolina, about park use, with responses matched to objective crime and spatial measures. We measured all crimes and violent crimes near home, near the closest park, and along the shortest route between home and park. By using ordered and binary logistic modeling, we examined the relationships between the locations of crime and park use and duration of park visit, park rating, and never visiting parks. Additional models included distance to the closest park. RESULTS: Increased crime in parks and near home was associated with fewer park visits. Greater violent crime in all locations was related to fewer park visits. Park ratings were lower for parks with high violent crime rates. CONCLUSION: Given the importance of parks as settings for outdoor recreation and physical activity, crime may have a detrimental effect on physical activity and, therefore, public health.

Nature Prescriptions for Health: A Review of Evidence and Research Opportunities.

Nature prescription programs have emerged to address the high burden of chronic disease and increasingly sedentary and screen-based lifestyles. This study examines the base of evidence regarding such programs. We conducted a narrative review of published literature using four electronic databases. We included case studies, research design articles, and empirical studies that discussed any type of outdoor exposure or activities initiated by a health-care provider from an outpatient clinic. We examined articles for information on target populations, health outcomes, and structural and procedural elements. We also summarized evidence of the effectiveness of nature prescription programs, and discussed needs and challenges for both practice and research. Eleven studies, including eight empirical studies, have evaluated nature prescription programs with either structured or unstructured formats, referring patients either to nearby parks or to formal outdoor activity programs. Empirical studies evaluate a wide variety of health behaviors and outcomes among the most at-risk children and families. Research is too sparse to draw patterns in health outcome responses. Studies largely tested program structures to increase adherence, or patient follow-through, however findings were mixed. Three published studies explore providers' perspectives. More research is necessary to understand how to measure and increase patient adherence, short and long-term health outcomes for patients and their families, and determinants of provider participation and participation impacts on providers' own health.

Automated High-Frequency Observations of Physical Activity Using Computer Vision.

PURPOSE: To test the validity of the Ecological Video Identification of Physical Activity (EVIP) computer vision algorithms for automated video-based ecological assessment of physical activity in settings such as parks and schoolyards. METHODS: Twenty-seven hours of video were collected from stationary overhead video cameras across 22 visits in nine sites capturing organized activities. Each person in the setting wore an accelerometer, and each second was classified as moderate-to-vigorous physical activity or sedentary/light activity. Data with 57,987 s were used to train and test computer vision algorithms for estimating the total number of people in the video and number of people active (in moderate-to-vigorous physical activity) each second. In the testing data set (38,658 s), video-based System for Observing Play and Recreation in Communities (SOPARC) observations were conducted every 5 min (130 observations). Concordance correlation coefficients (CCC) and mean absolute errors (MAE) assessed agreement between (1) EVIP and ground truth (people counts+accelerometry) and (2) SOPARC observation and ground truth. Site and scene-level correlates of error were investigated. RESULTS: Agreement between EVIP and ground truth was high for number of people in the scene (CCC = 0.88; MAE = 2.70) and moderate for number of people active (CCC = 0.55; MAE = 2.57). The EVIP error was uncorrelated with camera placement, presence of obstructions or shadows, and setting type. For both number in scene and number active, EVIP outperformed SOPARC observations in estimating ground truth values (CCC were larger by 0.11-0.12 and MAE smaller by 41%-48%). CONCLUSIONS: Computer vision algorithms are promising for automated assessment of setting-based physical activity. Such tools would require less manpower than human observation, produce more and potentially more accurate data, and allow for ongoing monitoring and feedback to inform interventions.

Parental Preference for Park Attributes Related to Children's Use of Parks in Low-Income, Racial/Ethnic Diverse Neighborhoods.

Public parks offer free and easy access to spaces for outdoor recreation, which is essential for children's outdoor play and physical activity in low-income communities. Because parks and playgrounds contribute to children's physical, social, and emotional development, it is critical to understand what makes them attractive and welcoming for families with young children. Parents can be a key determinant to children visiting parks, with their preferences influencing whether or not families visit parks in their neighborhoods. Our study examined attributes associated with parental preferences for parks in low-income diverse communities in New York City, New York, and Raleigh-Durham, North Carolina, USA. Parents' responses were grouped into 10 categories using content analysis, with four key preference themes identified: physical attributes, experiences, social environment, and amenities. Physical attributes (i.e., playgrounds, sports fields, green spaces) were most desired among all groups. A significant difference across race/ethnic groups was found in New York but not in Raleigh-Durham. In New York, Latino parents had a strong preference for experience attributes (i.e. safety, safe facilities, cleanliness), which differed from other groups. Examining only Latino parents across both cities, we found no significant difference in preferences between the two cities. Although there is no one-size-fits-all approach to encourage park use, our finding suggests facilities and park safety are modifiable ways local government agencies could design and maintain parks that would be preferred by parents for their children. Future research should examine how neighborhood context may influence parent preferences related to parks.

Neighborhood characteristics associated with park use and park-based physical activity among children in low-income diverse neighborhoods in New York City.

Urban parks provide spaces and facilities for children's physical activity (PA) and can be a free resource in low-income communities. This study examined whether neighborhood characteristics were associated with children's park use and park-based moderate-to-vigorous PA (MVPA) in low-income diverse communities and how associations differed between ethnic groups. Data on park visits and MVPA came from 16,402 children 5-10-years old directly observed using the System for Observing Play and Recreation in Communities in 20 parks in low-income neighborhoods with majority Latino or Asian populations in New York City. Neighborhood characteristics included land use mix (LUM), street audits, crime rates, and an area deprivation index. We employed Poisson and negative binomial models to estimate effects of neighborhood-level variables on the number of children observed in parks and engaging in MVPA, overall and by ethnicity. Results for Asian, Latino, and African American children indicated that higher levels of LUM and pedestrian-friendly streets were associated with greater numbers of children in parks and higher MVPA across all three groups. For Asian and Latino children only, quality of environment was positively associated with MVPA, whereas level of deprivation and crime rates in the surrounding neighborhood were negatively associated with children's park-based MVPA. In contrast, a park's access to public transportation was negatively associated with number of all children observed and engaging in MVPA. Study findings suggest that park-based MVPA interventions can be informed by understanding how neighborhood characteristics facilitate and constrain park use and park-based MVPA.