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The intricate relationship between food systems and health outcomes, known as the food-nutrition-health nexus, intersects with environmental concerns. However, there's still a literature gap in evaluating food systems alongside the global syndemic using the complex systems theory, especially concerning vulnerable populations like children. This research aimed to design a system dynamics model to advance a theoretical understanding of the connections between food systems and the global syndemic, particularly focusing on their impacts on children under five years of age. The framework was developed through a literature review and authors' insights into the relationships between the food, health, and environmental components of the global syndemic among children. The conceptual model presented 17 factors, with 26 connections and 6 feedback loops, categorized into the following 5 groups: environmental, economic, school-related, family-related, and child-related. It delineated and elucidated mechanisms among the components of the global syndemic encompassing being overweight, suffering from undernutrition, and climate change. The findings unveiled potential interactions within food systems and health outcomes. Furthermore, the model integrated elements of the socio-ecological model by incorporating an external layer representing the environment and its natural resources. Consequently, the development of public policies and interventions should encompass environmental considerations to effectively tackle the complex challenges posed by the global syndemic.

This study aimed to describe a quantitative survey conducted with leaders to investigate effective and feasible actions that can be evaluated in computational models to inform policies to promote active mobility based in the city of São Paulo, Brazil. In 2022, an online survey was conducted during the Health Survey in São Paulo (Physical Activity and Environment study), which is monitored by representatives of nongovernmental organizations and public and private sector managers. A questionnaire was elaborated with three questions with 13 alternative answers about actions to promote walking and/or cycling. Leaders should select up to three alternatives based on their potential regarding: (1) effectiveness; (2) feasibility or ease of implementation; and (3) desire to verify tests in computational models to inform policies. The survey was answered by 18 leaders from 16 institutions, comprising 13 (72%) women and 12 (67%) representatives of the third sector, whose average age was 48 years and all had complete higher education. Reducing the speed of motor vehicles was the most cited option in all three questions. Other actions mentioned refer to controlling the traffic of vehicles in central areas, improving pedestrian safety, reducing the distances between homes and places of employment, conducting educational campaigns, and expanding and enhancing structures such as bicycle lanes and sidewalks. The results are relevant to support evidence-based decision-making in public management and to provide subsidies for the development of computational models with a view to promoting active mobility.

This study aimed to systematically review scientific evidence on the barriers and facilitators of physical activity (PA) among the Brazilian population, considering different domains (leisure, travel, work/study, and household). The search was conducted in the MEDLINE/PubMed, ISI Web of Science, SCOPUS, BIREME/LILACS, and APA PsycNET databases and was limited to papers published between 2010 and 2020. A manual search of the Brazilian Journal of Physical Activity & Health was also conducted. The selection process consisted of screening titles and abstracts, followed by the analysis of full texts. Each paper was assessed by two independent reviewers, and when discrepancies arose, a third reviewer was consulted. Leisure, environmental barriers and facilitators were the most investigated domains in the 78 included studies. There was consistency in the positive associations between six different intrapersonal and social facilitators for leisure PA and one environmental factor for travel. There have been a small number of investigations on the work/study and household domains, and future investigations on intrapersonal and social barriers and facilitators in the travel domain are important.

Leisure-time physical activity (LTPA) is associated with access and use of public open spaces. The President João Goulart Elevated Avenue, currently denominated Minhocão, is a facility for leisure activities that is open for people during the night and weekends. The aim of this study was to examine if the prevalence of LTPA among individuals living in the surroundings of Minhocão is different according to proximity to, and use of, the facility. We conducted a cross-sectional study with cluster sampling with people aged ≥18 years who lived in households up to 500 m, and between 501 m and 1500 m of Minhocão. The survey was conducted between December 2017 and March 2019 using an electronic questionnaire. We conducted a bivariate analysis and Poisson regression to examine possible differences in LTPA according to the proximity of residences and use of Minhocão. The analysis used post-stratification weights. A total of 12,030 telephone numbers of people were drawn (≤500 m = 6942; and >500 m to ≤1500 m = 5088). The final sample included 235 residents who returned the questionnaires. There was a higher prevalence of individuals engaging in at least 150 min per week of LTPA among users than non-users (Prevalence Ratio = 2.19, IC95% 1.66 to 2.90), independently of sex, age, education, the distance of houses to nearest accesses and number of barriers. The main five barriers related to the usage of the Minhocão were safety issues in and around the Minhocão, rainy weather, lack of vegetation, and lack of facilities. People who used the park had higher prevalence of all types of LTPA than non-users. The results can serve to inform government decision-making on the future of Minhocão.

Background: This article describes the process and methods used in the development of the first ever Physical Activity Guidelines for the Brazilian Population., Methods: The steering committee established 8 working groups based on other guidelines and the Brazilian agenda for public health and physical activity (PA) promotion: (1) understanding PA; (2) children up to 5 years; (3) children and youth (6-17 y); (4) adults; (5) older adults (60 years and above); (6) physical education at school; (7) pregnant and postpartum women; and (8) people with disabilities. Working groups were formed to (1) synthesize the literature on each topic; (2) conduct workshops with stakeholders, health professionals, researchers, and the public; and (3) prepare a draft chapter for open online consultation., Results: The document provides guidance for the population on the benefits of being active and recommendations regarding the amount (frequency, intensity, and duration) of PA recommended across all chapters. It also includes information on supporting networks for PA., Conclusions: The PA guidelines are widely accessible in Portuguese, including versions in English, Spanish, audiobook, and Braille, and will assist policy makers and professionals from several sectors to promote PA. The ultimate goal is to increase population levels of PA in Brazil.

Background: This article presents the recommendations from the Physical Activity Guidelines for the Brazilian Population., Methods: A steering committee composed of a chair, 6 experts in physical activity, and representatives from the Ministry of Health/Brazil, Pan American Health Organization, Brazilian Society of Physical Activity and Health designed the guidelines, which was implemented by 8 working groups, as follows: (1) understanding physical activity, (2) children up to 5 years old, (3) children and youth from 6 to 17 years old, (4) adults, (5) older adults (60 years and above), (6) physical education at school, (7) pregnant and postpartum women, and (8) people with disabilities. The methodological steps included evidence syntheses, hearings with key stakeholders, and public consultation., Results: Across 8 chapters, the guidelines provide definitions of physical activity and sedentary behavior, informing target groups on types of physical activity, dosage (frequency, intensity, and duration), benefits, and supporting network for physical activity adoption. The guidelines are openly available in Portuguese, Spanish, English, and Braille and in audio versions, with a supplementary guide for health professionals and decision makers, and a report about the preparation and references., Conclusions: The Physical Activity Guidelines for the Brazilian Population provide evidence-based recommendations, being a public-directed resource to contribute to the physical activity promotion in Brazil.

Given the potential of institutional approaches to health promotion, this study sought to identify the countries on the American continent which have national physical activity (PA) guidelines approved by their national health agencies. A scoping review was conducted in May 2019, with a search conducted in five electronic databases, national health agency websites and contacts with members of the Physical Activity Network of the Americas. In all, national PA guidelines were found in ten of the 36 countries surveyed (27.8%), published between 2011 and 2018, the majority being in South American countries (n = 6). All guidelines presented "approaches and strategies for primary health care," "PA recommendations for health," and the "involvement of different PA domains," however, few guidelines addressed "constructed environment and infrastructure" (n = 3), as well as "monitoring and surveillance actions" (n = 5). The conclusion can be drawn that, although few countries on the American continent have guidelines for PA and that the majority of those available address PA in a limited way, new national guidelines, based on the complexity of the determinants, monitoring and consequences of PA are needed to guide and foster policies to promote PA within the population.

Childhood obesity in US Latinx and Latin American populations is a persistent, complex public health issue and, as such, requires solutions grounded on systems science theory and methods. In this paper, we introduce an action-oriented framework to design, implement, evaluate, and sustain whole-of-community systems changes for childhood obesity prevention in US Latinx and Latin American populations. Our framework covers six action steps: (1) foster multisectoral team; (2) map the system, its context, and drivers; (3) envision system-wide changes; (4) effect system-wide changes; (5) monitor, learn, and adapt; and (6) scale and sustain. We also propose 10 principles that put human and environmental rights and systems thinking at the center of these systems-based solutions. For each action step, we provide a list of concrete activities, methods, approaches, and examples that can be used to guide and inform the work needed to achieve the expected outputs. Finally, we discuss how a wider adoption of systems science for childhood obesity prevention among US Latinx and Latin American populations can be encouraged and sustained., (© 2021 The Authors. Obesity Reviews published by John Wiley & Sons Ltd on behalf of World Obesity Federation.)

Background: Sedentary behavior is influenced by contextual, social, and individual factors, including the built environment. However, associations between the built environment and sitting time have not been extensively investigated in countries with economies in transition such as Brazil. The objective of this study is to examine the relationship between sitting-time and access to a mix of destinations for adults from Sao Paulo city, Brazil., Methods: This study uses data from the Health Survey of Sao Paulo. Sedentary behavior was assessed by a questionnaire using two questions: total sitting time in minutes on a usual weekday; and on a usual weekend day. The mix of destinations was measured by summing the number of facilities (comprising bus stops, train/subway stations, parks, squares, public recreation centres, bike paths, primary health care units, supermarkets, food stores, bakeries, and coffee-shops) within 500 m of each participant's residence. Minutes of sitting time in a typical weekday and weekend day were the outcomes and the mix of destinations score in 500 m buffers was the exposure variable. Associations between the mix of destinations and sitting time were examined using multilevel linear regression: these models accounted for clustering within census tracts and households and adjusted for environmental, sociodemographic, and health-related factors., Results: After adjustment for covariates, the mix of destinations was inversely associated with minutes of sitting time on a weekday (β=- 8.8, p=0.001) and weekend day (β=- 6.1, p=0.022). People who lived in areas with a greater mix of destinations had shorter average sitting times., Conclusion: Greater mix of destinations within 500 m of peoples' residences was inversely associated with sitting time on a typical weekday and weekend day. In Latin American cities like Sao Paulo built environments more favorable for walking may contribute to reducing sedentary behavior and prevent associated chronic disease.

Background: Many studies have investigated the association between the built environment and physical activity behavior in urban settings. However, most of the studies conducted in low- and middle-income countries were cross-sectional, which are limited to identify behavioral determinants. We propose a prospective cohort study to verify the relationship between built environment features and leisure-time and transport-related physical activity in adults from Sao Paulo city, Brazil., Methods: Prospective multilevel cohort, denominated "ISA-Physical Activity and Environment". It will build on the Health Survey of Sao Paulo in 2015 ("Inquérito de Saúde de São Paulo (ISA)" in Portuguese). The Health Survey of Sao Paulo, originally designed as a cross-sectional survey, had a multi-stage sample, covering 150 census tracts distributed in five health administrative areas. Data collection was performed by face-to-face interviews until December 2015 and the sample comprised 4043 individuals aged 12 years or more. The ISA-Physical Activity and Environment study will reassess people who are aged 18 years or more in 2020, including telephone and household interviews. The primary outcome will be leisure-time and transport-related physical activity, assessed through the International Physical Activity Questionnaire long version. Exposure variables will be built environment features in the areas participants live and work in the follow-up. Data analysis will include multivariate multilevel linear and logistic models. We will also conduct cost-effectiveness analysis and develop agent-based models to help inform decision-makers. The study will be conducted by an interdisciplinary research team specialized in physical activity epidemiology, nutritional epidemiology, georeferencing applied to health, statistics, agent-based modeling, public health policy, and health economics., Discussion: There are few longitudinal studies on the relationship between the built environment and physical activity behavior in low- and middle-income countries. We believe that the ISA-Physical Activity and Environment study will contribute with important results for the progress of the knowledge in this field and for the implementation of policies that promote leisure-time physical activity and active travel in Sao Paulo and similar cities across the world.

Background: Exposure to air pollution and physical inactivity are both significant risk factors for non-communicable diseases (NCDs). These risk factors are also linked so that the change in exposure in one will impact risks and benefits of the other. These links are well captured in the active transport (walking, cycling) health impact models, in which the increases in active transport leading to increased inhaled dose of air pollution. However, these links are more complex and go beyond the active transport research field. Hence, in this study, we aimed to summarize the empirical evidence on the links between air pollution and physical activity, and their combined effect on individual and population health., Objectives and Methods: We conducted a non-systematic mapping review of empirical and modelling evidence of the possible links between exposure to air pollution and physical activity published until Autumn 2019. We reviewed empirical evidence for the (i) impact of exposure to air pollution on physical activity behaviour, (ii) exposure to air pollution while engaged in physical activity and (iii) the short-term and (iv) long-term health effects of air pollution exposure on people engaged in physical activity. In addition, we reviewed (v) public health modelling studies that have quantified the combined effect of air pollution and physical activity. These broad research areas were identified through expert discussions, including two public events performed in health-related conferences., Results and Discussion: The current literature suggests that air pollution may decrease physical activity levels during high air pollution episodes or may prevent people from engaging in physical activity overall in highly polluted environments. Several studies have estimated fine particulate matter (PM 2.5 ) exposure in active transport environment in Europe and North-America, but the concentration in other regions, places for physical activity and for other air pollutants are poorly understood. Observational epidemiological studies provide some evidence for a possible interaction between air pollution and physical activity for acute health outcomes, while results for long-term effects are mixed with several studies suggesting small diminishing health gains from physical activity due to exposure to air pollution for long-term outcomes. Public health modelling studies have estimated that in most situations benefits of physical activity outweigh the risks of air pollution, at least in the active transport environment. However, overall evidence on all examined links is weak for low- and middle-income countries, for sensitive subpopulations (children, elderly, pregnant women, people with pre-existing conditions), and for indoor air pollution., Conclusions: Physical activity and air pollution are linked through multiple mechanisms, and these relations could have important implications for public health, especially in locations with high air pollution concentrations. Overall, this review calls for international collaboration between air pollution and physical activity research fields to strengthen the evidence base on the links between both and on how policy options could potentially reduce risks and maximise health benefits., (Copyright © 2020 World Health Organization. Published by Elsevier Ltd.. All rights reserved.)

The difficulty in achieving ideal coverage rates with the influenza vaccine in Brazil and the growing wave of antivaccine movements in the world point to the need for a more in-depth understanding of the individual determinants of to this vaccine uptake. The Health Belief Model, a theoretical model that aims to explain and predict health-related behaviors, suggests that individual beliefs influence the adoption of health-related behaviors. The objective of this study was a cross-cultural adaptation of an instrument to assess predictors of influenza vaccine uptake in Brazilian adults. The authors conducted translation, back-translation, face validity, and a survey for construct validity. They also analyzed the factors associated with influenza vaccine uptake in 2017. An instrument originally with seven domains was identified and selected. In the factor analysis, four of the model's seven constructs were validated: Susceptibility, Barriers, Cues to action, and Self-efficacy. In the survey with 396 persons, 59.3% reported having received the influenza vaccine in the last campaign in 2017. Female sex, age > 50 years, pregnancy, vaccination in private healthcare services, hepatitis B vaccination, and influenza vaccination prior to 2017 were associated with vaccination in 2017. In the final logistic regression model, perceived Barriers appeared as a strong factor for non-vaccination, while Cues to action increased the odds of vaccination.

Urban transportation is an important determinant of health and environmental outcomes, and therefore essential to achieving the United Nation's Sustainable Development Goals. To better understand the health impacts of transportation initiatives, we conducted a systematic review of longitudinal health evaluations involving: a) bus rapid transit (BRT); b) bicycle lanes; c) Open Streets programs; and d) aerial trams/cable cars. We also synthesized systems-based simulation studies of the health-related consequences of walking, bicycling, aerial tram, bus and BRT use. Two reviewers screened 3302 unique titles and abstracts identified through a systematic search of MEDLINE (Ovid), Scopus, TRID and LILACS databases. We included 39 studies: 29 longitudinal evaluations and 10 simulation studies. Five studies focused on low- and middle-income contexts. Of the 29 evaluation studies, 19 focused on single component bicycle lane interventions; the rest evaluated multi-component interventions involving: bicycle lanes (n = 5), aerial trams (n = 1), and combined bicycle lane/BRT systems (n = 4). Bicycle lanes and BRT systems appeared effective at increasing bicycle and BRT mode share, active transport duration, and number of trips using these modes. Of the 10 simulation studies, there were 9 agent-based models and one system dynamics model. Five studies focused on bus/BRT expansions and incentives, three on interventions for active travel, and the rest investigated combinations of public transport and active travel policies. Synergistic effects were observed when multiple policies were implemented, with several studies showing that sizable interventions are required to significantly shift travel mode choices. Our review indicates that bicycle lanes and BRT systems represent promising initiatives for promoting population health. There is also evidence to suggest that synergistic effects might be achieved through the combined implementation of multiple transportation policies. However, more rigorous evaluation and simulation studies focusing on low- and middle-income countries, aerial trams and Open Streets programs, and a more diverse set of health and health equity outcomes is required., Competing Interests: Declaration of competing interests The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Studies on the impact of counterfactual scenarios of physical activity on premature deaths from non-communicable diseases (NCDs) are sparse in the literature. We estimated preventable premature deaths from NCDs (diabetes, ischemic heart disease, stroke, and breast and colon cancers) in Brazil by increasing population-wide physical activity (i) to theoretical minimum risk exposure levels; (ii) reaching the physical activity recommendation; (iii) reducing insufficient physical activity by 10%; and (iv) eliminating the gender differences in physical activity., Methods: Preventable fractions were estimated using data from a nationally representative survey, relative risks from a meta-analysis and number of premature deaths (30-69 years) from the Brazilian Mortality Information System., Results: Physical activity could potentially avoid up to 16 700 premature deaths from NCDs in Brazil, corresponding to 5.75 and 3.23% of premature deaths from major NCDs and of all-causes, respectively. Other scenarios suggested the following impact on premature deaths: reaching physical activity recommendation (5000 or 1.74% of major NCDs); 10% reduction in insufficient physical activity (500 or 0.17% of major NCDs); eliminating gender differences in physical activity (1000 or 0.33% of major NCDs)., Conclusions: Physical activity may play an important role to reduce premature deaths from NCD in Brazil., (© The Author(s) 2018. Published by Oxford University Press on behalf of Faculty of Public Health.)

Introduction: Most interventions aiming to promote leisure-time physical activity (LTPA) at population level showed small or null effects. Approaching the problem from a systems science perspective may shed light on the reasons for these results. We developed an agent-based model to explore how the interactions between psychological attributes and built and social environments may lead to the emergence and evolution of LTPA patterns among adults., Methods: The modeling process consisted of four stages: (1) conceptual model development, (2) formulation of the agent-based model, (3) parametrization and calibration, and (4) consistency and sensitivity analyses. The model represents a stylized community containing two types of agents: persons and LTPA sites. Persons interact with each other (proximal network and perceived community) and with the built environment (LTPA sites) over time. Decision-making is based on the person's intention to practice LTPA, conditioned to the perceived environment. Each iteration is equivalent to one week and we assessed a period of 10 years., Results: The model was able to reproduce population temporal trends of intention and LTPA reported in the literature. Sensitivity analyses indicated that population patterns and trends of intention and LTPA were highly influenced by the relationship between a person's behavior in the preceding week and his current intention, the person's access to built and social environment, and the density of LTPA sites., Conclusions: The proposed agent-based model is suitable to explore the emergence and evolution of LTPA patterns among adults, considering the dynamic interaction between individuals' psychological attributes and the built and social environments in which they live. The model is available at https://doi.org/10.17605/OSF.IO/J2KAS .

This study aims to describe a local network for physical activity promotion and identify factors associated to collaboration or partnership ties between its actors. The study was carried out in a district of São Paulo, Brazil. Thirty-two actors responsible for policies, programs, and initiatives to promote physical activity within the district were interviewed from June to December 2012. Interviews included information about the actors' attributes and their relationships with the other actors. Network analysis techniques were used to describe and analyze the structure of the network. Thirty-two actors maintained 179 relationships among themselves (density = 0.18), of which 46% were reciprocal. Four in 10 relationships did not extend beyond information exchange. Forty-six relationships were classified as collaborations or partnerships (density = 0.09), of which 40% were concentrated on one actor of the public sector. To perceive institutional structure and bureaucracy as limiting factors to networking has been positively associated with new collaboration or partnership ties (OR = 2.37; 95%CI: 1.2-5.50). Understanding the structure of the network may empower the actors and foster self-management, facilitating the identification and decision, in a collaborative way, in which new relationships may have greater impact in the physical activity promotion within the district.

Background: Physical activity is associated with lower risk of colon and breast cancers. Herein we estimated preventable fractions of colon and breast cancers in Brazil by increasing population-wide physical activity to different counterfactual scenarios., Methods: We used data from a representative national survey in Brazil and corresponding relative risks of colon and postmenopausal breast cancers from a meta-analysis. Estimated cancer incidence was retrieved from GLOBOCAN and Brazilian National Cancer Institute. Five counterfactual scenarios for physical activity were considered: (i) theoretical minimum risk exposure level (≥8,000 metabolic equivalent of tasks-minute/week - MET-min/week); (ii) physical activity recommendation (≥600 MET-min/week); (iii) a 10% reduction in prevalence of insufficient physical inactivity (<600 MET-min/week); (iv) physical activity level in each state equals the most active state in Brazil; (v) closing the gender differences in physical activity., Results: About 19% (3,630 cases) of colon cancers and 12% (6,712 cases) of postmenopausal breast cancers could be prevented by increasing physical activity to ≥8,000 MET-min/week. Plausible counterfactual scenarios suggested the following impact on cancer prevention: reaching physical activity recommendation: 1.7% (1,113 cases) of breast and 6% (1,137 cases) of colon; 10% reduction in physical inactivity prevalence: 0.2% (111 cases) of breast and 0.6% (114 cases) of colon; most active state scenario: 0.3% (168 cases) of breast and 1% (189 cases) of colon; reducing gender differences in physical activity: 1.1% (384 cases) of breast and 0.6% (122 cases) of colon., Conclusions: High levels of physical activity are required to achieve a sizable impact on breast and colon cancer prevention in Brazil., (Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: Street imagery is a promising and growing big data source providing current and historical images in more than 100 countries. Studies have reported using this data to audit road infrastructure and other built environment features. Here we explore a novel application, using Google Street View (GSV) to predict travel patterns at the city level., Methods: We sampled 34 cities in Great Britain. In each city, we accessed 2000 GSV images from 1000 random locations. We selected archived images from time periods overlapping with the 2011 Census and the 2011-2013 Active People Survey (APS). We manually annotated the images into seven categories of road users. We developed regression models with the counts of images of road users as predictors. The outcomes included Census-reported commute shares of four modes (combined walking plus public transport, cycling, motorcycle, and car), as well as APS-reported past-month participation in walking and cycling., Results: We found high correlations between GSV counts of cyclists ('GSV-cyclists') and cycle commute mode share (r = 0.92)/past-month cycling (r = 0.90). Likewise, GSV-pedestrians was moderately correlated with past-month walking for transport (r = 0.46), GSV-motorcycles was moderately correlated with commute share of motorcycles (r = 0.44), and GSV-buses was highly correlated with commute share of walking plus public transport (r = 0.81). GSV-car was not correlated with car commute mode share (r = -0.12). However, in multivariable regression models, all outcomes were predicted well, except past-month walking. The prediction performance was measured using cross-validation analyses. GSV-buses and GSV-cyclists are the strongest predictors for most outcomes., Conclusions: GSV images are a promising new big data source to predict urban mobility patterns. Predictive power was the greatest for those modes that varied the most (cycle and bus). With its ability to identify mode of travel and capture street activity often excluded in routinely carried out surveys, GSV has the potential to be complementary to new and traditional data. With half the world's population covered by street imagery, and with up to 10 years historical data available in GSV, further testing across multiple settings is warranted both for cross-sectional and longitudinal assessments.

Despite the increasing body of evidences on the factors influencing leisure-time physical activity, our understanding of the mechanisms and interactions that lead to the formation and evolution of population patterns is still limited. Moreover, most frameworks in this field fail to capture dynamic processes. Our aim was to create a dynamic conceptual model depicting the interaction between key psychological attributes of individuals and main aspects of the built and social environments in which they live. This conceptual model will inform and support the development of an agent-based model aimed to explore how population patterns of LTPA in adults may emerge from the dynamic interplay between psychological traits and built and social environments. We integrated existing theories and models as well as available empirical data (both from literature reviews), and expert opinions (based on a systematic expert assessment of an intermediary version of the model). The model explicitly presents intention as the proximal determinant of leisure-time physical activity, a relationship dynamically moderated by the built environment (access, quality, and available activities) - with the strength of the moderation varying as a function of the person's intention- and influenced both by the social environment (proximal network's and community's behavior) and the person's behavior. Our conceptual model is well supported by evidence and experts' opinions and will inform the design of our agent-based model, as well as data collection and analysis of future investigations on population patterns of leisure-time physical activity among adults.

The available strategy for controlling the diseases transmitted by Aedes ægypti (dengue fever, Zika, and chikungunya) relies on continued community participation. Despite slogans emphasizing how easy it should be, no country has achieved it since the seventies. To better investigate potentially sustainable interventions, we developed a systemic model based on a multidisciplinary approach, integrating as deeply as possible specialized knowledge and field experience. The resulting model is composed of 4 external and 8 internal subsystems and 31 relationships, consistent with the literature and checked over multiple iterations with specialists of the many areas. We analyzed the model and the main feedback loops responsible for the system's stability, searching for possible interventions that could shift the existing balance. We suggest the introduction of 1 more player, the local primary health care structure, with the potential to change the undesired equilibrium. The health agents in the areas are the first to detect disease cases, and they could stimulate individuals to inform about potential mosquitoes' breeding sites and bring timely information to the vector-control program. Triggering such an action could introduce changes in people's attitude through a positive feedback loop in the desired direction.

Objective: To assess the effect of interventions on the levels of physical activity of healthy adults, users of the Brazilian Unified Health System and attended by the Family Health Strategy., Methods: Non-randomized experimental study with 157 adults allocated in three groups: 1) physical exercise classes (n = 54), 2) health education (n = 54), 3) control (n = 49). The study lasted for18 months, with 12 months of interventions and six months of follow-up after intervention. Assessments took place at the beginning, in the 12 months, and in the 18 months of study. Physical activity has been assessed by questionnaires and accelerometry. For the analyses, we have used the intention-to-treat principle and generalized estimating equations., Results: After 12 months, both intervention groups have increased the minutes of weekly leisure time physical activity and annual scores of physical exercise, leisure and transport-related physical activity. The exercise class group has obtained the highest average annual physical exercises score when compared to the other groups (p < 0.001). In the follow-up period, the exercise class group reduced its annual score (average: -0.3; 95%CI -0.5--0.1), while the health education group increased this score (average: 0.2; 95%CI 0.1-0.4). There have been no differences in the levels of physical activity measured by accelerometry., Conclusions: The interventions have been effective in increasing the practice of physical activity. However, we have observed that the health education intervention was more effective for maintaining the practice of physical activity in the period after intervention. We recommend the use of both interventions to promote physical activity in the Brazilian Unified Health System, according to the local reality of professionals, facilities, and team objectives., Objetivo: Avaliar o efeito de intervenções nos níveis de atividade física de adultos saudáveis, usuários do Sistema Único de Saúde e atendidos pela Estratégia de Saúde da Família., Métodos: Estudo experimental, não randomizado, com 157 adultos alocados em três grupos: 1) classes de exercícios físicos (n = 54); 2) educação em saúde (n = 54); 3) controle (n = 49). O estudo teve duração de 18 meses, sendo 12 meses de intervenções e seis meses de acompanhamento pós-intervenção. As avaliações ocorreram no início, nos 12 e nos 18 meses de estudo. A atividade física foi avaliada por questionários e por acelerometria. Para as análises, utilizaram-se o princípio de intenção de tratar e equações de estimativas generalizadas., Resultados: Após 12 meses, ambos os grupos de intervenção aumentaram os minutos semanais de atividade física no lazer e os escores anuais de exercícios físicos, de lazer e de deslocamento. O grupo das classes de exercícios físicos obteve maior média de escore anual de exercícios físicos em comparação com os outros grupos (p < 0,001). No período pós-intervenção, o grupo de classes de exercícios físicos reduziu o escore anual de exercícios físicos (média: -0,3; IC95% -0,5--0,1), enquanto o grupo de educação em saúde aumentou este escore (média: 0,2; IC95% 0,1-0,4). Não houve diferenças nos níveis de atividade física mensurados por acelerometria., Conclusões: As intervenções foram efetivas para aumentar a prática de atividade física. No entanto, observou-se que a intervenção de educação em saúde foi mais efetiva para a manutenção da prática de atividade física no período pós-intervenção. Recomenda-se a utilização de ambas as intervenções para a promoção da atividade física no Sistema Único de Saúde, de acordo com as realidades locais de profissionais, instalações e objetivos das equipes.

Introduction: Recent studies have shown that sitting time is associated with increased risk of all-cause mortality, independent of moderate to vigorous physical activity. Less is known about the population-attributable fraction for all-cause mortality associated with sitting time, and the gains in life expectancy related to the elimination of this risk factor., Methods: In November 2015, data were gathered from one published meta-analysis, 54 adult surveys on sitting time distribution (from 2002 to 2011), in conjunction with national statistics on population size, life table, and overall deaths. Population-attributable fraction for all-cause mortality associated with sitting time >3 hours/day was estimated for each country, WHO regions, and worldwide. Gains in life expectancy related to the elimination of sitting time >3 hours/day was estimated using life table analysis., Results: Sitting time was responsible for 3.8% of all-cause mortality (about 433,000 deaths/year) among those 54 countries. All-cause mortality due to sitting time was higher in the countries from the Western Pacific region, followed by European, Eastern Mediterranean, American, and Southeast Asian countries. Eliminating sitting time would increase life expectancy by 0.20 years in those countries., Conclusions: Assuming that the effect of sitting time on all-cause mortality risk is independent of physical activity, reducing sitting time plays an important role in active lifestyle promotion, which is an important aspect of premature mortality prevention worldwide., (Copyright © 2016 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.)