Can Population Levels of Physical Activity be Increased? Global Evidence and Experience

Abstract

Physical inactivity is one of the most important contributors to the global burden of disease and has become a global public health priority. We review the evidence on physical activity (PA) interventions, actions, and strategies that have the greatest potential to increase PA at the population level. Using the socio-ecological framework to conceptualize PA interventions, we show that PA can be targeted at multiple levels of influence and by multiple sectors outside the health system. Examples of promoting PA on a national scale are presented from Finland, Canada, Brazil, and Colombia. A strong policy framework, consistent investment in public health programs, multi-sectoral support and actions, and good surveillance characterize each of these success stories. Increasing PA globally will depend on successfully applying and adapting these lessons around the world taking into account country, culture, and context.

INTRODUCTION

Physical inactivity accounts for more than five million premature deaths each year, making it one of the most important contributors to the global burden of disease.¹ Public health policy is beginning to be informed by this fact. Physical activity (PA) is prominently featured in the World Health Organization’s Global Action Plan for the Prevention and Control of Non-Communicable Diseases (NCDs) 2013–2020 and the targets and indicators within a global monitoring framework for NCDs.^2,3 Many countries have national public health plans with specific objectives that support and encourage physical activity, including the United States (US), United Kingdom, Brazil, Colombia, Australia, and India.^4–9 The ubiquity of inactivity as a public health challenge was made clear in The Lancet series on PA in 2012.^1,10–14 Nearly one third of adults are inactive worldwide¹⁰ and there is a growing evidence-base on the correlates and determinants of physical activity¹¹ and effective interventions to increase PA¹². However, substantial gaps in the evidence remain, especially related to interventions in low and middle-income countries (LMIC) and interventions at a scale beyond the community-level.¹³

In this paper we critically review the evidence on PA interventions, actions, and strategies that have the greatest potential to increase PA at the population level. We will first define a framework for understanding ways to change population levels of PA, then summarize the published systematic reviews on PA interventions, highlight four examples of promoting PA at a national scale, and finally synthesize recommendations for public health policy, research, and practice given our current understanding of the field.

Increasing PA at the population level depends on several factors: the efficacy and effectiveness of the chosen public health and clinical interventions; supportive policy, environments, and planned actions in sectors other than public health and medicine; the population reach of these actions; continuity; scalability; secular trends in key domains such as the economy, technology, and politics; and country, culture, and context.¹³ In other words, PA promotion is a true public health activity fitting well within classic definitions such as those from Last’s A Dictionary of Public Health¹⁵ (“An organized activity of society to promote, protect, improve, and, when necessary, restore the health of individuals, specified groups, or the entire population.”¹⁶), and the Institute of Medicine report The Future of Public Health¹⁷ (“Public Health is organized community efforts aimed at the prevention of disease and promotion of health. Its mission is the fulfillment of society’s interest in assuring conditions in which people can be healthy.”¹⁷).

Successful PA promotion is also characterized by a balance between a strong science base (i.e., evidence-based reviews) and artful application of that science. This blending of the science and art of PA promotion relies on scientific studies, quantitative data, qualitative data, professional judgment, and timing. Again, matching nicely with our understanding of how evidence-based public health (“the process of integrating science-based interventions with community preferences to improve population health”¹⁸) should guide modern public health policy and practice. A key concept in each of these definitions is that public health is population health. A seemingly obvious corollary to this is that global public health must of necessity be especially focused on understanding how to best deliver public health strategies addressing the most important causes of disease and disability to large populations. In reality, this is often not the case. Global public health has been slow to adapt to the triple transition (epidemiologic, demographic, and lifestyle) that has shifted the center of gravity of the global burden of disease to NCDs in LMIC.^19–21 Until quite recently this has also been the case for public health research and programs for physical activity, with the bulk of the evidence and most of the best examples of national plans and policies for PA coming from a handful of high-income countries.^4,5,8,13,14 However, as we will see from recently published evidence-based reviews and our four case studies, research, policy, and programs for PA are also becoming a priority in middle-income countries.

EVIDENCE-BASED REVIEWS

There is a large and growing body of evidence on the effectiveness of PA interventions. Systematic reviews have been conducted using a variety of evidence-based constructs, and these reviews themselves were recently reviewed and summarized in The Lancet¹². We will briefly summarize the results of the key evidence-based reviews and attempt to place them in a socio-ecological framework in order to better understand the totality of the evidence for effectiveness of PA interventions. The United States Guide to Community Preventive Services²² (“the Community Guide” http://www.thecommunityguide.org), the Guide to Clinical Preventive Services²³ (“the Clinical Guide” http://www.ahrq.gov/professionals/clinicians-providers/guidelines-recommendations/guide/), and the United Kingdom National Institute for Health and Care Excellence (NICE)²⁴ (http://www.nice.org.uk/) have been among the most comprehensive review processes to date^25–28. The clinical interventions reviewed in the Clinical Guide and community-based and health system-based interventions reviewed by the Community Guide have been used by researchers and practitioners to guide health promotion and disease prevention efforts in both clinical and community settings. In recent years, the Community Guide process has been culturally adapted to review PA promotion and obesity prevention interventions in Latin America. The Guide for Useful Interventions for PA in Brazil and Latin America (Project GUIA)²⁹ synthesized the evidence for PA interventions in Latin America (http://www.projectguia.org/en/), and the Guide to Obesity Prevention in Latin America and US (Project GOL)³⁰ synthesized the evidence for diet and PA interventions for obesity treatment or prevention among Latinos in the US and Latin America (http://www.sdprc.net/research/other-projects/project-gol/). Both collaborations evaluated interventions based on criteria from the Community Guide.

Across the existing models for evaluating PA interventions, there are several major categories for conceptualizing intervention approaches, including behavioral and social, campaigns and informational, health-care based, as well as environmental and policy approaches. In a recent review in The Lancet, these approaches were found to be effective at increasing PA across various ages, social groups, communities, and countries.¹²

Classifying interventions based on the approach applied to increase PA is useful for evaluating similar interventions; however, this method of conceptualization is not based on any theoretical framework. In fact, few reviews of strategies for promoting health behaviors use a theoretical framework for conceptualizing interventions. To address this gap, we organized the aforementioned approaches for PA promotion within the theoretical framework of the socio-ecological model (SEM), which posits that behavior is influenced by factors that co-exist and interact at multiple levels³¹. The key levels of influence include the intrapersonal (individual), interpersonal, community/organizational, and environmental/policy levels (Figure 1). The notion behind the SEM is that because factors that influence behavior do not act alone, a multilevel approach is deemed to be more effective at behavior change than one that targets only one level.^31,32

Figure 1.

Mapping physical activity intervention strategies on the Socio-Ecological Model.

We searched for reviews of PA interventions published until June 2014 including Community Guide, Project GUIA, Project GOL, NICE, and the Cochrane Collaboration, and attempted to conceptualize the interventions reviewed according to the SEM. Details of the reviews can be found elsewhere^{27,33,28,34–38}.

The results of our review show sufficient to strong evidence for interventions targeting at least one level of influence of the SEM (Table 1). At the intrapersonal level, individually-adapted health behavior interventions were effective at increasing PA levels among overweight/obese Latino adults, pointing to the potential of these interventions for obesity treatment among this population group when combined with dietary improvement efforts. Healthcare-based interventions delivered by health professionals (e.g., counseling) also had positive effects on increasing PA among patients,²⁶ indicating primary care practitioners have an important role in promoting PA at the individual level. Professional advice or counseling can also be enhanced with additional education and support from community-based and healthcare-system based programs to assist practitioners in meeting the health needs of their patients.

Table 1.

Review of Strategies for Increasing Physical Activity by Level of Influence of the Socio-ecological Model

Level of Influence and Strategy	Description	Sources	Target populationand setting	Findings(no. studies included)
Intrapersonal
Individually adapted health behavior change	Education on behavioral skills: goal setting and monitoring of progress, building social support, behavioral reinforcement, problem solving, prevention of relapse into sedentary behavior, etc.	Kahn et al., 200227 Hoehner et al., 200833 Holub et al., 201335	1.1Adults in the US and Australia 2.1N/A 3.1Overweight/obese Latino adults in the US 3.2Overweight/obese adults in Mexico & Brazil 3.3Latino children in the US and Latin America	1.1.1Strong evidence for recommendation (n=18) 2.1.1Insufficient evidence from Latin America for recommendation (n=0) 3.1.1Strong evidence to recommend interventions combining PA and healthy eating/nutrition for obesity treatment (n=14) 3.2.1Sufficient evidence to recommend interventions combining PA and healthy eating/nutrition for obesity treatment (n=9) 3.3.1Insufficient evidence to recommend interventions focused on PAalone for obesity prevention (n=2) or treatment (n=0) 3.3.2Insufficient evidence to recommend interventions combining PAand healthy eating/nutrition for obesity prevention (n=2) or treatment (n=8)
Classroom-based health education focused on providing information	Education on skills development for adopting healthier behaviors; topics vary	Kahn et al., 200227 Hoehner et al., 200833 Biddle, Braithwaite, & Pearson, 201438	1.1Children & adolescents in the US 2.1Children & adolescents in Brazil and US-Mexico border 3.1Young girls in the US and other countries	1.1.1Insufficient evidence for recommendation (n=10) 2.1.1Insufficient evidence for recommendation (n=3) 3.1.1Recommended interventions targeting girls only and those that used educational (n=9) and multicomponent strategies (n=9) based on small but significant effects
Classroom-based education focused on reducing television viewing and video game playing	Education on reducing screen time (e.g., TV)	Kahn et al., 200227 Hoehner et al., 200833	1.1Children & adolescents in the US 2.1N/A	1.1.1Insufficient evidence for recommendation (n=3) 2.1.1Insufficient evidence from Latin America for recommendation (n=0)
College-based physical education/health education	Didactic and behavioral education on setting long-term behavioral patterns for physical activity	Kahn et al., 200227 Hoehner et al., 200833	1.1Young adults in the US 2.1N/A	1.1.1Insufficient evidence for recommendation (n=2) 2.1.1Insufficient evidence from Latin America for recommendation (n=0)
Healthcare-based	Interventions to improve PAamong patients in the primary care or health clinic setting; interventions are delivered by health professionals (e.g., psychologist, licensed nutritionist, licensed dietician, and physician)	NICE, 200626 Orrow et al., 201237 Holub et al., 201335	1.1Adults in Australia, New Zealand, US, UK, & Canada 2.1Adults and older populations in the UK, New Zealand, US, Canada, Switzerland, Australia, & Netherland 3.1Overweight/obese children in Brazil & Mexico 3.2Overweight/obese children in the US 3.3Adults in the US and Latin America	1.1.1Recommended based on evidence showing moderate increases in PA(n=11) 2.1.1Recommended based on small to medium positive intervention effects at follow up (n=13); insufficient evidence to recommend exercise referral schemes over advice or counseling interventions (n=3) 3.1.1Sufficient evidence from Latin America to recommend interventions combining PA and healthy eating/nutrition for obesity treatment in children (n=3) 3.2.1Insufficient evidence from the US to recommend interventions combining PA and healthy eating/nutrition for obesity treatment in children (n=2) 3.3.1Insufficient evidence from the US (n=5) and Latin America (n=1) to recommend interventions combining PA and healthy eating/nutrition for obesity treatment in adults 3.3.2Insufficient evidence to recommend interventions focused on PAalone for obesity prevention (n=1) or treatment (n=1)
Interpersonal
Family-based social support	Joint (with family) or separate education on health, goal-setting, problem solving, family behavioral change	Kahn et al., 200227 Hoehner et al., 200833 Holub et al., 201335	1.1Families in the US & Greece 2.1N/A 3.1Latino children in the US and Latin America 3.2Latino adults in the US and Latin America	1.1.1Insufficient evidence for recommendation (n=11) 2.1.1Insufficient evidence for recommendation from Latin America (n=0) 3.1.1Insufficient evidence to recommend interventions combining PA and healthy eating/nutrition for obesity prevention (n=3) or treatment (n=4) among children 3.1.2Insufficient evidence to recommend interventions focused on PA alone for obesity prevention (n=0) or treatment (n=0) among children 3.2.1Insufficient evidence to recommend interventions combining PA and healthy eating/nutrition for obesity prevention (n=3) or treatment (n=1) among adults 3.2.2Insufficient evidence to recommend interventions focused on PA alone for obesity prevention (n=0) or treatment (n=0) among adults
Nonfamily social support	Building, strengthening, and maintaining social networks that support PA behavior change (e.g., buddy system and walking groups)	Kahn et al., 200227 Hoehner et al., 200833	1.1Adults in the US, Canada, & Australia 2.1Adults in Colombia & US-Mexico border	1.1.1Strong evidence for recommendation (n=9) 2.1.1Insufficient evidence for recommendation (n=2)
Community/Organizational
School-based physical education	Enhanced school physical education (PE): improvements to the curriculum to increase amount spent in moderate or vigorous PAduring PE classes	Hoehner et al., 200833 Lavelle, Mackay, & Pell, 201236 Holub et al., 201335 Lonsdale et al., 201334	1.1Children in Brazil, Chile, & US-Mexico border 2.1Children in Europe, US, Thailand, China, India, Singapore, Australia, Egypt 3.1Latino children in the US 3.2Children in Mexico, Brazil, & Chile 4.1Children in the US, UK, Belgium, & Australia	1.1.1Strong evidence for recommendation (n=5) 2.1.1Recommended interventions focused on PA alone or in combination with dietary change to reduce body mass index (n=34) 3.1.1Sufficient evidence to recommend interventions combining PA and healthy eating/nutrition for obesity prevention (n=8) but insufficient evidence for obesity treatment (n=4) 3.2.1Sufficient evidence to recommend interventions focused on PA alone for obesity prevention (n=3) but insufficient evidence for obesity treatment (n=2) 4.1.1Strong evidence for recommendation (n=14)
Workplace-based	Interventions at the worksite focused on increasing PA among employees (e.g., reduced gym membership fees, supervised exercise, and motivational/educational sessions)	Conn et al., 200964 Holub et al., 201335	1.1Adults in the US, Australia, & New Zealand 2.1Latino adults in the US 2.2Adults in Latin America	1.1.1Evidence inconsistent but some interventions showed improvements in PA(n=138) 2.1.1Insufficient evidence from US to recommend interventions focused on PA alone for obesity prevention (n=0) or treatment (n=0) among Latino adults 2.1.2Insufficient evidence from US to recommend interventions combining PA and healthy eating/nutrition for obesity prevention (n=1) or treatment (n=1) among Latino adults 2.2.1Insufficient evidence from Latin America to recommend interventions focused on PA alone for obesity prevention (n=1) or treatment (n=0) 2.2.2Insufficient evidence from Latin America to recommend interventions combining PAand healthy eating/nutrition for obesity prevention (n=1) or treatment (n=1)
Community-wide campaigns	Multicomponent informational approaches (e.g., social support, health education) involving many community sectors	Kahn et al., 200227 Hoehner et al., 200833	1.1Adults in the US, Sweden, Denmark, Australia, Scotland, Wales 2.1Adults in Brazil	1.1.1Strong evidence for recommendation (n=10) 2.1.1Insufficient evidence for recommendation (n=1)
PA classes in community settings	Regular, structured exercise group classes that involve some educational component	Hoehner et al., 200833	1.1Adults in Brazil and Chile	1.1.1Insufficient evidence for recommendation (n=5)
Mass media campaigns	Delivery of messages on PA via mass media (newspapers, radio, TV, websites, etc.)	Kahn et al., 200227 Hoehner et al., 200833	1.1Adults in the US and Australia 2.1N/A	1.1.1Insufficient evidence for recommendation (n=3) 2.1.1Insufficient evidence from Latin America for recommendation (n=0)
Delivery of short physical activityrelated messages	Delivery of short physical activity-related educational and motivational messages	Hoehner et al., 200833	1.1Women in Brazil	1.1.1Insufficient evidence for recommendation (n=1)
Physical and policy environment
“Point of decision” prompts	Motivational signs placed in/near stairwell or base of elevators to encourage stair use	Kahn et al., 200227 Hoehner et al., 200833	1.1Individuals in the US, England, & Scotland 2.1Individuals in the US-Mexico border	1.1.1Sufficient evidence for recommendation (n=6) 2.1.1Insufficient evidence for recommendation (n=1)
Creation of or enhanced access to places for PA combined with activities in informational outreach	Changing local environment to provide opportunities for PA (e.g., walking trails and building exercise facilities)	Kahn et al., 200227 Hoehner et al., 200833	1.1Adults in the US 2.1N/A	1.1.1Strong evidence for recommendation (n=10) 2.1.1Insufficient evidence from Latin America for recommendation (n=0)
Community-scale urban design and land-use policies and practices	Changing physical environment of urban areas to support PA(e.g., proximity of residential areas to stores/school/work/rec reational areas, connectivity of sidewalks, and aesthetics of environment)	Heath et al. 200628 Hoehner et al., 200833	1.1Adults in the US and Canada 2.1N/A	1.1.1Sufficient evidence for recommendation (n=12) 2.1.1Insufficient evidence from Latin America for recommendation (n=0)
Street scale urban design and land use policies and practices	Changing physical environment of small geographic areas to support PA(e.g., building codes, roadway design standards, improved street lighting, and use of traffic calming approaches)	Heath et al., 200628 Hoehner et al., 200833	1.1Adults in the US, England, Canada, Australia, Belgium, & Germany 2.1N/A	1.1.1Sufficient evidence for recommendation (n=6) 2.1.1Insufficient evidence from Latin America for recommendation (n=0)
Community-wide policies and planning	Multicomponent approaches to remove environmental/institutional barriers to physical activity; may involve many community sectors	Hoehner et al., 200833 NICE, 200825	1.1Women in Colombia 2.1Adults in the US, Germany, Netherlands, & Finland	1.1.1Insufficient evidence for recommendation (n=1) 2.1.1Evidence found suggesting positive association between PA and national policies on health and physical activity, transport, and planning (n=3)

PA, physical activity

At the interpersonal level, there was strong evidence for recommending nonfamily social support strategies for promoting PA among adults in high-income settings (i.e., US, Canada, and Australia) but there was little evidence to support its effectiveness in LMIC.

At the community/organizational level, several interventions that applied a combination of approaches (e.g., informational, behavioral, and environmental) were found to be effective (Table 1). School- and workplace-based interventions, in particular, had the strongest and most consistent evidence for PA interventions combining several approaches for behavior change. For example, strong evidence for recommendation was found for school-based interventions that involved exercise groups, enhanced social support and self-esteem, active commuting campaigns, increased time spent in moderate/vigorous PA during physical education classes and decreased screen time, and the involvement of parents. These interventions were conducted in high- and low-and-middle-income countries and among culturally and socio-economically diverse populations. Workplace-based interventions with strong evidence for recommendation involved PA education, discounts to fitness centers, motivational sessions, supervised sessions, and policy support measures. These interventions were only studied in high-income countries (i.e., US, Australia, and New Zealand). Community-wide campaigns involving multiple approaches (social support, health education, etc.) and several community sectors were also found to be effective in high-income countries but there was insufficient evidence to evaluate its effectiveness in Latin America.

At the physical/policy environmental level, the following strategies showed sufficient to strong evidence for recommendation: point of decision prompts, creation of or enhanced access to places for PA combined with activities in informational outreach, community-scale urban design and land-use policies and practices, and street scale urban design and land use policies and practices. With the exception of one intervention in Colombia, all the environmental interventions reviewed were conducted in high-income countries, pointing to a large gap in understanding of the effectiveness of such interventions in LMIC.

Several limitations of our review should also be mentioned. First, most strategies reviewed were evaluated in the short-to medium term pointing to the need for long-term assessments for greater understanding of sustained impacts of these interventions. It is also important to note that most of the evaluated interventions were conducted in high-income countries, thus recommendations reported here may not be generalizable to other contexts. Nevertheless, our review shows that there is emerging evidence from countries in Latin America that have experienced the triple transition and are now focusing public health efforts and research on increasing PA.²¹ In addition, our findings are consistent with those described in the review in The Lancet on evidence-based PA interventions from around the world¹² and a review by the Cochrane Collaboration synthesizing systematic reviews and meta-analyses of randomized controlled trials for increasing PA levels³⁹. Using the socio-ecological framework to conceptualize PA interventions, we show that PA can be targeted at multiple levels of influence and by multiple sectors outside the health system (e.g., education, workplace, and urban planning) in various countries. Most of the impact on PA will come from sectors outside of health. Much more research is needed to better understand how to scale up evidence-based interventions, especially in the complex reality of LMIC. However, several countries have been reasonably effective at taking PA promotion to a national scale. In the following section, using brief case studies, we will describe how this occurred in Canada, Finland, Brazil, and Colombia. These descriptions point not only to the “what” (e.g., evidence of effective intervention approaches) of PA promotion but the “how” (e.g., mobilizing action, political will) of achieving change on a large-scale.

COUNTRY CASE STUDIES

Canada

Canada developed an early policy focus on PA, starting with the Fitness and Amateur Sport Act in 1961. A decade later, the national PA focused program ParticipACTION was launched.⁴⁰ This initiative was initially a public-private partnership, with subsequent Government engagement. It provided a consistent health communication around PA for four decades, and created a clear ParticipACTION ‘brand.’ This program achieved very high population rates (70–85%) of message recall, understanding, and credibility among adult Canadians.⁴⁰ ParticipACTION developed many national and regional worksite programs and youth sport and activity programs, and conducted serial mass media campaigns encouraging PA, sport participation, and ‘active living’. Canada had introduced the concept of lifestyle-related ‘active living’ in 1986, years ahead of most other developed nations. ParticipACTION became so associated with PA in Canada that it was the most commonly attributed source of the first Canadian PA Guidelines in 2002, even though ParticipACTION had not developed the guidelines, and the initiative was in abeyance between 2001 and 2005.⁴⁰ Although de-funded by Health Canada in 2001, ParticipACTION was revived in 2005, and developed a strong social marketing approach to promoting children’s physical activity.⁴¹ Unfortunately, in July 2014, ParticipACTION underwent a large funding cut from the Federal Government, with the recommendation that it should return to its private sector funding roots, with support from the Provincial governments.

In the period from the 1970s until around 1990, there were several national policy initiatives in Canada, with a good understanding of the cross-sectorial nature of PA action, usually involving partnerships between the health, sport and recreation sectors. In addition, the complex nature of Federal, Provincial, municipal and non-government sector responsibilities for PA was often beneficial. For example, when the national government effort was quiescent, other agencies or levels of government would implement effective PA strategies. Funding for PA was at its peak in the mid 1980s⁴², the period during which PA rates increased in Canada⁴³.

Since 2000, due to fiscal restraint and changes in government policy, there was less funding devoted specifically to PA. There were developments from 2005 through the Pan-Canadian Healthy Living Strategy, advocacy co-ordination through the Coalition for Active Living, ongoing and diverse PA programs in the Provinces,⁴² and possibly implementation of an ineffective children’s fitness tax credit scheme⁴⁴. Nonetheless, this devolution of implemented PA work resulted in a plateau of, and then slight decline in population PA levels in children and adults.⁴² The current partnership around the Active Canada 20/20⁴⁵ strategy (http://www.activecanada2020.ca/) has been developed to address this, but needs to obtain sustainable funding and Government support.

A key strength throughout this period was an ongoing PA monitoring system, through the Canadian Fitness and Lifestyle Research Institute⁴⁶; this measured not only PA levels, but also policies at the school, workplace, and municipality levels, as well as the built environment (http://www.cflri.ca/). Such long-term monitoring systems were useful in identifying the successful population-level increases in PA in Canada from around 1980 to 2000,⁴³ and subsequent lack of improvements thereafter.

Finland

Experience in Finland provides an interesting contrast to that from Canada. Leisure time PA levels in both countries increased over a period of 20 or more years and this appears to be the result of favorable public policies and consistent investment in infrastructure and programs.^47,48 In addition, both countries have had ongoing surveillance of PA, thus allowing an assessment of trends in population levels of PA. In Finland, as in Canada, public policy has provided a strong and stable base for developing national and community PA programs. However, the nature of the programs in Canada and Finland has been quite different. Finland developed a series of national policy statements on the importance of PA for health between 1970 and 2002 in the education, sport, transport, and health sectors.⁴⁷ Three sequential national PA initiatives followed from 1991 to 2005 with flexible funding for community programs as a key element. The emphasis of these initiatives was on building an infrastructure of parks, trails, sports and recreational facilities, and community centers coupled with funds for local programming driven by grass roots community engagement. There has been relatively little emphasis in Finland on mass media to promote PA, perhaps in part because of the already strong social value of sport and PA.⁴⁷ As of 2004 Finland had more than 30,000 sites for sports and recreation (one for every 176 citizens). More than 90% of Finns report using the extensive network of paths and trails for either recreation or transport. Several surveys show increases in leisure time PA (LTPA) among Finnish adult men and women between the 1970s and 1980s and 2000.^47,48 The proportion of both men and women reporting regular PA increased from approximately 40% to 60%.⁴⁷ In East Karelia a series of six surveys between 1972 and 1997 showed declining sedentary time and increasing LTPA for both men and women.⁴⁸ It appears that LTPA has plateaued for Finish adults since about 2000 while occupational and transport activity continue to gradually decline. In summary, Finland has been able to substantially increase LTPA over a period of decades through strong multisectoral public policy, consistent investment in community infrastructure and programs, and attention to local needs and culture. It is interesting to note that even with near optimal public policy, infrastructure, and programming only a bit more than half of the adult population is regularly physical active during leisure time.

Brazil

Health has been a constitutional right in Brazil since 1988.⁴⁹ Following that legal landmark a unified public health system was created, providing access to health care for the entire population, and with an explicit focus on health promotion.^7,49 In the late 1990’s a new PA promotion model was initiated in Brazil: Academia da Cidade, a community intervention that started in the city of Recife, a state capital in the Northeast of Brazil. Academia da Cidade is characterized by free daily PA classes in early mornings and late afternoons led by trained physical educators. An important environmental component of the program is the re-engineering of public parks or plazas, often in poor and dangerous neighborhoods. This creates safe public space for PA with good equipment and supervision. A close connection with the public primary health care system is integral to Academia da Cidade, allowing for easy referrals for prevention and treatment of NCD.

Academia da Cidade in the city of Recife has been evaluated with a combination of quantitative and qualitative research studies. A population-based phone survey showed that both current and former participants were more likely to be active than community members who had never participated in the program.⁵⁰ Less direct sources of exposure, such as having heard about the intervention or having seen classes, were also associated with higher levels of PA.⁵⁰ A study using direct observation showed that individuals using public spaces with Academia da Cidade units were more active than those visiting similar locations without the program.⁵¹ Other studies indicated a high-level of satisfaction of both users and instructors with the intervention.⁵²

A key limitation of most existing PA interventions worldwide is that few have been scaled-up to national or state level. This is not the case for Academia da Cidade. Several cities in Brazil adapted the model based on its popularity and success. Based on the careful evaluation of the program in Recife and public demand, the state government of Pernambuco decided to expand the program to all 185 municipalities in the state.⁵¹ Preliminary findings suggest that the magnitude of the increase in PA is even greater than was observed in single-city studies. Academia da Cidade has also been exported and adapted for Latino communities in the US.⁵³

However, the most promising development has been a massive national expansion of the Academia da Cidade program.⁵⁴ The Federal Government has funded over 2,000 cities in Brazil to deliver Academia da Cidade (now named Academia da Saúde – Healthy Gym) to the population. To date, more than 400 cities have built the program infrastructure and are delivering community PA classes.

Colombia

The National Constitution of 1991 established sports and recreation as a right for all Co-lombians. Funding and promotion for sports and recreation were also defined as responsibilities of the state.⁵⁵ However, Colombia’s emphasis on PA as a public health issue is relatively new. A number of city programs began in the 1990s, spawning a national physical activity network by 2002. An intersectoral government commission for PA was created in 2008, and in 2009 the Co-lombian congress passed a national obesity law⁵⁶ that included strategies for improving environments, policies, and programs for PA. The National Development Plan 2010–2014 included PA promotion as a priority, with specific ten-year plans for sports, recreation, physical education, and public health.⁹ Stimulated by both supportive policies and local programs the national sports institute (Coldeportes) launched a national PA program in 2003 and expanded it to healthy lifestyles in 2011.⁵⁷ The national program focuses on training public health and PA professionals from each of the 32 departments in Colombia to deliver community-based programs modeled on successful municipal programs such as Por su Salud Muévase Pues in Medellín, Risaralda Activa, and Muévete Bogota, and the ciclovías of Bogotá, Medellin, and Cali (open streets programs).^58–60 Free PA classes in public parks, plazas, and community centers similar to those in Brazil, and a network of 67 open streets programs (Vías Activas y Saludables) are key components of the national program. Evaluation of the Ciclovía and Recreovia (community classes) programs conducted as part of international partnerships suggest that these programs are effective at increasing the proportion of the population meeting PA recommendations and are also cost beneficial.^61,62 National nutrition and health surveys conducted in 2005 and 2010 showed an increase in overall PA among adults in Colombia from 50.1% to 53.5%. In contrast to data from high-income countries, walking for transport increased (24.2% to 33.8%), biking for transport was unchanged (6.4% to 5.6%), and the prevalence of PA in leisure time decreased (24.3% to 19.9%).⁶³ Colombia demonstrates the feasibility of implementing a national PA promotion program in a LMIC, but it is not yet clear whether the increases in PA prevalence are a result of public health, sport, and recreation programs or changes in the urban environment and public transport.

CONCLUSIONS

In summary, we have made a case for PA promotion as a classic population health endeavor. Substantial evidence for effective interventions exists at the community level, and a handful of cases suggest that effective interventions can be scaled up to the national level. Based on these examples one may ask, what combination of planned public health interventions, partnerships, and actions in various sectors is most likely to result in population level increases in PA? There are a number of common characteristics that emerge from the evidence-based reviews and the experiences in Canada, Finland, Brazil, and Colombia. Large scale programs for PA promotion and NCD prevention appear to evolve much more from community need and political will with some guidance from the evaluation of pilot programs than from synthesis, adaptation, and implementation of research findings. A focus on action with good evaluation guiding further investment is evident in the cases of ParticipACTION in Canada, the North Karelia Project in Finland, community PA classes in Brazil, and the ciclovía in Colombia. In order to deliver a sufficient dose of intervention to change behavior it seems that the balance must skew towards action and reach. When research is the primary goal of community projects, evaluation may become so much the priority that it consumes the resources required to deliver sufficient intervention. Nevertheless, solid evaluation is also essential. We know that the programs in Canada, Fin-land, Brazil, and Colombia were effective because in all cases there was a combination of targeted evaluation and continuous national surveillance systems that included consistent measures of PA allowing for an assessment of change over time. It is also worth noting that some aspects in the scaling-up of these four country cases differ markedly. While Brazil and Colombia built their national programs around scaling up well-evaluated large city programs, Finland s success seems more a matter of high cultural value of PA and a steady flow of supportive programs and initiatives. Canada used sustained mass media promotion of PA in a uniquely effective manner.

Despite the differences in approach, size and diversity of populations, geography, income, and culture, several other common factors emerge from the cases of these four countries. PA and sport are highly valued in the culture, for rich and poor, and generally for both genders. Evidence-based strategies for promoting PA were effectively adapted to the social norms, culture, and context of each country. Public space and public facilities also played key roles in each country. In Finland and Canada, community centers and robust systems of parks and trails created an excellent infrastructure for PA. In Brazil and Colombia, challenging, crowded, chaotic, often dangerous urban areas have led to a special emphasis on utilizing selected public streets, plazas, and parks to provide secure and attractive areas where people can congregate for PA and social activity. It is intriguing to note that the success stories for national PA promotion come from either countries with a high degree of social equity (Finland and Canada) or countries that are focused on PA as a strategy to explicitly address social inequity (Brazil and Colombia). The themes of public good and public space appear to be integral to successful large-scale PA promotion.

While PA as a public health discipline is still in the early stages of evolution, some recommendations may be reasonably drawn from research and global experience. Evidence-based interventions are necessary but not sufficient for large-scale public health efforts. Adaptation of these strategies to country, culture, and context is critical. An important part of this process will involve tailoring of strategies based on social norms related to PA and sport, realities of public space and infrastructure, and issues of equity and security. Favorable actions in sectors outside of public health and medicine (e.g., urban planning and transportation) are essential for large-scale PA promotion. Public investment in walkable city centers and public transport with attention to pedestrians and cyclists, parks, and public safety may be driven by concerns related to economic development, climate change, or urban quality of life, but will have major impacts on PA. An isolated public health strategy for PA is unlikely to be successful as many of the necessary actions occur in sectors other than public health and because sustained funding is nearly impossible without the broader political support associated with strong partners and constituencies. High-quality, ongoing PA surveillance is also essential as it is impossible to judge success at the national level without it. Increasing PA globally will depend primarily on successfully applying these lessons in LMIC that account for approximately 90% of the world population. The experience of the last decade in Latin America suggests that this is feasible, but the situation may differ substantially in Asia, Africa, and the Middle East. It is likely that the concepts we have summarized will hold, but how they are operationalized may differ. Safety from crime and traffic, congested unplanned urban conglomerations, climate, and less social desirability of sport and PA are likely to be especially challenging in these regions. Research on determinants, correlates, and intervention effects specific to countries in Asia, Africa, and the Middle East is needed to guide public health strategies for PA. However, as we have seen in Canada, Finland, Brazil, and Co-lombia, the real key to population level impact may be government commitment and implementation of major new programs accompanied by selective, focused, high quality evaluation.

ABBREVIATIONS

LTPA

Leisure time physical activity

LMIC

Low and middle-income countries

NCD

Non-Communicable Diseases

PA

Physical activity

SEM

Socio-ecological model

US

United States