Articles throughout this special issue have highlighted decades of physical activity research and the substantial contributions it has made on improving our understanding of its relationship to both physical and mental health. Yet despite our current and growing understanding of the vital importance of physical activity, most of the population, including children, do not meet physical activity guidelines (1). Over the past three decades, many social, technological, occupational, and environmental advances have fundamentally shifted the way we live, work, and play. Although these advances have addressed and solved many problems, they simultaneously intensified the problem of physical inactivity. With so many modern touch-of-the-button conveniences, we have engineered physical activity out of everyday living. Therefore, perhaps the most extraordinary public health challenge of our time is how to make physical activity an easy choice, especially in environments where members of the population spend their greatest proportions of time—homes, communities, workplaces, and schools.
We have spent our careers addressing the challenge of increasing children’s accrual of moderate to vigorous physical activity (MVPA) in school environments. Collectively, we have published well over 300 articles on school-related physical activity with most aimed at improving children’s MVPA in physical education (PE), at recess, and through before, during, and after school programs. A significant proportion of our recent work has focused on school physical activity policy—the topic of this article. In this article, we provide background on school physical activity policy and its appeal for addressing physical inactivity. In addition, we present general research approaches and findings and outline our perspectives on future research needs. We begin by providing an overview of the school physical activity environment, distinguishing policies from practices, and outlining why school physical activity policy is widely viewed as a viable solution to improving population-level physical activity and health. Next, we describe relevant aspects of policy and provide an overview of related research aims and findings. Lastly, we provide our perspectives on research approach needs, and we make the case for more calculated research efforts to support evidence-based advocacy.
ELEMENTARY SCHOOL PHYSICAL ACTIVITY ENVIRONMENT
Regular physical activity engagement is important for children’s growth, development, and health. The revised 2018 National Physical Activity Guidelines recommend that children engage in MVPA for at least 60 min daily (2). Most do not meet guidelines, and some are at increased health risk—girls and children with disabilities, living in unsafe neighborhoods, and/or being part of an ethnic minority group (3,4). From a public health perspective, there has never been a greater need for schools to provide and promote physical activity, especially because they reach all children, regardless of race/ethnicity, disability, and socioeconomic status. Further, more than 35 million children attend elementary schools for approximately 175 d·yr−1, making it an ideal setting not only for providing and promoting physical activity but also for increasing and sustaining it at the population level (5).
PE and recess provide opportunities for children to be physically active. They are institutionalized as part of the school day in most elementary school settings. As well, recent efforts have been made to expand school physical activity opportunities to include classroom activity breaks, before and after school programs, and active transport (walking/biking) to and from school. Meanwhile, the federal reauthorization of the Elementary and Secondary Education Act of 2001, known as “No Child Left Behind,” has led to reductions in physical activity programs and resources (6), and today, fewer than 3% of elementary schoolchildren receive physical education every day (7,8).
SCHOOL PHYSICAL ACTIVITY POLICIES AND PRACTICES
Lack of progress in improving school physical activity programs has motivated interest in school physical activity policy. From an ecological perspective, policies change the guiding principles and procedural structures that relate to target behaviors (9) and therefore, in the school environment, have the potential to shape the function (e.g., aims, scope, and expected outcomes) and structure (e.g., how much, how often, and delivery personnel) of programs. For interventionists, policies hold wide appeal because once they are established, they remain part of the environment and affect target behaviors in a sustained manner.
School physical activity policies aim to change aspects of the prevalence and delivery of school physical activity program practices. Practices include not only the frequency and the duration of programs (e.g., PE, recess, before, during and after school programs, and classroom physical activity breaks) but also the aspects of the program content, how it is delivered, and by whom. Practices also relate to more indirect aspects of programs like staff training, program funding, and design, use, and maintenance of school facilities. Numerous studies of school-based physical activity have been conducted, and this research has identified multiple evidence-based school practices that more fully optimize children’s activity. This research has guided the development and promotion of school physical activity policy recommendations (10).
The relationship between policies, children’s access to physical activity programs (including program minutes), and children’s actual engagement in physical activity is complex, and research in this area is relatively new. Although there are some studies (11,12), including those examining the effects of state policies (13,14), research on school policy and its direct relationship to children’s physical activity is limited. In particular, there is little clarity on how specific policies contribute to children’s objectively measured physical activity in schools. Although there is a paucity of research with this focus, there are multiple factors that moderate the impact policy can have on children’s physical activity. For example, even when enacted, we know many schools do not fully comply with policies (15). Further, research has shown that school physical activity programs are commonly provided in ways that do not fully optimize the accrual of MVPA (16). Therefore, even when schools were in full compliance with a policy, the nature of the programs and their delivery may hamper children’s MVPA accrual. Thus, in addition to having a policy in place (policy enactment) and school adherence to the policy, it is imperative that the program be a quality one that incorporates evidence-based practices. Studying school policies and their direct effect on children’s physical activity is multifaceted and complex because of the nested nature of physical activity, practices, and policy and classes within schools, schools within districts, and districts within states. Figure 1 demonstrates this complexity by illustrating the different levels of policy (e.g., state, district, and school) and how policies at these levels may influence children’s physical activity directly or indirectly. These different levels of enactment, adoption, and implementation result in substantial variation at subsequent levels and in individual children’s physical activity—all of which have not been examined empirically.
Level of policy enactment, school compliance, and school practice are all important contextual aspects to consider when formulating physical activity policy research questions. Next, we describe these and other aspects of policy as essential considerations for school physical activity policy research efforts. For each area, we generally describe research approaches, findings, and gaps.
ASPECTS OF POLICY
Policy Enactment and Advocacy
Surveillance studies, particularly those conducted systematically over time, help to identify the prevalence of and changes in school physical activity policies and practices. For example, the School Health Policies and Practices Study is an effort undertaken by the Division of Adolescent School Health within the Centers for Disease Control and Prevention and assesses school health policies and practices that include school physical activity policies and practices at the state, district, school, and classroom levels. As well, the Society of Health and Physical Educators (SHAPE America) conducts periodic assessment of PE policies in U.S. schools. These studies show several school physical activity practice and policy gaps. As an illustration, consider these select findings from the 2016 School Health Policies and Practices Study and Shape of the Nation Reports:
- Although 19 states require elementary schools to meet minimum time requirements in PE, only Oregon and the District of Columbia meet the national recommendations for weekly time in PE at both elementary and middle school levels (17).
- Only 30.6% of districts require elementary schools to assess students’ fitness levels (17).
- Only eight states require elementary schools to provide daily recess (18).
- Only 15.4% of districts require each school to have a coordinator for school physical activity programs (17).
- Beyond PE and recess, only 1.7% of districts require elementary schools to provide regular classroom physical activity breaks during the school day (17).
- About 1/3 of school districts support or promote walking or biking to and from school (17).
Examining the prevalence of enacted school activity policies has been a stronger area of the research focus. Studies have examined state-codified laws and district-level policies. Findings from these studies generally indicate that few school physical activity policies exist at any level and that those in existence typically relate to PE. For example, the Classification of Laws Associated with School Students is a scoring system that evaluates codified state laws related to school PE and nutrition. Data from the Classification of Laws Associated with School Students show that nearly all states have at least one codified PE law but only 16 have codified recess laws (19). Another study reported 11 states had codified laws that generally addressed school physical activity minutes, but only one of these had a codified law for both PE and physical activity (20). In addition, the specified requirements in the laws generally fell short of professional recommendations or evidence-based practices. For example, only two states had laws requiring schools to provide the recommended number of weekly minutes (i.e., 150 min for elementary and 225 for secondary schools), and of the 16 states with recess laws, none required the recommended 30 min daily (19).
Research on how school policies are enacted is among the most critical of gaps in this line of investigation. Studies on policy enactment have been conducted generally (21), and in some specific areas (e.g., education (22), school violence (23), and obesity (24)), only a few have focused specifically on physical activity policy enactment (25). More efforts have targeted childhood obesity policy enactment, and school physical activity policy has been included in some of these (26–29). In general, the studies have examined associations between existing policy and demographical, sociological, and environmental characteristics with a typical goal of identifying predictors of policy enactment. Reviews summarizing this work have not been published and generalized predictors of school physical activity policy enactment have yet to be identified.
Advocacy, the act of promoting a cause, is a catalyst for policy enactment. Thus, we and others have called for research on advocacy (30,31). Related to school physical activity, the cause is change in physical activity–related practice(s). Advocacy that leads to policy enactment is rarely a single act but rather is a series of strategic actions over time that form a campaign. For federal- and state-level policy enactment, campaigns often extend over many years. To date, school physical activity policy advocacy campaigns have experienced unclear, unorganized, and unsustained efforts. Effective advocacy campaigns require understanding of two target groups—the policy-making body (policy maker) and others who can join the cause. As Figure 2 illustrates, there are a host of school physical activity policy makers at the state, district, school, and class levels. Meanwhile, there is a need for focused research efforts on understanding the most effective advocacy mechanisms and messaging for each of these policy makers.
Policy Language Associations
Policies are formalized in writing as laws, statutes, regulations, or policies found in formal organizational documents such as school policy or employee handbooks. For enacted policies, a fundamentally critical aspect is the policy language, especially the specificity and strength of the language. When the language is ambiguous and/or lacks specificity, it creates opportunity for “loopholes,” compromises the general policy aim (32), and ultimately limits the policy impact on children’s accrual of physical activity. For these reasons, the scope, specificity, and strength of written policy language are important research targets. To examine the strength of policy language, we and others have adapted the coding methods of The School Wellness Policy Evaluation Tool developed by the Robert Wood Johnson Foundation Healthy Eating Research Program. Research in this area has shown that school physical activity policies are weakly written and lack specificity (25,33–36).
Assessing the relationship between school physical activity policy language, physical activity practices, physical activity, and other health outcomes has been an important focus of research. Some researchers have examined associations between state policies, the strength of the language, and the reported time spent in PE, physical activity, and other outcomes like body mass index changes (11,37,38). Findings from these studies typically point to the promise and potential of codified laws that support PE. For example, one study (11) reported the odds of schools providing at least 150 min of PE per week and 20 min of recess per day were greater in states that had these policies. Another study found that elementary and middle schools in states with specific PE time requirements provided about 27 and 60 more PE minutes, respectively, than those in states without specific mandates (37). In a related study, girls from states with strong laws reported participating in physical activity and PE more frequently than those from states with no codified laws (38).
Although these findings are promising, at least one study reported finding only minimal associations between state policies and school practices (39). Nonetheless, some studies have shown that state and district policies, even when worded weakly, can have important implications for school practices (11,40). We found that district policies are associated with several evidence-based physical activity practices, yet few policies were associated with the number of minutes PE or recess offered (40). Other studies have examined outcome differences between schools in and out of policy compliance. For example, Sanchez-Vaznaugh and colleagues (41) found that students in school districts in compliance with the state PE time policies had greater odds of meeting the physical fitness standards than those in noncompliant districts.
Dissemination, Implementation, and Accountability
Dissemination, implementation, and accountability mechanisms designed to ensure compliance are also important aspects of school physical activity policy. Dissemination refers to how policies are distributed and communicated to administrators, teachers, staff, and other constituencies (e.g., parents and students) for the designed purpose of promoting awareness and implementation. From a research perspective, the importance of understanding how policies are disseminated is intuitive, yet few dissemination studies have been conducted (42). We believe that a well-designed dissemination of both new and existing school physical activity policies may be lacking. Specifically, dissemination may lack a cogent plan that includes clarification of who is responsible for it, when and how it should occur, and the available resources. We believe that typical dissemination practices are passive in nature (e.g., mass distributed hard copy documents, website posts, and e-mail notices) and assume, rather than verify, dissemination targets read and understood the policy.
The extent that school physical activity policies have the potential to change practices, and ultimately, children’s physical activity, depends on the degree to which they are implemented. For this reason, implementation is an essential part of school physical activity policy. Degree of implementation refers to the extent to which school practices reflect what is espoused within the policy language. Implementation likely depends on a host of factors and includes, but may not be limited to, the clarity and strength of the policy language (e.g., required vs recommended), the dissemination effectiveness, and the monitoring and accountability mechanisms in place.
Implementation studies are fewer but generally seek to identify policy implementation plans and determine the degree to which there is compliance with enacted policies. Most have found that policy implementation plans are lacking (43) and, if in place, are nonspecific beyond requiring schools to complete self-reports (20). Some researchers have called for the need to move beyond self-reports to monitor implementation more closely so that struggling schools can be supported in their efforts to comply with policies (44).
As we have highlighted, the complexities of school physical activity policies make assessing their dissemination and implementation especially challenging. As Figure 1 shows, school policies can be enacted at various levels, and as illustrated in Figure 2, within each level, multiple policy makers can enact policies. Studies that examine policy dissemination and implementation across levels (e.g., district policy enactment to school implementation) may help to identify critical opportunities for developing interventions that improve policy dissemination and implementation. In this regard, additional research is needed to identify specific dissemination actors and processes to improve understanding of school physical activity policy dissemination and effective methods for promoting implementation at all policy levels. As well, research is needed to grow our understanding of the associations between dissemination and implementation and other contextual factors such as community demographics, political aspects, and logistical and technical capacities. In addition, as current measures of implementation and accountability rely heavily on school self-reports, few studies have objectively examined their effects on implementation. Thus, growing understanding of accountability measures, especially feasible ones, is greatly needed.
Although school physical activity policy research is growing, it is still very limited. Much of what we have outlined reflects our perspectives on essential research considerations that will help provide an evidence base to guide policy efforts. In the last segment of this article, we summarize what we believe are other important future research needs.
FUTURE RESEARCH NEEDS
Most research on school policies use survey methods in which respondents complete online or mail-back questionnaires. Such methods are important because they are a relatively inexpensive way to generate a macro view of policies and practices within a large number of schools. Nonetheless, surveys are limited and imperfect because of potential recall error and social desirability bias. Response rates may also be low, with some schools declining to participate, especially if the results might cast them in a negative light (45). As well, respondents are often distal from the actual school site, such as those in state education or school district offices. Even when surveys are completed by individuals from the same school campus, the responses may differ depending on their status/position such as school principal or PE teacher (40).
Nonetheless, the use of surveys remains important for surveillance and monitoring school policy prevalence. On-site data collection (i.e., “ground-truthing”) using direct methods, however, is also needed to both authenticate responses and generate data that questionnaires and interviews are unable to provide (e.g., student physical activity during specific contexts such as PE and recess). These on-campus methods can include both examining policy-related documents and directly observing ongoing programs. For example, two studies in Texas used the systematic observation of PE classes to assess the implementation and effect of Texas Senate Bills 19 and 42 (13,14). Both studies reported that students engaged in MVPA for greater than 50% of lesson time, thereby exceeding the public health goal.
Making direct observations using validated instruments allows researchers to explore school policies at the micro level. Although numerous ways are available to assess physical activity (e.g., self-reports, accelerometers, pedometers, and heart rate monitoring), systematic observation methods have the advantage of appraising the current context of the location/program in which the activity occurs. This includes being able to directly and simultaneously generate information on physical activity and concurrent physical and social factors operating in the setting ( (46,47). Systematic observation has the advantage of low participant burden (e.g., no recall, wearing monitors, or providing fluid samples) and, as a direct method, has strong internal (or face) validity. In addition, observations can be done in environments where other measurement tactics do not function well, such as in aquatics and gymnastics. Nonetheless, direct observation requires observer training and gaining access to school locations, and there is a possibility of participant reactivity.
Many observation systems are available, but two of the most widely used for assessing physical activity and its contexts in elementary schools are System for Observing Fitness Instruction Time (SOFIT (48)) and System for Observing Play and Leisure in Youth (SOPLAY (49)). These companion tools use similar activity codes that have been validated using heart rate monitoring, accelerometers, and pedometers. Their protocols are free and accessible videos on YouTube enable observers to be trained and assessed in a consistent manner. Apps (iSOFIT and iSOPLAY) for using the tools with iPADS are also available free on iTunes, and these make data entry, storage, analysis, and file sharing easier.
The number of studies on school physical activity programs and on physical activity and sedentary behavior has increased over the last few decades. Findings from these studies have served as a foundation for the development of comprehensive school physical activity frameworks, including PE, recess, classroom physical activity breaks, other before–during–after school physical activity opportunities, and active transport to school programs. Today, there is an abundance of research that shows school physical activity programs can significantly contribute to children’s physical activity accrual. A large body of evidence illustrates the value of providing evidence-based PE program and providing daily recess (10,50). Studies consistently show that when an evidence-based PE program is implemented successfully, the likelihood of students engaging in MVPA for at least 50% of class time increases dramatically (51). As well, providing at least 20 min of recess per day is associated with improved classroom behavior, attention, and participation in health-enhancing physical activity (50). Research has also shown that (a) daily structured classroom physical activity breaks help students accumulate approximately 13% more MVPA minutes at school per week (52); (b) structured before, during, and after school physical activity programs that are led by trained staff members and focus on specific MVPA goals can increase children’s physical activity (53); and (c) children who walk/bike to and from school accrue more overall daily physical activity (54). This body of work has guided and will continue to guide the practice aims of school physical activity policies (e.g., policies requiring PE be delivered by certified PE teachers).
Although we have learned a great deal about the potential of school physical activity programs in the last 40 yr, it is important to acknowledge that evidence-based programs require resources, and in many cases, their costs may be prohibitive. Lawmakers are often eager to find ways to support prevention programs but may face extraordinary challenges in balancing budgets and prioritizing resources. Thus, advocacy is needed to persuade lawmakers that school physical activity programs are indeed a worthwhile investment.
Whenever possible, research evidence should be used to develop compelling advocacy messaging. Although there is extensive research evidence on school physical activity practice, there are considerable gaps here too. Hence, given the focus of the of Translational Journal of the American College of Sports Medicine, it is fitting to highlight the important need for a more deliberate conceptualization and design of school physical activity policy research for advocacy and translation to policy makers. Based on our experience, research is needed to illuminate creative measures on how to overcome known barriers to school physical activity (e.g., time and staffing) and the short-, intermediate-, and long-term health and financial benefits. Specifically, cost–benefit analyses of evidence-based school physical activity practices are needed. Lawmakers typically have specific questions about the costs associated with evidence-based recommendations (e.g., requiring certified PE teachers) and the economic and quality of life short- and long-term benefits. It is clear to us that research of this nature would go a long way in helping policy makers better weigh difficult priorities.
Our goal in writing this article was to provide an overview of school physical activity policy and clarify its potential and limitations for increasing children’s accrual of MVPA. To accomplish this, we described school physical activity policy research aims, approaches, and findings generally and then offered our views on critical research gaps. Lastly, we commented on the need for research to incorporate direct measures of the school environment and for studies that assess advocacy and translation to policy makers. Our hope in writing this article was to inspire greater understanding and interest in conducting school physical activity policy research.
This manuscript does not constitute endorsement by the American College of Sports Medicine.
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