Actions for Increasing Physical Activity
Research shows that a sedentary lifestyle is a predictor of overweight and obesity (Must and Tybor, 2005). Physical activity is critical not only for optimal weight, but also for physical and cognitive development in childhood. Current recommendations are for children to engage in physical activity at least 60 minutes per day (HHS and USDA, 2008); this includes any physical activity accumulated throughout the day, such as playing, walking to school, and exercise. However, many children are not that active. A 2002 Centers for Disease Control and Prevention (CDC) survey found that 61.5 percent of children aged 9–13 did not participate in any organized physical activity during their nonschool hours and that 22.6 percent did not engage in any free-time physical activity (CDC, 2003). These findings reflect marked increases during the past several decades in sedentary activities of daily living among both children and adults (Brownson et al., 2005). This more sedentary lifestyle is the result of increased reliance on technology and labor-saving devices, such as use of automobiles rather than walking or biking, attributable in part to community designs that favor this mode of transport; use of washing machines and dishwashers in the household; less physical activity in the workplace because of computers and automated equipment; increased use of television and computers for entertainment and leisure activities; and use of elevators and escalators rather than stairs. In addition, increased concern about crime has reduced the likelihood of outdoor playing; and decreased walking and bicycling and increased driving in response to community design that favors cars (Goran and Treuth, 2001). These activities reduce the need for daily physical activity or make it more difficult to be physically active.
CREATING A HEALTHY ENVIRONMENT FOR PHYSICAL ACTIVITY
Aspects of what researchers and planners call the “built environment” are important determinants of physical activity for both children and adults and therefore of rates of childhood obesity (Black and Macinko, 2008; Booth et al., 2005). The built environment encompasses all of the man-made elements of the physical environment, including buildings, infrastructure, and other physical elements created or modified by people (e.g., sidewalks, streets, trails, bicycle lanes, parks, playgrounds), as well as the functional use, arrangement in space, and aesthetic qualities of these elements (e.g., zoning, neighborhood design, mixed-use development) (IOM, 2005). Handy (2005) categorizes these elements as follows:
Land use—the location and intensity of activities, including residential, commercial, and institutional activities, and the design and arrangement of the buildings and sites that house them.
Transportation systems—the physical layout and design of roads, sidewalks, bike paths, and other transportation infrastructure, and their function and appearance.
The “social environment” is just as important to physical activity. It includes such elements as family, friends, place of employment, home, culture, socioeconomic status, and neighborhood. The social environment also encompasses neighborhood reputation, defined by perceived safety and social nuisances, as well as social support and social capital (Black and Macinko, 2008). For example, parental modeling of and support for participation in physical activity (e.g., by providing transportation and purchasing equipment) has been associated with higher levels of physical activity in children (Hoefer et al., 2001; Sallis et al., 2000).
However, the environment in which some children live often makes it difficult to engage in physical activity. Many neighborhoods lack open space, parks, recreational facilities, or sports fields. Neighborhood features that encourage physical activity are consistently associated with decreased weight. Among these factors, mixed land use, access to fitness facilities, and neighborhood “walkability” have all been linked to higher levels of physical activity and lower body weight (Black and Macinko, 2008). These are all aspects of the built environment.
The built environment’s influence on childhood obesity is determined by its effect on physical activity levels and also, as the previous chapter explains, its effect on healthy eating. It can promote or deter physical activity, such as organized active recreation, active commuting, and unstructured play. Various elements
of the built environment affect different types of physical activity in a number of ways. For example, the distance from home to school or to the soccer field is a key factor in whether children walk or bicycle to these places rather than being driven (Handy and Tal, 2008; Kerr et al., 2006; McDonald, 2007). Safety along the route, whether from traffic or “stranger danger,” is also important (Carver et al., 2008; Davison and Lawson, 2006). The design of neighborhoods influences outdoor play outside of the school day. Access to parks and other safe places to play, for example, is associated with more frequent outdoor play (Davison and Lawson, 2006; Mota et al., 2005). If there are safe and appealing opportunities to walk, bicycle, play, or otherwise move outdoors, thus creating an environment that promotes physical activity, children are likely to engage in more physical activity.
DISPARITIES IN THE BUILT AND SOCIAL ENVIRONMENTS
A number of the elements that constitute beneficial built and social environments—such as good sidewalks, low-speed streets, attractive greenspaces, nearby trails, easily accessible recreation centers, people visible walking or playing outdoors, and low crime rates—often are characteristic of communities with higher socioeconomic status (SES). Lower-SES communities often must deal with the negative aspects of the environment, such as busy through streets, poor-quality bicycle and pedestrian infrastructure, dilapidated parks and playgrounds, and crime, that deter physical activity (Black and Macinko, 2008; Booth et al., 2005). In addition to low SES, a high concentration of minority populations is a predictor for such disparities. Neighborhoods with large Hispanic and African American populations, for example, are less likely to have public parks and private recreation facilities (Gordon-Larsen et al., 2006). Lack of availability of facilities that enable and promote physical activity may, in part, explain the lower levels of activity observed among low-SES and minority communities (Powell et al., 2006), as may hazardous conditions such as crime (Seefeldt et al., 2002). Therefore, as discussed in Chapter 3, local governments should make low-SES and minority neighborhoods a priority when implementing the action steps outlined in this chapter to address disparities in the built and social environments.
THE ROLE OF LOCAL GOVERNMENTS IN PROMOTING PHYSICAL ACTIVITY
Local governments have an important role to play in supporting and promoting physical activity, in large part through their influence on the built environment, but through other means as well. Local governments, particularly cities, have
significant power over the form of the built environment (Handy and Clifton, 2007). Through general plans and zoning codes, cities and other local government entities make decisions on land use policies and plan and design street layouts and locations, including requirements for sidewalks and allowable street widths. They also own and maintain neighborhood parks and playgrounds, and in many cases operate and maintain other recreational facilities. They can set requirements for developers to provide sidewalks, walking and biking trails, and greenspace in new developments, as well as invest public money in enhance existing areas. Through these actions, local governments create—or restrict—opportunities for physical activity for children.
Local governments can support physical activity in other ways as well. Parks and recreation departments, for example, often run sports leagues or offer dance, gymnastics, or other active classes. Many cities have worked with school districts to promote walking and bicycling to school through Safe Routes to School programs and related initiatives. More general efforts to improve traffic safety and enforce traffic laws make streets safer for children to walk, bicycle, and play. Such programs help ensure that children take advantage of opportunities afforded by the built environment and compensate for its deficiencies. Furthermore, local governments can provide support and resources to local organizations that want to create healthy environments.
The physical activity strategies and actions recommended by the committee for consideration by local governments are organized around three goals:
Encourage physical activity.
Decrease sedentary behavior.
Raise awareness about the importance of increasing physical activity.
For each goal, several strategies and action steps are provided, as well as examples of how some communities have implemented these actions. This list of goals and the strategies and action steps discussed under each are not prioritized, but, as stated in the introduction, certain action steps are bolded as being most promising. Local community leaders, members, and policy makers will be in the best position to decide which strategies and action steps will be most feasible and appropriate for the needs and circumstances of their community. The decision will be based largely on such factors as resources, priorities, leadership, and demographics. Following are the goals, strategies, and action steps related to physical activity.
ENCOURAGE PHYSICAL ACTIVITY
Encourage walking and bicycling for transportation and recreation through improvements in the built environment.
Walking and bicycling, whether for transportation or recreation, are important sources of physical activity for children as well as adults. Walking, in particular, has been described by health researchers as near perfect exercise (Lee and Buchner, 2008). The built environment has a significant effect on walking and bicycling. Deficiencies in walking and bicycling infrastructure and streets designed for vehicles create barriers to walking and bicycling. Community residents are less likely to walk or bicycle for transportation or recreation if streets do not include sidewalks and safe crossings (Badland and Schofield, 2005; Davison and Lawson, 2006; Saelens et al., 2003). Residents of lower-income neighborhoods are more likely to face challenges posed by streets and sidewalks in disrepair, missing or blocked sidewalks and poorly marked crossings. Excessively wide streets encourage speeding, thereby increasing risks to pedestrians and bicyclists. Traffic volume and speed are negatively associated with children’s participation in physical activity (Davison and Lawson, 2006). Many rural roads, where speed limits are high, lack shoulders that can accommodate a pedestrian or cyclist. Land use patterns also deter walking and bicycling. Community residents are less likely to walk or bicycle for transportation if distances to destinations such as schools, recreation, and shopping are far (Saelens and Handy, 2008).
Improvements to these elements of the built environment can encourage walking and bicycling. Research shows that older, traditional neighborhoods with a mix of uses and well-connected street networks support physical activity as residents walk or ride their bicycle to nearby destinations (Badland and Schofield, 2005; Frank et al., 2004). Building and maintaining sidewalks and safe street crossings appears to hold some promise in promoting physical activity in neighborhoods (Lee and Moudon, 2008). Sidewalks may even affect obesity (Booth et al., 2005). Infrastructure improvements in the vicinity of schools can increase the number of children who walk and bicycle (Boarnet et al., 2005). Less experienced pedestrians and bicyclists may feel more comfortable on trails and paths separated from vehicle
traffic. Community-scale and street-scale urban design and land use policies and practices; proximity of residential areas to stores, jobs, schools and recreation areas; continuity and connectivity of sidewalks and streets; and aesthetic and safety aspects of the physical environment can all have an effect on physical activity rates (CDC, 2006b). Local governments can make these improvements through many different actions, some applied to new development and some to retrofitting existing areas, as noted in the boxes below. While a comprehensive approach is most effective, it’s important to note that simple changes, even a new coat of paint on a crosswalk, can have an impact on physical activity in a community.
Adopt a pedestrian and bicycle master plan to develop a long-term vision for walking and bicycling in the community and guide implementation.
Plan, build, and maintain a network of sidewalks and street crossings that creates a safe and comfortable walking environment and that connects to schools, parks, and other destinations.
Ways in Which Some Local Governments Have Implemented This Action Step
Plan, build, and retrofit streets so as to reduce vehicle speeds, accommodate bicyclists, and improve the walking environment.
Ways in Which Some Local Governments Have Implemented This Action Step
Plan, build, and maintain a well-connected network of off-street trails and paths for pedestrians and bicyclists.
Ways in Which Some Local Governments Have Implemented This Action Step
Increase destinations within walking and bicycling distance.
Ways in Which Some Local Governments Have Implemented This Action Step
Collaborate with school districts and developers to build new schools in locations central to residential areas and away from heavily trafficked roads.
Programs for Walking and Biking
Promote programs that support walking and bicycling for transportation and recreation.
Local governments can encourage residents to be more physically active by establishing programs that increase safety, provide education, and otherwise facilitate walking and bicycling. Perceived safety has a significant effect on walking for both children and adults (Carver et al., 2008; Cleland et al., 2008; Weir et al., 2006). Crime has an effect on physical activity as well (Ferreira et al., 2007; Gordon-Larsen et al., 2000). Providing children with a safe environment in which they can walk or bicycle to school can increase physical activity. Children who walk or bicycle to school have higher daily levels of physical activity and better cardiovascular fitness than do children who do not actively commute to school (Davison et al., 2008). Riding a bicycle at least two or more days during the week is associ-
ated with a decreased likelihood of being overweight during childhood (Dudas and Crocetti, 2008). Access to bicycles and safety equipment are necessary precursors to safe bicycling. Transit users have higher levels of physical activity owing to walking to transit stops (Zheng, 2008). Programs that support walking and bicycling often require partnerships with other organizations or agencies.
Adopt community policing strategies that improve safety and security of streets, especially in higher crime neighborhoods.*
Collaborate with schools to develop and implement a Safe Routes to School program to increase the number of children safely walking and bicycling to schools.
Improve access to bicycles, helmets, and related equipment for lower-income families, for example, through subsidies or repair programs.
Promote increased transit use through reduced fares for children, families, and students, and improved service to schools, parks, recreation centers, and other family destinations.
Implement a traffic enforcement program to improve safety for pedestrians and bicyclists.
Recreational Physical Activity
Promote other forms of recreational physical activity.
Recreational activities such as playing on a playground or shooting hoops are an important source of physical activity for children. Children who spend more time outdoors have higher levels of physical activity (Sallis et al., 2000). Access to neighborhood parks may increase levels of physical activity and reduce time spent in sedentary behaviors at home (Floriani and Kennedy, 2008; Kaczynskl and Henderson, 2008). Children are less likely to engage in recreational physical activity if parks or playgrounds are unavailable, in disrepair, or are not accessible by safe routes (Grow et al., 2008; Kaczynskyl and Henderson, 2008). This is especially true in higher-density lower-income neighborhoods that were built before
the establishment of park acreage requirements, where more residents are living in closer proximity to one another, and where public budgets may be insufficient to cover maintenance needs (Day, 2006). Participation in athletic activities is another way for children to increase physical activity and possibly lower body weight (Bélanger et al., 2009; Elkins et al., 2004; Weintraub et al., 2008), as is increasing access to recreation facilities (Baker et al., 2008; Sallis and Glanz, 2009).
Build and maintain parks and playgrounds that are safe and attractive for playing, and in close proximity to residential areas.
Ways in Which Some Local Governments Have Implemented This Action Step
Adopt community policing strategies that improve safety and security for park use, especially in higher crime neighborhoods.*
Improve access to public and private recreational facilities in communities with limited recreational options through reduced costs, increased operating hours, and development of culturally appropriate activities.
Create after-school activity programs, e.g., dance classes, city-sponsored sports, supervised play, and other publicly or privately supported active recreation.
Collaborate with school districts and other organizations to establish joint use of facilities agreements allowing playing fields, playgrounds, and recreation centers to be used by community residents when schools are closed; if necessary, adopt regulatory and legislative policies to address liability issues that might block implementation.
Create and promote youth athletic leagues and increase access to fields, with special emphasis on income and gender equity.
Build and provide incentives to build recreation centers in neighborhoods.
Routine Physical Activity
Promote policies that build physical activity into daily routines.
Building physical activity into daily routines makes physical activity automatic by making the active choice the default choice (Yancey, 2007). This is especially important because individuals most in need of increased physical activity are the least likely to choose to engage in physical activity. Approaches such as point-of-decision prompts to encourage use of stairs can increase physical activity in places frequented by children (CDC, 2006b). Changes in institutional practices and the built environment that structurally integrate physical activity into routines can increase automatic physical activity and are critical for widespread activity-promoting social norm change (Bower et al., 2008; Donnelly et al., 2009; IOM, 2006; Lara et al., 2008).
Institute regulatory policies mandating minimum play space, physical equipment, and duration of play in preschool, after-school, and child care programs.
Develop worksite policies and practices that build physical activity into routines (for example, exercise breaks at a certain time of day and in meetings or walking meetings). Target worksites with high percentages of youth employees and government-run and -regulated worksites.
Create incentives for remote parking and drop-off zones and/or disincentives for nearby parking and drop-off zones at schools, public facilities, shopping malls, and other destinations.
Improve stairway access and appeal, especially in places frequented by children.
DECREASE SEDENTARY BEHAVIOR
Promote policies that reduce sedentary screen time.
Every day, 8- to 18-year-olds spend an average of four hours watching TV, videos, DVDs, and prerecorded shows; just over one hour on the computer; and about 50 minutes playing video games (Roberts et al., 2005). Research shows that reducing screen time reduces the likelihood of being overweight (Jackson et al., 2009). According the American Academy of Pediatrics, children should limit total screen time to 2 hours or less per day (Bar-On et al., 2001). Children that meet this recommendation and meet physical activity recommendations are least likely to be overweight (Laurson et al., 2008). Behavioral interventions to reduce screen time can have a positive effect on obesity (CDC, 2006a).
Adopt regulatory policies limiting screen time in preschool and after-school programs.
RAISE AWARENESS ABOUT THE IMPORTANCE OF INCREASING PHYSICAL ACTIVITY
Media and Social Marketing
Develop a social marketing campaign that emphasizes the multiple benefits for children and families of sustained physical activity.
Media can be a key element to increase awareness and motivation and can be used to promote physical activity, decrease sedentary activity and to raise awareness of weight as a health issue. Evidence suggests that community-wide campaigns to increase physical activity can be effective (CDC, 2006b). High-frequency television and radio advertising, as well as signage may stimulate improvements in attitudes toward walking behavior (Beaudoin et al., 2007). The national VERB campaign is an example of a social marketing campaign that positively influenced physical activity in children. After 2 years, children in communities that received a high dose of VERB campaign advertising and promotional activities reported higher awareness and understanding of VERB, greater self-efficacy, more sessions of physical activity per week, and were more active on the day before being surveyed than children who received the average national dose (Berkowitz et al., 2008). Depending on the resources available, and the purpose of the campaign, both local development of campaigns and the adoption of national message campaigns may be useful. In keeping with the focus on changes that local governments can make to improve the food and physical activity environments of children, it is important to point out that media and social marketing campaigns can improve these environments by focusing on the reasons for improving children’s food and physical activity environments; and engaging the public in taking advantage of new resources in their environment such as recreation centers, playgrounds, walking paths, etc.
Develop media campaigns, utilizing multiple channels (print, radio, Internet, television, other promotional materials) to promote physical activity using consistent messages.
Design a media campaign that establishes physical activity as a health equity issue and reframes obesity as a consequence of environmental inequities and not just the result of poor personal choices.
Develop counter-advertising media approaches against sedentary activity to reach youth as has been done in the tobacco and alcohol prevention fields.
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