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The Effectiveness of Interventionsto Increase Physical Activity

A Systematic Review

Emily B. Kahn, PhD, MPH, Leigh T. Ramsey, PhD, Ross C. Brownson, PhD, Gregory W. Heath, DHSc, MPH,Elizabeth H. Howze, ScD, Kenneth E. Powell, MD, MPH, Elaine J. Stone, PhD, MPH, Mummy W. Rajab, MS,Phaedra Corso, PhD, and the Task Force on Community Preventive Services

Overview: The Guide to Community Preventive Services methods for systematic reviews were used toevaluate the effectiveness of various approaches to increasing physical activity: informa-tional, behavioral and social, and environmental and policy approaches. Changes inphysical activity behavior and aerobic capacity were used to assess effectiveness. Twoinformational interventions (point-of-decision prompts to encourage stair use andcommunity-wide campaigns) were effective, as were three behavioral and social interven-tions (school-based physical education, social support in community settings, and individ-ually-adapted health behavior change) and one environmental and policy intervention

(creation of or enhanced access to places for physical activity combined with informationaloutreach activities). Additional information about applicability, other effects, and barriersto implementation are provided for these interventions. Evidence is insufficient to assess anumber of interventions: classroom-based health education focused on informationprovision, and family-based social support (because of inconsistent findings); mass mediacampaigns and college-based health education and physical education (because of aninsufficient number of studies); and classroom-based health education focused on reduc-ing television viewing and video game playing (because of insufficient evidence of anincrease in physical activity). These recommendations should serve the needs of research-ers, planners, and other public health decision makers.

Medical Subject Headings (MeSH): exercise, leisure activities, physical fitness, physicalendurance, decision making, evidence-based medicine, economics, preventive health services,public health practice, meta-analysis, review literature (Am J Prev Med 2002;22(4S):73107)

Introduction

Regular physical activity is associated with en-hanced health and reduced risk of all-causemortality.14 Beyond the effects on mortality,

physical activity has many health benefits, includingreduced risk of cardiovascular disease,5,6 ischemicstroke,79 noninsulin-dependent (type 2) diabe-tes,1016 colon cancers,1720 osteoporosis, 2123 depres-sion,2427 and fall-related injuries.2831 Despite the ben-efits of regular physical activity, only 25% of adults inthe United States report engaging in the recommendedamounts of physical activity (i.e., 30 minutes of moder-ate-intensity activity on 5 or more days per week, or 20minutes of vigorous-intensity activity on 3 or more days

per week)32; 29% report no leisure-time regular physi-cal activity33; and only 27% of students (grades 9through 12) engage in moderate-intensity physical ac-tivity (30 minutes, 5 or more days per week).32

In Healthy People 2010,32 physical activity is ranked asa leading health indicator. Healthy People 2010 hasdeveloped goals to improve levels of physical activityamong adults, adolescents, and children and to reducesedentary behavior among adolescents (Table 1).

Recommendations to increase physical activity havebeen made for individuals and clinical settings but notfor community settings. Increased physical activity has

From the Division of Prevention Research and Analytic Methods,Epidemiology Program Office (Kahn, Ramsey, Rajab, Corso), Divi-sion of Nutrition and Physical Activity, National Center for ChronicDisease Prevention and Health Promotion, Centers for DiseaseControl and Prevention (Heath), Atlanta, Georgia; the Task Force on

Community Preventive Services and St. Louis University, School ofPublic Health (Brownson), St. Louis, Missouri; Division of HealthEducation and Promotion, Agency for Toxic Substances and DiseaseRegistry (Howze), Atlanta, Georgia; Epidemiology and PreventionBranch, Georgia Department of Human Resources (Powell), Atlanta,Georgia; and National Heart, Lung, and Blood Institute, NationalInstitutes of Health (Stone), Bethesda, Maryland

Dr. Stone is currently affiliated with the Department of PhysicalPerformance and Development, University of New Mexico, Albuquer-que, New Mexico.

The names and affiliations of the Task Force members are listed inthe front of this supplement and at www.thecommunityguide.org.

Address correspondence and reprint requests to: Peter A. Briss,MD, Community Guide Branch, Centers for Disease Control andPrevention, 4770 Buford Highway, MS-K73, Atlanta, GA 30341.E-mail: [email protected].

73Am J Prev Med 2002;22(4S) 0749-3797/02/$see front matter


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been linked not only to behavioral and social correlatesbut also to physical and social environmental corre-lates. Therefore, the role of community-based interven-tions to promote physical activity has emerged as acritical piece of an overall strategy to increase physicalactivity behaviors among the people of the UnitedStates. In 1996, the American College of Sports Medi-cine and the Centers for Disease Control and Preven-

tion (CDC) recommended that every adult in theUnited States accumulate 30 minutes or more of mod-erate-intensity physical activity on most, preferably all,days of the week.34 That same year, the U.S. PreventiveServices Task Force recommended that healthcare pro-

viders counsel all patients on the importance of incor-porating physical activity into their daily routines.35 Todate, community-based interventions to increase phys-ical activity have not been summarized in an evidence-based process.

The Guide to Community Preventive Services

The systematic reviews in this report represent the workof the independent, nonfederal Task Force on Com-munity Preventive Services (the Task Force). The TaskForce is developing the Guide to Community PreventiveServices (the Community Guide) with the support of theU.S. Department of Health and Human Services(DHHS) in collaboration with public and private part-ners. The Centers for Disease Control and Prevention(CDC) provides staff support to the Task Force fordevelopment of the Community Guide. A special supple-ment to the American Journal of Preventive Medicine,

Introducing the Guide to Community Preventive Services:

Methods, First Recommendations, and Expert Com-mentary, published in January 2000, presents thebackground and the methods used in developing theCommunity Guide.36

Healthy People 2010 Goals and Objectives for

Increasing Physical Activity

The interventions reviewed in this article should beuseful in reaching the objectives set in Healthy People2010.32 The two main foci of the Healthy People preven-tion objectives are to increase (1) the amount ofmoderate or vigorous physical activity performed bypeople in all population subgroups and (2) opportuni-ties for physical activity through creating and enhanc-ing access to places and facilities where people can bephysically active. This article provides information oninterventions that relate to both of these foci, which canbe used by communities to help increase levels of

exercise and fitness. The specific objectives are listed inTable 1.

Recommendations from Other Advisory Groups

The U.S. Preventive Services Task Force

In 1996, in the Guide to Clinical Preventive Services,35 theU.S. Preventive Services Task Force (USPSTF) recom-mended that healthcare providers counsel their pa-tients to incorporate regular physical activity into theirdaily routines. This recommendation was based on theaccepted health benefits of such activity rather than the

proven effectiveness of clinician counseling. The

Table 1. Selected objectives for increasing physical activity (PA), Healthy People 201032

Percentage of population

Objective Population Baselinea 2010 objective

No leisure-time PA Adult 40% (1997) Reduce to 20%At least 30 minutes of moderate physical activity

regularly, preferably dailyAdult 15% (1997) Increase to 30%

At least 30 minutes of moderate physical activity

on

5 of previous 7 days

Adolescents 27% (1999) Increase to 35%

Vigorous PA that promotes the developmentand maintenance of cardiorespiratory fitness3 days per week for 20 minutes/occasion

Adult 23% (1997) Increase to 30%

Vigorous PA that promotes the developmentand maintenance of cardiorespiratory fitness3 days per week for 20 minutes/occasion

Adolescents 65% (1999) Increase to 85%

Daily school physical education Adolescents 29% (1999) Increase to 50%View television 2 hours on a school day Adolescents 57% (1999) Increase to 75%Trips of1 mile made by walking Adults 17% (1995) Increase to 25%Trips to school of1 mile made by walking Children and adolescents 31% (1995) Increase to 50%Trips of5 miles made by bicycling Adults 0.6% (1995) Increase to 2%Trips to school of2 miles made by bicycling Children and adolescents 2.4% (1995) Increase to 5%aYears indicate when the data were analyzed to establish baseline estimates. Some of the estimates are age adjusted to the year 2000 standard

population.Source: U.S. Department of Health and Human Services. Healthy people 2010: conference edition. Washington, DC: U.S. Department of Healthand Human Services, 2000.32


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USPSTF found that problems associated with establish-ing the effectiveness of counseling included lack ofinformation about long-term compliance and the typi-cal problems of generalizing to a broad population.The USPSTF is revisiting the effectiveness of clinicalinterventions for promoting long-term changes in phys-ical activity, and a revised recommendation will bereleased later this year.

American College of Sports Medicine/CDC

A panel of scientists convened by the American Collegeof Sports Medicine and CDC developed a consensusstatement recommending that every adult in theUnited States accumulate 30 minutes or more of mod-erate-intensity physical activity on most, preferably all,days of the week.34 This recommendation was modifiedto emphasize that physical activity does not need to becontinuous or strenuous to produce health benefits.

The Surgeon Generals Report37 and the NationalInstitutes of Health Consensus Statement38 support thisrecommendation.

Methods for Conducting the Review

The general methods used to conduct systematic re-views for the Community Guide have been described indetail elsewhere.39,40 The specific methods for conduct-ing this review, including intervention selection, out-come determination, and search strategy for interven-

tions to increase physical activity, are presented inAppendix A. The conceptual approach to the review,critical both for describing the methods and for under-standing the results of the review, is described below.

Conceptual Model

The general conceptual model (also called the logicframework) used to evaluate the effectiveness of inter-

ventions to increase physical activity is shown in Figure1. This framework illustrates the relationships between

physical activity, several indicators of physical fitness,and morbidity and mortality outcomes. For example, alarge body of literature shows that increasing physicalactivity results in physiologic improvements, affectingendurance, strength, body composition, insulin sensi-tivity, and lipid levels.37 In turn, these improvementshave been shown to result in improved health andquality of life across a variety of conditions. Those whoare physically active have a reduced risk of developingcardiovascular disease,4144 type 2 diabetes (formerlycalled noninsulin-dependent diabetes),1416 coloncancers,1720 osteoporosis,2123 and depression,2527

and of having fall-related injuries.2831

Selection of Interventions for Review

The relationships between increased physical activityand health were assumed by the coordination team tobe well established and, subsequently, were not thefocus of the systematic review. Instead, the coordina-tion team focused on interventions to increase physicalactivity behaviors. By using the categories of behavioral

precedents established in the logic framework, thecoordination team (defined in Appendix A, see authorlist) initially developed the following three categories ofinterventions:

Informational approaches to change knowledge andattitudes about the benefits of and opportunities forphysical activity within a community;

Behavioral and social approaches to teach people thebehavioral management skills necessary both for suc-cessful adoption and maintenance of behaviorchange and for creating social environments thatfacilitate and enhance behavioral change; and

Environmental and policy approaches to change thestructure of physical and organizational environ-ments to provide safe, attractive, and convenientplaces for physical activity.

Within these three categories, the coordination teamgenerated a comprehensive list of candidate interven-tions (Appendix A, Table A-1) for inclusion that ad-dressed each of the modifiable determinants (i.e.,individual level factors, social environment, and physi-cal environment). This list was put in priority order forreview through a process of polling the coordination

team, consultation team,a

and other specialists in thefield about their perception of the public health impor-tance (number of people affected), the practicality ofapplication, and the need of those promoting physicalactivity for information on each intervention. Interven-

aConsultants for the systematic review on increasing physical activitywere Terry Bazzarre, PhD, Robert Wood Johnson Foundation, Prince-ton, NJ; Carl J. Caspersen, PhD, National Center for Chronic DiseasePrevention and Health Promotion, CDC, Atlanta, GA; Diana Cassady,DrPH, California Department of Health Services, Sacramento; Carlos

J. Crespo, DrPH, State University of New York School of Medicineand Biomedical Sciences, Buffalo; Steve Hooker, PhD, CaliforniaDepartment of Health Services, Sacramento; Jonathan Fielding, MD,

MPH, MBA, University of California Los Angeles School of PublicHealth; Barbara Fraser, RD, MS, Nebraska Department of Health andHuman Services, Lincoln; George J. Isham, MD, HealthPartners,Minneapolis, MN; Abby C. King, PhD, Stanford University School ofMedicine, Stanford, CA; I-Min Lee, MD, ScD, Harvard MedicalSchool/Brigham and Womens Hospital, Boston, MA; Denise G.Simons-Morton, MD, PhD, National Heart, Lung, and Blood Insti-tute, National Institutes of Health, Bethesda, MD; Reba A. Norman,MLM, National Center for Chronic Disease Prevention and HealthPromotion, CDC, Atlanta, GA; Cindy Porteous, MA, IndianapolisPark Foundation, Indianapolis, IN; Michael Pratt, MD, MPH, Na-tional Center for Chronic Disease Prevention and Health Promotion,CDC, Atlanta, GA; Thomas Schmid, PhD, National Center forChronic Disease Prevention and Health Promotion, CDC, Atlanta,GA; Christine G. Spain, MA, The Presidents Council on PhysicalFitness and Sports, Washington, DC; Wendell C. Taylor, PhD, MPH,

University of Texas Health Science Center at Houston.


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tions reviewed were either single component (i.e.,using only one activity to achieve desired outcomes) ormulticomponent (i.e., using more than one relatedactivity). Some interventions fell into more than onecategory.

Selection of Outcomes for Review

Many of the studies included in the body of evidencetargeted other behavioral risk factors in addition to

physical inactivity, most often poor diet and smoking.Many of the physiologic benefits observed in thosestudies could be the result of improvements in theseother behaviors rather than improvements in physicalactivity. To be able to estimate the effectiveness of anintervention in increasing physical activity, the teamdecided to base recommendations on changes in phys-ical activity behavior. However, self-reported measure-ment of behavior change, particularly in children, isprone to significant measurement error; objective mea-sures are needed (e.g., heart rate monitoring, acceler-ometers) to enhance reliability and validity.45Addition-

ally, many of the studies did not attempt to measure

behavior even when the intervention targeted behavior,measuring instead physiologic changes as an indicatorof behavior. The team chose to use measures of aerobiccapacity as well as behavioral measures as outcomes on

which recommendations would be based. Aerobic ca-pacity is defined as the maximum amount of oxygenthat can be transported from the lungs to the tissuesduring exercise.46 Maximal oxygen uptake (VO2 max)or a measure of VO2 max is commonly used to measure

changes in fitness level associated with increased activ-ity (behavior change).

Results: Part I. Informational Approaches to


Informational approaches are designed to increasephysical activity by providing information necessary tomotivate and enable people to change their behavior,as well as to maintain that change over time. The focusis mainly on the cognitive skills thought to precedebehavior. The interventions use primarily educational

approaches to present both general health informa-

Figure 1. Logic framework illustrating the conceptual approach used in this review.


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tion, including information about cardiovascular dis-ease prevention and risk reduction, as well as specificinformation about physical activity and exercise. Theseprograms were originally developed to complement amedical model of disease management by involvingcommunities in understanding the cognitive anteced-ents of behavior.

The provision of information is intended to change

knowledge about the benefits of physical activity, in-crease awareness of opportunities within a communityfor increasing physical activity, explain methods forovercoming barriers and negative attitudes about phys-ical activity, and increase participation in community-based activities. Interventions reviewed here are(1) point-of-decision prompts to encourage use ofstairs as an alternative to elevators or escalators,(2) community-wide education campaigns, (3) massmedia campaigns, and (4) classroom-based health ed-ucation focused on information provision and skillsrelated to decision making.

Point-of-Decision Prompts

Point-of-decision prompts are signs placed by elevatorsand escalators to motivate people to use nearby stairs.Messages on the signs recommend stair use for healthbenefits or weight loss. Signs are thought to be effectivein one of two ways: by reminding people alreadypredisposed to becoming more active, for health orother reasons, about an opportunity at hand to be moreactive or by informing them of a health benefit fromtaking the stairs. All interventions evaluated in this

category were single-component interventions, inwhich placement of the sign was the only interventionactivity.

Reviews of evidence

Effectiveness. Our search identified six reports (onepaper reported two studies)4751 on the effectiveness ofpoint-of-decision prompts. All studies were of moderatesuitability, using time-series designs. All were con-ducted between 1980 and 2000. Two of the studies(reported in one paper)49 were of good execution; the

remaining four47,48,50,51 were rated as fair. All wereincluded in the body of evidence. Details of the sixqualifying studies are provided at the website(www.thecommunityguide.org).

Baseline rates of stair use were generally low, with allbut one under 12% (range, 4.8% to 39.6%). In fivestudies4749,51 the median increase in stair-climbing was53.9%. The remaining study50 showed an unspecifiedincrease in stair-climbing and also found that the signs

were effective in getting those who were less active (asmeasured by responses to a brief survey) to take thestairs. The range of effect sizes varied from a 5.5% net

increase to 128.6%.

Applicability. The body of evidence used to evaluatethe applicability of this intervention was the same asthat used to evaluate effectiveness. Four studies wereconducted in the United States,47,49,51 and one studyeach was conducted in England50 and Scotland.48 Thestudies included in this review were implemented inshopping malls,47,49,50 train and bus stations,48,49 and auniversity library.51 Three studies47,48,51 measured ef-

fectiveness separately among men and women andfound that signs were effective in both groups.

Two studies47,49 reported effectiveness separately forobese and nonobese people. Although the signs wereeffective in both groups, the median net increase in thepercentage of people taking the stairs was greateramong the obese group. Among obese people, a signthat linked stair use to the potential for weight lossshowed a higher increase in stair use than the signlinking stair use to general health benefits.

The same two studies47,49 reported results separatelyfor blacks and found mixed evidence of effectiveness.

One study47 showed a decline in the percentage ofblacks taking the stairs when the sign contained ageneric message. A message specifically designed for ablack population, however, was effective in increasingthe percentage of stair users.

This type of intervention is likely to be effectiveacross diverse settings and population groups, providedthat appropriate care is taken to adapt the messages.

Other positive or negative effects. None of the studiesmeasured outcomes other than the percentage of peo-ple using the stairs.

Economic. No studies were found that met the require-ments for inclusion in a Community Guide review.40

Barriers to intervention implementation. Stairways inmany buildings and facilities are often difficult to findand poorly lit, maintained, or secured. As a result theymay appear to be, or actually be, unsafe. Additionally,some stairwells are locked, preventing user access tothem.

Conclusion. According to Community Guide rules ofevidence,39 sufficient evidence shows that point-of-de-cision prompts are effective in increasing levels ofphysical activity, as measured by an increase in thepercentage of people choosing to take the stairs ratherthan an elevator or escalator. Findings from several ofthe studies suggest that tailoring the prompts either byspecifying the benefits of stair use or by customizing thesign to appeal to specific populations may increaseintervention effectiveness.

Community-Wide Campaigns

Community-wide campaigns involve many communitysectors in highly visible, broad-based, multiple interven-

tion approaches to increasing physical activity. In addi-


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tion to addressing sedentary behavior, most of thestudies in this body of evidence also addressed othercardiovascular disease risk factors, particularly diet andsmoking. Communication techniques were a commonelement in all of the campaigns. Campaign messages

were directed to large and relatively undifferentiatedaudiences through diverse media, including television,radio, newspaper columns and inserts, direct mailings,

billboards, advertisements in transit outlets, and trailersin movie theaters. Messages were communicated in theform of paid advertisements, donated public serviceannouncements, press releases, the creation of featureitems, or a combination of two or more of theseapproaches.

In addition to incorporating substantial communica-tion activities through mass media, interventions in thisreview typically included some combination of socialsupport, such as self-help groups; risk factor screening,counseling, and education about physical activity in a

variety of settings, including worksites, schools, andcommunity events; and environmental or policychanges such as the creation of walking trails. Theseinterventions were evaluated as a combined packagebecause it was impossible to distinguish the relativecontributions of each component.

Reviews of evidence

Effectiveness. Our search identified ten reports5261

on the effectiveness of community-wide campaigns. Allstudies were used in the body of evidence. Two stud-

ies52,53

had the greatest suitability of study design andgood execution. The remaining eight studies had fairexecution. Of those, five5458 had the greatest suitabilityof study design and three5961 were of moderate suitabil-ity. Details of the ten qualifying studies are provided atthe website (www.thecommunityguide.org).

Many of the interventions5258 were designed todecrease levels of cardiovascular disease morbidity andmortality throughout a community over a period ofseveral years. Activities were directed both at increasinglevels of physical activity and improving dietary behav-iors. These interventions included many activities sup-

ported by media efforts but conducted independently.In the remaining studies,5961the duration of interven-tion activities ranged from 6 weeks to 6 months, andactivities were more circumscribed, although still pre-sented community-wide.

Six arms from five studies52,53,55,56,60 measuredchange in the percentage of people being active, with amedian net increase of 4.2% (range, 2.9% to 9.4%).Three arms from two studies54,58 measured change inenergy expenditure with a median net increase of16.3% (range, 7.6% to 21.4%). Five arms from fourstudies53,5860 reported other measures of physical ac-

tivity; all but one showed increases in physical activity.

Applicability. The body of evidence used to evaluatethe applicability of this intervention was the same asthat used to evaluate the effectiveness. Five studies wereconducted in the United States,52,54,56,58,59 and onestudy each was conducted in Sweden,57 Denmark,55

Australia,60 Scotland,61 and Wales.53 Studies were con-ducted in rural, suburban, and urban areas and encom-passed all socioeconomic groups. Two studies reported

results for black populations,56,59 and two studies re-ported results for Hispanic or Latino populations.54,59

This type of intervention is likely to be effectiveacross diverse settings and population groups, providedthat appropriate care is taken to adapt the interven-tions to the target populations.

Other positive or negative effects. Seven arms fromfive studies5254,56,59 examined weight change amongpeople in the communities receiving the interventions.Measures included body mass index (BMI), weight,relative weight (i.e., ideal weight/actual weight), and

the percentage of people who were overweight. Threearms from three separate studies52,56,59 showed weightlosses, two arms from two studies52,54 showed nochanges, and two arms from one study53 showed slight

weight gains over the course of the intervention. Acrossthe body of evidence, the net decrease in weight was0.6%. Four arms from two studies54,58 reported positivechanges in knowledge about exercise, with a medianincrease of 19.9%. Three studies55,61,62 with seven studyarms reported physical activity intentions, that is, thepercentage of people either intending to increaseactivity or actually doing so. Five of the arms reported

an increase in intention to increase physical activity,one showed no change, and one reported a decrease.In addition to increased physical activity, other

health benefits may result from the interventions. Mostof the studies in this body of evidence also addressedother cardiovascular disease risk behaviors, particularlydiet and smoking. Although these results were notsystematically reviewed, improvements were evident insome studies. Community-wide education campaignsmay also produce other benefits that can improvehealth and build social capital in communities. Forexample, through working together communities may

develop a greater sense of cohesion and collectiveself-efficacy. Social networks may also be developed orstrengthened to achieve intervention goals, and com-munity members may become involved in local govern-ment and civic organizations, thereby increasing socialcapital.


Barriers to intervention implementation. Community-wide campaigns require careful planning and coordi-nation, well-trained staff, and sufficient resources to

carry out the campaign as planned. Success is greatly


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enhanced by community buy-in, which can take a greatdeal of time and effort to achieve. Insufficient resourcesmay result in exposure to messages and other plannedcampaign interventions that is inadequate to achievethe doses necessary to change knowledge, attitudes,or behavior over time, especially among high-risk pop-ulations. Inadequate resources and lack of profession-ally trained staff may affect how completely and appro-

priately interventions are implemented and evaluated.

Conclusion. According to Community Guide rules ofevidence,39 strong evidence exists that community-widecampaigns are effective in increasing levels of physicalactivity, as measured by an increase in the percentage ofpeople engaging in physical activity, energy expendi-ture, or other measure of physical activity.

Mass Media Campaigns

Mass media campaigns are interventions that address

messages about physical activity to large and relativelyundifferentiated audiences. The campaigns are de-signed to increase knowledge, influence attitudes andbeliefs, and change behavior. Messages are transmittedby using channels such as newspapers, radio, television,and billboards singly or in combination. In this review,interventions that use mass media and include othercomponents (e.g., support groups, risk factor screeningand education, and community events) are classified ascommunity-wide campaigns and are discussed else-

where (see Community-Wide Campaigns section).

Reviews of evidence

Effectiveness. Our search identified three stud-ies54,59,63 evaluating the effectiveness of mass mediacampaigns. All studies had fair execution. The studydesigns were a nonrandomized community trial,54 atime-series,59 and a before-and-after design with noconcurrent comparison group.63 These designs wererated as having greatest, moderate, and least suitablestudy designs, respectively. Details of the three qualify-ing studies are provided at the website(www.thecommunityguide.org).

Effectiveness measures were (1) the change in thepercentage of people doing a specified level of activity(i.e., walking, moderate- and vigorous-intensity physicalactivity, aerobic and nonaerobic activity),59,63

(2) change in energy expenditure,54 and (3) the per-centage of the population categorized as sedentary.63

Overall, some but not all measures suggested a modesttrend toward increasing physical activity, especially atlower levels of physical activity. According to CommunityGuide rules of evidence,39 we concluded that, becauseof small numbers of available studies and limitations inthe designs and execution of the available studies,

insufficient evidence was available to assess the effec-

tiveness of mass media campaigns, when used alone, toincrease physical activity or improve fitness.

Applicability. Evidence about applicability was not as-sessed for this intervention because effectiveness wasnot established.

Other positive or negative effects. Two studies54,59

examined the effects of mass media campaigns onadiposity: One59 showed a decrease in weight over the3-month intervention period and the other54 found noeffect. Significant and substantial improvements inknowledge and beliefs were seen in two studies.54,63

Mass media campaigns might play important roles inchanging awareness of opportunities for and benefits ofphysical activity, helping to build support for environ-mental and policy changes that improve physical activ-ity behavior and fitness, or both. Our reviews, however,did not assess the effect of mass media campaigns onsuch outcomes.

Economic. Evidence about economic effectiveness wasnot collected because effectiveness of the intervention

was not established.

Barriers to intervention implementation. Evidenceabout barriers to implementation of this intervention

was not collected because effectiveness was notestablished.

Conclusion. Available studies provide insufficient evi-dence to assess the effectiveness of mass media cam-paigns, when used alone, to increase physical activity orimprove fitness. Media campaigns are, however, a com-ponent of other effective interventions (see Communi-ty-Wide Campaigns section) and might provide addi-tional benefits. Until more and better informationbecomes available, communities might choose to makedecisions about the use of education-only programs ongrounds other than the evidence found in availablestudies.

Classroom-Based Health Education Focused onInformation Provision

Health education classes that provide information and

skills related to decision making are usually multicom-ponent, with the curriculum typically addressing phys-ical activity, nutrition, smoking, and cardiovasculardisease. Health education classes, taught in elementary,middle, or high schools, are designed to effect behaviorchange through personal and behavioral factors thatprovide students with the skills they need for rationaldecision making. Many of the classes in the studiesreviewed had a behavioral skills component (e.g., role-play, goal-setting, contingency planning) but did notadd time spent in physical activity to the curriculum. Inmost cases, comparison groups received the standard

health education curriculum.


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Reviews of evidence

Effectiveness. Our search identified 13 studies6476

evaluating the effectiveness of classroom-based healtheducation focused on information provision. Of these,three studies had limited quality of execution and werenot included in our review.7476 The ten remainingstudies had greatest suitability of study design. One had

good execution64

and nine had fair execution.6573

Details of the ten qualifying studies are provided at thewebsite (www.thecommunityguide.org).

Most of the interventions were designed to reducethe risk of developing chronic disease. Four interven-tions65,7173 were designed with the use of the Know

Your Body curriculum. (The Know Your Body curricu-lum is designed to provide children with the skillsneeded to adopt behaviors that reduce the risk ofdeveloping cardiovascular disease. The classes focus onnutrition, physical fitness, and preventing cigarettesmoking.) One intervention68 focused on prevention of

type 2 diabetes by encouraging students to eat low-fatfoods and to exercise regularly. The duration of theintervention activities ranged from 3 months to 5 years.

The studies reviewed showed variable effects of theseinterventions on time spent in physical activity outsidethe school setting: three study arms from two studiesshowed increases in activity,6668 and five study armsfrom two studies showed decreases in self-reportedactivity.64,66 Other measures of physical activity werealso varied: five study arms from one study foundpositive changes in self-reported behavior,66 and 11study arms from two studies found no change or

negative changes in self-reported behavior.64,66

Aerobiccapacity was not measured in any of these studies.


Other positive or negative effects. Although thesestudies did not show changes in activity, four of fivestudy arms from three studies showed increases ingeneral health knowledge, exercise-related knowledge,and self-efficacy about exercise.64,67,68 Effects on adi-posity were mixed,69 showing decreases in BMI among

both boys and girls but decreases in skinfold measure-ments among boys only.

Economic. Evidence about economic effectiveness wasnot collected because effectiveness of the intervention




Conclusion. According to Community Guide rules of

evidence,39 the studies reviewed provided insufficient

evidence to assess the effectiveness of classroom-basedhealth education focused on information provision inincreasing levels of physical activity or improving fitnessbecause of inconsistent results among studies.

Results. Part II. Behavioral and Social Approaches to


Behavioral and social approaches focus on increasingphysical activity by teaching widely applicable behav-ioral management skills and by structuring the socialenvironment to provide support for people trying toinitiate or maintain behavior change. Interventionsoften involve individual or group behavioral counselingand typically include the friends or family membersthat constitute an individuals social environment. Skillsfocus on recognizing cues and opportunities for phys-ical activity, ways to manage high-risk situations, and

ways to maintain behavior and prevent relapse. Inter-ventions also involve making changes in the home,family, school, and work environments.

Interventions reviewed here are (1) school-basedphysical education (PE), (2) college-based health edu-cation and PE, (3) classroom-based health educationfocused on reducing television viewing and video gameplaying, (4) family-based social support interventions,(5) social support interventions in community settings,and (6) individually-adapted health behavior changeprograms.

School-Based PE

Interventions that used this approach modified curric-ula and policies to increase the amount of time stu-dents spend in moderate or vigorous activity while inPE classes. This can be done in a variety of ways,including (1) adding new (or additional) PE classes,(2) lengthening existing PE classes, or (3) increasingmoderate to vigorous physical activity (MVPA) of stu-dents during PE class without necessarily lengtheningclass time. Examples of the last approach includechanging the activities taught (e.g., substituting soccerfor softball) or modifying the rules of the game so thatstudents are more active (e.g., having the entire team

run the bases together if the batter makes a hit). Manyof these interventions also included the presentation ofinformation on cardiovascular disease prevention, ren-dering it difficult to separate the effects of healtheducation and modified PE.

Reviews of evidence

Effectiveness. Our search identified 16 articles (onestudy was reported in two papers)7793 reporting on 17studies that evaluated the effectiveness of modifiedschool-based PE curricula and policies. Of these, four

studies had limited quality of execution and were not


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included in our review.78,84,85,92 Twelve of the remain-ing thirteen studies (one study reported in two papers)had greatest suitability of study design.77,7983,8691,93

The remaining study79 had a least suitable design. Fourhad good execution80,81,83,89,93 and nine had fair exe-cution.77,79,82,86 88,90,91 Details of the 13 qualifyingstudies are provided in Appendix B and at www.thecommunityguide.org.

Reported behavioral outcomes were energy expendi-ture,80,81,90 percentage of class time spent inMVPA,80,81,90,91 minutes spent in MVPA,80,81,90,91 ob-served activity score,77,90 and self-reported type andfrequency of physical activities outside ofschool.80,81,86,89,90,94 Eleven studies also reported aero-bic capacity as estimated maximal oxygen uptake (VO2max),77,79 results from timed runs,77,80,81,88,90,93 or en-durance testing (step test or shuttle runs).82,89,93 Thesestudies showed consistent increases in time spent inphysical activity at school. Five arms from four studiesshowed increases in the amount77,91,94 and percent-

age80,81,90,91 of time spent in MVPA in PE classes. Thenet increase in the amount of PE class time spent inMVPA was 50.3% (range, 6.0% to 125.3%; because onestudy91 reported an increase from 0, percentage in-crease from baseline could not be calculated). The netincrease in the percentage of class time in MVPA was10% (range, 3.3% to 15.7%), with an additional studyreporting a 762% increase from a very small baseline

value. Three arms from two studies80,81,90 showed in-creases in energy expenditure as well. Fourteen armsfrom eleven studies77,7984,8890,93 showed increases inaerobic capacity with a median of 8.4% (interquartile

range, 3.1% to 18.9%).

Applicability. The body of evidence used to evaluatethe applicability of this type of intervention was thesame as that used to evaluate effectiveness. Nine studies

were conducted in the United States,77,82,83,86 88,90,91,94

one in Crete,89 and two in Australia.79,93 Ten studies(one study was reported in two papers)77,7981,8691,93

were conducted among elementary school students,and two studies were conducted among high-schoolstudents.82,83 The intervention was successful amongboth elementary and high school students.

Overall results indicate that this type of interventionis likely to be effective across diverse settings andpopulation groups, provided that appropriate care istaken to adapt the intervention to the targetpopulation.

Other positive or negative effects. Ten stud-ies77,79,82,83,88 90,9395 examined weight change. Mea-sures included BMI, skinfold measurements, percent-age of body fat, and weight. BMI estimates mostlyshowed small decreases or no change; one study armshowed a small increase of 1.2%. Skinfold estimatesshowed a median change of 4.4% (interquartile

range, 6.0% to 0.7%). Changes in percentage of

body fat showed inconsistent results, with some in-creases and some decreases.

Indicators of physical fitness other than aerobiccapacity also showed improvements. Flexibility, as mea-sured through sit-and-reach tests, showed improve-ments in two87,89 of three studies.87,89,90 Muscular en-durance also increased in most arms in the twostudies89,90 reporting this measurement; the exception

was for girls performing pull-ups in one study.90 Theseinterventions were also associated with increases inknowledge about exercise,86,87 fitness,89 nutri-tion,80,81,87,88 and general health,83,89 as well as self-efficacy about physical activity.80,81

Although there is a perception that the time spent inPE may harm academic performance, both an exami-nation of the literature included in this review and theresults of a systematic search of other studies on theeffects of PE on academic performance found noevidence of this harm.


Barriers to intervention implementation. The primarybarrier to implementation exists within the schoolsystems. PE is mandated in almost every state, butrequirements for the amount of PE instruction aregenerally low (e.g., four semesters, two to three timesper week or two semesters of daily PE). Few middle andhigh schools require daily PE, and schools face increas-ing pressure to eliminate PE to make more timeavailable for academic subjects.

Conclusion. According to Community Guide rules ofevidence,39 there is strong evidence that school-basedPE is effective in increasing levels of physical activityand improving physical fitness.

College-Based Health Education and PE

College-based health education and PE interventionsaim to set long-term behavioral patterns during thetransition to adulthood. To this end, they use didacticand behavioral education efforts to increase physicalactivity levels among college students. The physicaleducation classes do not have to be offered by PE or

wellness departments in college and university settings,but they do include supervised physical activity in theclass.

The studies in our review included lecture classesthat addressed the benefits and potential risks of phys-ical activity, the current recommendations about theamount and type of physical activity one should get,and behavioral management techniques. Students ap-plied these lessons in laboratory-type sessions in

which they engaged in supervised physical activity,developed goals and activity plans, and wrote termpapers based on their experiences. Students also re-

ceived social support and phone calls from each other


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and made behavioral contracts for an agreed-onamount of physical activity.

Reviews of evidence

Effectiveness. Our search identified five studies (onestudy was reported in two papers)96101 evaluating theeffectiveness of college-based health education and PE

classes. Three96,98,101

of the five studies were not in-cluded in the review of effectiveness because they hadlimited quality of execution. The designs of the tworemaining studies were categorized as greatest suitabil-ity. One study, reported in two papers,99,100 had goodexecution and an initial intervention period of 15

weeks; participants were followed for an additional 2years to examine maintenance of effect after the inter-vention ended. The other study97 was fair in executionand measured a 5-week intervention period. Details ofthe two qualifying studies are provided at the website(www.thecommunityguide.org).

The studies generally showed consistent increases inphysical activity and aerobic capacity in the short term.The 2-year follow-up showed declines in activity back toprevious levels and did not find the desired effects onthe proposed mediators of behavioral change. Accord-ing to Community Guide rules of evidence,39 because ofthe small number of qualifying studies, limitations insome of the studies design and execution, and someinconsistency in the results (with positive results mostlylimited to very short follow-up times), insufficient evi-dence was available to assess the effectiveness of col-lege-based health education and PE interventions to

increase physical activity behavior and fitness.Applicability. Evidence about applicability was not as-sessed for this intervention because effectiveness wasnot established.

Other positive or negative effects. One study, reportedin two papers,99,100 measured effects on several hypoth-esized mediators of behavioral change. Among men,there was some evidence of an increase in the socialsupport of friends and family for physical activity and ofself-efficacy for resisting relapse into physical inactivity.Some evidence was available of a decrease in the

perceived barriers to being physically active. Amongwomen, increases were found in the use of experientialand behavioral processes of change and statisticallynonsignificant increases in enjoyment, social support,self-efficacy, and perceived benefits and barriers.

Economic. Evidence about economic effectiveness wasnot collected for this intervention because effectiveness


Barriers to intervention implementation. Evidenceabout barriers to implementation was not collected forthis intervention because effectiveness was not

established.

Conclusion. Available studies provided insufficient ev-idence to assess the effectiveness of college-basedhealth education and PE interventions to increasephysical activity and fitness.

Classroom-Based Health Education Focused onReducing Television Viewing and Video Game

PlayingIn elementary school classrooms, as part of a generalhealth curriculum, regular classroom teachers taughtclasses that specifically emphasized decreasing theamount of time spent watching television and playing

video games. Classes included instruction in behavioralmanagement techniques or strategies such as self-mon-itoring of viewing behavior, limiting access to televisionand video games, and budgeting time for television and

video. All studies included a TV turnoff challenge inwhich the students were encouraged not to watchtelevision for a specified number of days. Activities that

required greater energy expenditure than watchingtelevision or playing video games were not specificallyrecommended. Parental involvement was a prominentpart of the intervention, and all households were givenautomatic television use monitors.

Reviews of evidence

Effectiveness. Our search identified three studies102104 evaluating health education focused on reducingtelevision viewing and video game playing. All studieshad fair execution and greatest suitability of design,

incorporating a concurrent comparison group andtaking measurements before and after the intervention.Two studies102,103 occurred over a 2-year interventionperiod, and one study104 took place during a 6-monthintervention period. All studies measured the timespent watching television and playing video games asthe primary outcome of interest. One study104 alsomeasured time spent in other sedentary behavior. Themain effectiveness measure from these studies used inour review was the time spent in vigorous,103 moderateor vigorous,102 or unspecified104 physical activity perday.

The studies showed a consistent and sizable decreasein television viewing and video game playing for bothboys and girls according to childrens self-report102104

and parental report.104 Time spent in other sedentarybehaviors also decreased in a single study.104 Reduc-tions in television viewing and video game playing didnot, however, consistently correspond with increases inphysical activity. Six measures of physical activityshowed inconsistent results, with two measures showingincreases and four measures showing decreases.

According to Community Guide rules of evidence,39

available studies provide insufficient evidence to assess

the effectiveness of health education classes focused on


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reducing television viewing and video game playing toincrease physical activity behavior, because of inconsis-tent results for that outcome.


Other positive or negative effects. Two of the stud-

ies102,104 examined effects on adiposity. One study104showed significant decreases in both BMI (2.3%) andskinfold measurements (11.5%). One study102 showeda 24.2% reduction in the prevalence of obesity amonggirls and no change among boys, as well as higher ratesof obesity remission in the intervention group com-pared with the control group. (Obesity remission oc-curs when a child who is defined as obese grows intohis or her weight: body weight does not decrease butthe child grows in height, thus reducing the BMI to alevel that is no longer considered obese.) Because there

was no evidence of effect on levels of physical activity, it

is thought that reductions in adiposity might be theresult of lower levels of snacking while watching televi-sion. An alternative explanation is that the interven-tions caused an increase in light physical activity that

was not captured by the methods used.

Economic. Evidence about economic effectiveness wasnot collected for this intervention because effectiveness



was not collected because effectiveness was not

established.

Conclusion. Available studies provide insufficient evi-dence to assess the effectiveness of classroom-basedhealth education focused on reducing television view-ing and video game playing to increase physical activity.Such classes do, however, have additional benefits interms of reducing television watching and may lowerlevels of adiposity. More research is needed into thelinks between reducing time spent watching televisionor playing video games and increasing physical activity.

Family-Based Social SupportFamily-based interventions attempt to change healthbehavior through the use of techniques that increasethe support of family members for behavior change.The family is a major source of influence for childrenin the modeling of health behaviors and is, therefore,an appropriate target for intervention. Many diseaserisk factors, both behavioral and physiologic, aggregate

within families. Moreover, a supportive social environ-ment has been shown to increase maintenance ofbehavior change.

These interventions target factors in the social envi-

ronment and interpersonal and behavioral patterns

that are likely to influence physical activity behaviors.Interventions may be targeted to families with childrenor to spouses or partners without children. Programstypically include joint or separate educational sessionson health, goal-setting, problem-solving, or family be-havioral management and will often incorporate somephysical activities.

Interventions in this category targeted to children

and their families are often implemented as part of alarger strategy that includes other school-based inter-

ventions, such as school-based PE or classroom-basedhealth education. In this setting, the family componentis often conceptualized as an adjunct home curriculumto the school activities, involving take-home packets,reward systems, and family record keeping. They mayalso include family-oriented special events (e.g., theCATCH [Child and Adolescent Trial for CardiovascularHealth] program has Family Fun Nights, which aremini-health fairs for family and peers that offergames, prizes, food, and beverages).

Reviews of evidence

Effectiveness. Our search identified 12 stud-ies67,80,81,8790,105110 on the effectiveness of family-based social support interventions. Of these, one hadlimited quality of execution and was not included inour review. One of the reviewed studies109 had a leastsuitable study design. The remaining 11 stud-ies67,80,81,8790,105108,110 generally indicated no change,

with some studies showing increases in activity andothers showing decreases. This inconsistency of results

across the body of evidence can also be seen in thephysiologic measures. Results were considered incon-sistent because many of the studies had multiple arms

with varying results. Four studies reported an increase inenergy expenditure, and four arms from one study re-ported a decrease in energy expenditure. Both increasesand decreases also were seen in aerobic capacity andflexibility. Details of the 11 qualifying studies are pro-

vided at the website (www.thecommunityguide.org).The 11 studies included in this review can be broadly

divided into those that were implemented as part of aschool-based program67,8790,94,107 and those that were

implemented as independent studies in the communitysetting.105,106,108,110 Studies that were implemented aspart of a school-based program had slightly greaterevidence of effectiveness, but the combination of tech-niques makes it impossible to attribute that success tothe family-based social support intervention. In addi-tion, studies that compared home and school interven-tions with school-only interventions showed no differ-ences in effectiveness.

Applicability. Evidence about applicability was not as-sessed for this intervention because effectiveness was

not established.


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Other positive or negative effects. Eight arms from sixstudies67,8789,107,108 showed increases in knowledgeabout disease risk factors, fitness, exercise, and healthamong both children and adults. One study94 showedevidence of an increase in self-efficacy for physicalactivity. One study108 showed an increase in satisfaction

with the amount of family activity.

Economic. Evidence about economic effectiveness wasnot collected for this intervention because effectivenesswas not established.



Conclusion. According to Community Guide rules ofevidence,39 available studies provide insufficient evi-dence to assess the effectiveness of family-based socialsupport interventions in increasing levels of physical

activity or improving fitness, because of inconsistentresults among the studies.

Social Support Interventions in CommunitySettings

These interventions focus on changing physical activitybehavior through building, strengthening, and main-taining social networks that provide supportive relation-ships for behavior change. This change can be achievedeither by creating new social networks or working

within pre-existing networks in a social setting outsidethe family, such as the workplace. Interventions typi-cally involved setting up a buddy system, making acontract with others to achieve specified levels ofphysical activity, or setting up walking or other groupsto provide companionship and support while beingphysically active.

Reviews of evidence

Effectiveness. Our search identified nine reports59,111118 on the effectiveness of social support interventionsin community settings. All studies were used in the bodyof evidence. One study116 had the greatest suitability of

design and good execution. The remaining eight studieshad fair execution. Of those, seven111115,117,118 had great-est suitability of study design and one59 was of moderatesuitability. Details of the nine qualifying studies are pro-

vided at the website (www.thecommunityguide.org).The typical intervention reviewed involved recruiting

people into voluntary groups in which members pro-vided companionship and support for attaining self-selected activity goals. Each study participant receivedphone calls from other participants and from study staffmembers to monitor progress and to encourage con-tinuation of activities. Some studies involved formal

discussion groups in which barriers to exercise and

negative perceptions about activity were addressed. Themeasured outcomes were varied and included thefrequency and duration of exercise episodes (e.g.,blocks walked daily, flights of stairs climbed daily,frequency of attendance at exercise sessions, frequencyof jogging episodes, participation in exercise and orga-nized sports, or minutes spent in activity).

Five arms from four studies59,111,112,117measured

change in time spent in physical activity with a mediannet increase of 44.2% (interquartile range, 19.9% to45.6%). Six arms from three studies111,114,118 measuredchange in frequency of exercise or physical activity witha median net increase of 19.6% (interquartile range,14.6% to 57.6%). Fitness also improved: five arms fromthree studies111113 showed a median net increase inaerobic capacity of 4.7% (interquartile range, 3.3% to6.1%).

One study116 found that those who received morefrequent support were more active than those whoreceived less frequent support, although both highly

structured and less formal support were equally effec-tive in getting people to be more active.

Applicability. The body of evidence used to evaluatethe applicability of this intervention was the same asthat used to evaluate effectiveness. Seven studies wereconducted in the United States,59,111116 one in Cana-da,118 and one in Australia.117 Six stud-ies59,111,112,115,117,118 were conducted in community set-tings, including community centers and churches. Onestudy was conducted at a worksite113 and two wereconducted in university settings.114,116

Six studies111,112,114 116,118 exclusively or primarilyreported results for women, and three studies59,113,117

also included men in their study populations. Studypopulations for most studies were middle-aged; onestudy111 included women aged 18 years or older, andone study115 focused on older women (aged 50 to 65

years). Three studies111,112,114 restricted their popula-tions to those that were sedentary at the beginning ofthe study; the rest included people at any initial level ofactivity. Given the diversity of countries, settings, andpopulations included in this body of evidence, theseresults should be applicable to diverse settings and

populations, provided appropriate attention is paid toadapting the intervention to the target population.

Other positive or negative effects. Five arms from fourstudies59,111,112,117 reported changes in adiposityamong those enrolled in social support interventions.BMI, waist-to-hip ratio, and percentage of body fat and

weight were measured. Ten of eleven measurementsshowed decreases in adiposity, with a median netchange of 7.3% (interquartile range, 8.1% to6.8%). Four arms from three studies111,112,117 showedincreases in confidence about exercise and in knowl-

edge of and social support for exercise.


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Barriers to intervention implementation. No barrierswere identified to the implementation of social supportin community settings to promote physical activity.

Conclusion. According to Community Guide rules of

evidence,

39

there is strong evidence that social supportinterventions in community settings are effective inincreasing levels of physical activity, as measured by anincrease in the percentage of people engaging inphysical activity, energy expenditure, or other measureof physical activity.

Individually-Adapted Health Behavior ChangePrograms

Individually-adapted health behavior change programsare tailored to the individuals readiness for change,specific interests, and preferences. These programsteach participants specific behavioral skills that enablethem to incorporate moderate-intensity physical activityinto daily routines. Behaviors may be planned (e.g., adaily scheduled walk) or unplanned (e.g., taking thestairs when the opportunity arises). Many or most ofthese interventions use constructs from one or moreestablished health behavior change models such asSocial Cognitive Theory,119 the Health Belief Model,120

or the Transtheoretical Model of Change.121 All pro-grams incorporated the following behavioral approach-es: (1) setting goals for physical activity and self-moni-toring of progress toward goals, (2) building socialsupport for new behavioral patterns, (3) behavioralreinforcement through self-reward and positive self-talk, (4) structured problem-solving geared to mainte-nance of the behavior change, and (5) prevention ofrelapse into sedentary behaviors. All of the interven-tions evaluated were delivered to people either ingroup settings or by mail, telephone, or directed media.

Reviews of evidence

Effectiveness. Our search identified 20 reports on theeffectiveness of individually-adapted health behavior

change programs.60,122140 Of these, two studies138,139had limited quality of execution and were not included inour review. Seven studies had good execution; of these,four,128,130,132,134 two,125,126 and one129 had greatest,moderate, and least suitable study design, respectively.Eleven studies had fair execution.60,122124,127,131,133,135137,140 Of those, seven,60,123,124,127,135137 two,122,133 andtwo131,140 had greatest, moderate, and least suitable de-signs, respectively. Details of the 18 qualifying studies areprovided at the website (www.thecommunityguide.org).

The typical intervention reviewed involved recruitingpeople into voluntary groups working toward physical

activity goals. Members provided companionship and

support for attaining self-selected activity goals. Studyparticipants received phone calls from each other andfrom study staff members to monitor progress and toencourage continuation of activities. Some studies in-

volved formal discussion groups in which barriers toexercise and negative perceptions about activity wereaddressed. The measured outcomes were varied andincluded the frequency and duration of exercise epi-

sodes (i.e., blocks walked daily, flights of stairs climbeddaily, frequency of attendance at exercise sessions,frequency of jogging episodes, participation in exerciseand organized sports, and minutes spent in activity).

Twenty arms from ten studies60,124 128,131,134 136

measured change in the time spent in physical activitywith a median net increase of 35.4% (interquartilerange, 16.7% to 83.3%). Thirteen arms from fourstudies125,126,132,136 measured change in VO2 max witha median increase of 6.3% (interquartile range, 5.1% to9.8%; Figure 2). Fifteen arms from four studies125127,129 measured change in energy expenditure with anet median increase of 64.3% (interquartile range,31.2% to 85.5%). Other measures of physical activity,including attendance at exercise sessions,135 the num-ber of prescribed exercise sessions completed,132 thepercentage of people starting exercise programs,122

and the frequency of physical activity60,136 increased aswell.

Although we did not attempt a single quantitativesummary across the diverse effect measures becausethey could not be transformed to the same scale, theresults of the various effect measures support a gener-

ally similar narrative conclusion: the preponderance ofthe evidence suggests that this type of intervention iseffective in increasing physical activity.

Applicability. The body of evidence used to evaluatethe applicability of this intervention was the same asthat used to evaluate effectiveness. Seventeen studies

were conducted in the United States122137,140 and onein Australia.60 Fourteen studies were conducted incommunity settings.60,123134,140 Four studies were con-ducted at worksites,59,112,122,125 two at schools or uni-

versities,135,136 and one at a telecommunications

company.137

These studies typically included volunteer samples,which limit generalizing to the entire population.Three studies123,124,131 reported results only for

women. The remainder provided combined results formen and women. Study populations for most studies

were middle-aged; four studies128,130,132,135 focused onpeople age 50 years or older.

Given the diversity of settings and populations in-cluded in this body of evidence, these results should beapplicable to diverse settings and populations, providedappropriate attention is paid to adapting the interven-

tions to the target populations.


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Other positive or negative effects. Fourteen of sixteenmeasurements from six studies125,126,129,131,140,141 re-ported a decrease in body weight, with a median net

change of

3.9% (interquartile range,

7.2% to

0.7%).All six measurements from three studies125,126,141 re-ported a decrease in percentage of body fat, with amedian of 4.1% (interquartile range, 5.9% to2.3%). Seven of nine measurements from two stud-ies130,141 reported an increase in strength, with a medianof 7.8% (interquartile range, 4.1% to 11.0%). Two mea-surements from two studies130,141 reported an increase inflexibility.

Economic. Our search identified one economic evalu-ation of individually-adapted health behavior changeprograms. This 2-year study,142 conducted at a fitness

facility in Dallas, Texas, evaluated the cost-effectivenessof two physical activity interventions (lifestyle and struc-tured interventions) provided to adults aged 35 to 60

years. The lifestyle intervention consisted of behavioralskills training to integrate moderate-to-intense physicalactivity into the lives of participants. Behavior modifi-cation and cognitive-behavior modification techniques

were used for behavior change. The structured exerciseintervention consisted of supervised center-based exer-cise, in which participants received an exercise intensityprescription of 50% to 85% of maximum aerobic powerand exercise of 20 to 60 minutes at each session.

Outcome measures included energy expenditure, mod-

erate activity and hard activity (kilocalories per kilo-gram per day), sitting (hours per week), walking (min-utes per day), stair climbing (flights per day), VO2 max

(milliliters per kilogram per minute), and treadmilltime (minutes). The effect size for these outcomemeasures ranged between 0.23 (additional minutes onthe treadmill) and 13.07 (walking minutes per day),and 0.33 (additional kilocalorie per kilogram expendi-ture of moderate activity) to 26.75 (walking minutesper day for lifetime and structured interventions).Program costs included personnel, capital equipment,facilities, and general supplies, but research costs, re-cruitment costs, and value of participants time werenot included. The adjusted cost-effectiveness ratio foreach intervention arm ranged between $0.05 to $3.94

and $0.07 to $5.39 per average unit (as defined in theoutcomes measured above) of improvement for life-style and structured intervention, respectively. Thisstudy was classified as good, based on the qualityassessment criteria used in the Community Guide.40 Theeconomic summary table for the study is provided in

Appendix A, Table A-3, and at the website(www.thecommunityguide.org).

Barriers to intervention implementation. Individually-adapted health behavior change programs requirecareful planning and coordination, well-trained staffmembers, and resources sufficient to carry out the

program as planned. Inadequate resources and lack of

Figure 2. Individually-adapted health behavior change: net percentage change in maximal oxygen consumption (VO2 max)from baseline in individuals being taught health behavior change strategies.con, control; ex, exercise; inten, intensity; lo, low; v, versus.


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professionally trained staff members may affect howcompletely and appropriately interventions are imple-mented and evaluated.

Conclusion. According to Community Guide rules ofevidence,39 there is strong evidence that individually-adapted health behavior change programs are effectivein increasing levels of physical activity, as measured by

an increase in the percentage of people engaging inphysical activity, energy expenditure, or other measureof physical activity.

Results. Part III. Environmental and Policy

Approaches to Increasing Physical Activity

Environmental and policy approaches are designed toprovide environmental opportunities, support, andcues to help people develop healthier behaviors. Thecreation of healthful physical and organizational envi-ronments is attempted through development of policy

that lends itself to creating supportive environmentsand strengthening community action. Correlationalstudies have shown that physical activity levels areassociated with factors such as the availability of exer-cise equipment in the home and the proximity anddensity of places for physical activity within neighbor-hoods. Other neighborhood and environmental char-acteristics such as safety lighting, weather, and airpollution also affect physical activity levels, regardless ofindividual motivation and knowledge.

To affect entire populations, interventions in thiscategory are not directed to individuals but rather to

physical and organizational structures. The interven-tions are implemented and evaluated over a longerperiod of time than more individually oriented inter-

ventions. Interventions are conducted by traditionalhealth professionals, but they also involve many sectorsthat have not previously been associated with publichealth, such as community agencies and organizations,legislators, and the mass media. The goal is to increasephysical activity through changing social networks, or-ganizational norms and policies, the physical environ-ment, resources and facilities, and laws. In addition tothe intervention reviewed below, two more interven-

tions to increase physical activity by using environmen-tal and policy approaches (i.e., [1] transportation pol-icies and infrastructure changes to promotenonmotorized transit and [2] urban planning ap-proacheszoning and land use) are under way and willbe included in a subsequent report.

Creation of or Enhanced Access to Places forPhysical Activity Combined with InformationalOutreach Activities

These interventions involve the efforts of worksites,

coalitions, agencies, and communities to create or

provide access to places and facilities where people canbe physically active. For example, interventions in thebody of evidence include providing access to weightand aerobic fitness equipment in fitness centers orcommunity centers, creating walking trails, and provid-ing access to nearby fitness centers.

In addition to promoting access, many of thesestudies incorporated components such as training on

equipment, health behavior education and techniques,seminars, counseling, risk screening, health forums and

workshops, referrals to physicians or additional ser-vices, health and fitness programs, and support orbuddy systems. These multicomponent interventions

were evaluated together because it was not possible toseparate out the incremental benefits of eachcomponent.

Reviews of evidence

Effectiveness. Our search identified a total of 12 stud-

ies

143154

evaluating the effectiveness of creation of orenhanced access to places for physical activity com-bined with informational outreach activities. Of thesestudies, two were excluded because of limited studydesign.146,147 The remaining ten studies all had fairquality of execution, seven had greatest suitability ofstudy design,143145,148,150,153,154 and three had leastsuitability of study design.149,151,152 Details of the tenqualifying studies are provided at the website(www.thecommunityguide.org).

Eight arms from five studies144,150,151,153,154 mea-sured change in aerobic capacity: the median increase

was 5.1% (interquartile range, 2.8% to 9.6%). Threearms from two studies144,153 measured change in en-ergy expenditure: the median increase was 8.2%(range, 2.0% to 24.6%). Four arms from two stud-ies145,148 measured change in the percentage reportingsome leisure-time physical activity: the median increase

was 2.9% (interquartile range, 6.0 to 8.5%). Six armsfrom one study152 measured exercise score: the medianincrease was 13.7% (interquartile range, 1.8% to69.6%). Four arms from three studies143,148,151 mea-sured the percentage reporting three or more exercisesessions per week, and two studies149,150 measured

frequency of physical activity (Figure 3); the medianincrease was 48.4% (interquartile range, 21.0% to83.8%). Although we did not attempt a single quanti-tative summary across the diverse effect measures be-cause they could not be transformed to the same scale,the results of the various effect measures support agenerally similar narrative conclusion: the preponder-ance of the evidence suggests that this type of interven-tion is effective in increasing physical activity.

Applicability. All of the studies were conducted in theUnited States. Eight studies were conducted at work-sites, which included industrial plants (automotive,

brewing, printing), universities, and federal agen-


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cies.143,144,148 151,153,154 Two studies were conducted in

low-income communities.

145,152

One study includedonly men150 and two studies stratified for men andwomen.145,152 One study152 included only blacks, andone study reported results specific to blacks.145 Giventhe diversity of settings and populations included inthis body of evidence, these results should be applicableto diverse settings and populations, provided appropri-ate attention is paid to adapting the intervention to thetarget population.

Other positive or negative effects. Ten arms from sixstudies145,148150,153,154 examined weight change. Mea-sures included percentage of body fat, weight, and

percentage of people who were overweight. Nine armsfrom the same six studies showed decreases in percent-age of body fat or weight losses.145,148 150 One armfrom one study148 showed a weight gain. One studyshowed improvements in strength and improvementson the Physical Readiness Test composite score.153 Onestudy154 showed improvements in flexibility. Onestudy150 showed increases in perceived energy andconfidence in the ability to exercise regularly.

In addition to the direct health benefits in terms ofphysical activity, other health benefits also may haveresulted from the intervention. Many of the studies in

this body of evidence also addressed cardiovascular

disease risk factors, particularly diet and smoking,

through provision of information.Economic. Our search identified two economic evalu-ations155,156 of interventions to create or enhance ac-cess to places for physical activity. One 4-year study155

conducted at fitness facility in Houston, Texas, foremployees of an insurance company conducted a costbenefit analysis of a structured physical fitness program.The program included regularly scheduled classes inaerobic dancing, calisthenics, and jogging; seminars onobesity, smoking, alcohol abuse, and stress reductionalso were offered. Program benefits included savings inmajor medical costs, reduction in average number of

disability days, and reduction in direct disability dollarcosts. Program costs included personnel, nonsalaryoperating expenses, and medical claims. The adjustedestimates for benefits and costs for 1 year of theprogram are $1106 and $451, respectively. On the basisof the quality assessment criteria used in the CommunityGuidethis study was classified as good.40 The economicsummary table for the study is provided at the website(www.thecommunityguide.org).

A 5-year study156with projections for an additional 10years was conducted in a workplace setting among36,000 employees and retirees of an insurance com-

pany. The researchers conducted a cost benefit analy-

Figure 3. Creation of or enhanced access to places for physical activity combined with informational outreach: net percentagechange from baseline in frequency of physical activity.PA, physical activity.


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sis of a company-sponsored health and fitness programthat used health promotion centers, newsletters, medi-cal reference texts, videotapes, and quarterly mediablitzes. Program benefits included cost savings fromhealthcare costs averted, absenteeism reduction, deathsaverted, and increased productivity. Program costs in-cluded personnel, overhead, capital equipment, mate-rials, and rent; employee time away from the job was

not included as a program cost. The adjusted estimatesfor benefits and costs are $139 million and $43 million,respectively. On the basis of the quality assessmentcriteria used in the Community Guide, this study wasclassified as good.40

Barriers to intervention implementation. One poten-tial barrier to creation of or enhanced access to placesfor physical activity is that building new facilities is timeand resource intensive. In addition, creation of orenhanced access to facilities requires careful planningand coordination, as well as resources sufficient to carry

out the construction. Success is greatly enhanced bycommunity buy-in, which can take a great deal of timeand effort to achieve. Inadequate resources and lack ofprofessionally trained staff members may affect howcompletely and appropriately interventions are imple-mented and evaluated.

Conclusion. According to Community Guide rules ofevidence,39 there is strong evidence that creation of orenhanced access to places for physical activity com-bined with informational outreach activities is effectivein increasing levels of physical activity, as measured byan increase in the percentage of people engaging in

physical activity or other measures of physical activity.

Research Issues

Informational Approaches to Increasing PhysicalActivity

Effectiveness. The effectiveness of recommended andstrongly recommended interventions in this section(i.e., community-wide campaigns and point-of-decisionprompts) is established. However, important researchissues about the effectiveness of these interventionsremain.

Point-of-decision prompts

What is the sustained effect of placing signs near theelevator or escalator?

What effect does varying the message or format of thesign have on providing a booster to stair climbingamong the targeted population?

What type of sign is most effective? What effect doformat or size have, if any?

Does effectiveness vary by setting and targetaudience?

Is there a critical distance from the elevator or

escalator to the stairs in which the effect of signageon stair-climbing behavior is reduced?

Because the effectiveness of mass media campaigns andclassroom-based health education focused on informa-tion provision has not been established, basic researchquestions remain.

Are these interventions effective in increasing physi-

cal activity? Do these interventions promote positive or negative

attitudes toward physical activity? Do these interventions promote changes in physical

activity mediators, such as stage of change or changesin policy, which may lead to population shifts?

Community-wide campaigns

What characteristics and components of community-wide campaigns are most effective?

How can community-wide efforts be institutionalized?

What are the most effective and efficient deliverysettings and channels (e.g., media, work settings)?

Do coalitions enhance the delivery and effectivenessof interventions in community settings? If so, is theenhanced effect worth the potential added cost andburdens of implementation?

Behavioral and Social Approaches to IncreasingPhysical Activity

Effectiveness. The effectiveness of recommended andstrongly recommended interventions in this section(i.e., school-based PE, social support interventions incommunity settings, individually-adapted health behav-ior change programs) is established. However, researchissues about the effectiveness of these interventionsremain.

School-based PE

Is school-based PE as effective for preschool, elemen-tary, and high school students as for middle schoolstudents?

Is effectiveness of school-based PE different in coedclasses versus single-sex classes in junior high and

high school? Are classroom teachers as effective as PE specialists? What is the relationship between PE class and overall

daily physical activity? Is activity outside the schoolsetting reduced when activity in PE is increased?

Are before-school and after-school PE programs ef-fective in increasing students total daily activity levelsor improving fitness?

Does physical activity incorporated into regularclasses result in effects similar to physical activityincorporated in a dedicated PE class?

Is the effectiveness or efficacy of school-based PE

affected by school setting (e.g., type of school, urban,


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suburban, etc.) or by population served (e.g., lowersocioeconomic status, racial or cultural differences)?

Social support interventions in communitysettings

What type of social support and what medium worksfor whom? Do intensity and structure of the support

make a difference? How does effect size vary by frequency of social

interaction? Does the effect of these interventions vary by gender?

Individually-adapted health behavior change

What characteristics and components are mosteffective?

What mode of delivery is most effective? Does the effectiveness of behavioral change method

vary by type of physical activity?

Because the effectiveness of college-based health edu-cation and PE, classroom-based health education fo-cused on reducing television viewing and video gameplaying, and family-based social support has not beenestablished, basic research questions remain.

Are these interventions effective in increasing physi-cal activity?

Do these interventions promote positive or negativeattitudes toward physical activity?

Environmental and Policy Approaches to


Effectiveness. The effectiveness of the strongly recom-mended intervention in this section (i.e., creation of orenhanced access to places for physical activity) is estab-lished. However, research issues about the effectivenessof these interventions remain.

What characteristics of a community are necessary forthe optimal implementation of policy and environ-mental interventions?

Does the effectiveness vary by type of access (e.g.,worksite facility or community facility) or socioeco-

nomic group? How can the necessary political and societal support

for this type of intervention be created or increased? Does creating or improving access motivate sedentary

people to become more active, give those who arealready active an increased opportunity to be active,or both?

If you build it, will they come? In other words, isenhanced access to places for activity sufficient tocreate higher physical activity levels, or are otherintervention activities also necessary?

What are the effects of creating new places for

physical activity versus enhancing existing facilities?

Which neighborhood features (e.g., sidewalks, parks,traffic flow, proximity to shopping) are the mostcrucial in influencing activity patterns?

How does proximity of places such as trails or parksto residence affect ease and frequency of use?

General Research Issues

Effectiveness. Several crosscutting research issuesabout the effectiveness of all of the reviewed interven-tions remain.

What behavioral changes that do not involve physicalactivity can be shown to be associated with changes inphysical activity? For example, does a decrease intime spent watching television mean an increase inphysical activity or will another sedentary activity besubstituted? Does an increase in the use of publictransportation mean an increase in physical activityor will users drive to the transit stop?

Physical activity is difficult to measure consistently

across studies and populations. Although severalgood measures have been developed, several issuesremain to be addressed.

Reliable and valid measures are needed for thespectrum of physical activity.

Rationale: Current measures are better for vigor-ous activity than for moderate or light activity.Sedentary people are more likely to begin activityat a light level; this activity is often not captured bycurrent measurement techniques.

Increased consensus about best measures for phys-

ical activity would help to increase comparabilitybetween studies and would facilitate assessment ofeffectiveness.

Note: This is not intended to preclude researcherslatitude in choosing what aspects of physical activityto measure and to decide which measures are mostappropriate for a particular study population. Per-haps a useful middle ground position would be theestablishment of selected core measures that mostresearchers should use which could then be supple-mented by additional measures. The duration of an

interventions effect was often difficult to determine.Although some researchers did attempt long-termfollow-up and assessment, many questions remain.

How long does the effect of an intervention endureafter intervention activities cease?

Does the duration of an intervention affect themaintenance of activity? For example, does a 2-yearintervention show effectiveness for a longer periodafter the intervention ends than a 10-week interven-tion? What strategies can be used to maintain anintervention effect after the intervention ends? Areperiodic boosters necessary or helpful?

What is the nature and role of program champions


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in ensuring the successful implementation and adop-tion of an intervention?

Applicability. Each recommended and strongly recom-mended intervention should be applicable in mostrelevant target populations and settings, assuming thatappropriate attention is paid to t

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