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An assessment of schoolyard renovation strategies to encourage children’s physical activity

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Title:
An assessment of schoolyard renovation strategies to encourage children’s physical activity
Series Title:
International Journal of Behavioral Nutrition and Physical Activity 8 (1):27.
Creator:
Anthamatten, Peter ( Author, Primary )
Brink, Lois
Lampe, Sarah
Greenwood, Emily
Kingston, Beverly
Nigg, Claudio
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BioMed Central
International Journal of Behavioral Nutrition and Physical Activity
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English
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Journal Article

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Abstract:
Background: Children in poor and minority neighborhoods often lack adequate environmental support for healthy physical development and community interventions designed to improve physical activity resources serve as an important approach to addressing obesity. In Denver, the Learning Landscapes (LL) program has constructed over 98 culturally-tailored schoolyard play spaces at elementary schools with the goal to encourage utilization of play spaces and physical activity. In spite of enthusiasm about such projects to improve urban environments, little work has evaluated their impact or success in achieving their stated objectives. This study evaluates the impacts of LL construction and recency of renovation on schoolyard utilization and the physical activity rates of children, both during and outside of school, using an observational study design. Methods: This study employs a quantitative method for evaluating levels of physical activity of individuals and associated environmental characteristics in play and leisure environments. Schools were selected on the basis of their participation in the LL program, the recency of schoolyard renovation, the size of the school, and the social and demographic characteristics of the school population. Activity in the schoolyards was measured using the System for Observing Play and Leisure Activity (SOPLAY), a validated quantitative method for evaluating levels of physical activity of individuals in play and leisure environments. Trained observers collected measurements before school, during school recess, after school, and on weekends. Overall utilization (the total number of children observed on the grounds) and the rate of activity (the percentage of children observed who were physically active) were analyzed. Observations were compared using t-tests and the data were stratified by gender for further analysis. In order to assess the impacts of LL renovation, recently-constructed LL schoolyards were compared to LL schoolyards with older construction, as well as un-renovated schoolyards. Results: Overall utilization was significantly higher at LL schools than at un-renovated schools for most observation periods. Notably, LL renovation had no impact on girl’s utilization on the weekends, although differences were observed for all other periods. There were no differences in rates of activity for any comparison. With the exception of the number of boys observed, there was no statistically significant difference in activity when recentlyconstructed LL schools are compared to LL schools with older construction dates and there was no difference observed in comparisons of older LL with unrenovated sites. Conclusions: While we observed greater utilization and physical activity in schools with LL, the impact of specific features of LL renovation is not clear. However, schoolyard renovation and programs to encourage schoolyard use before and after school may offer a means to encourage greater physical activity among children, and girls in particular. Additional study of schoolyard renovation may shed light on the specific reasons for these findings or suggest effective policies to improve the physical activity resources of poor and minority neighborhoods.
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Collected for Auraria Institutional Repository by the Self-Submittal tool. Submitted by Peter Anthamatten.
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Copyright Peter Anthamatten. Permission granted to University of Colorado Denver to digitize and display this item for non-profit research and educational purposes. Any reuse of this item in excess of fair use or other copyright exemptions requires permission of the copyright holder.

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RESEARCH OpenAccessAnassessmentofschoolyardrenovation strategiestoencouragechildren sphysical activityPeterAnthamatten1*,LoisBrink2,SarahLampe3,EmilyGreenwood2,BeverlyKingston4andClaudioNigg5AbstractBackground: Childreninpoorandminorityneighborhoodsoftenlackadequateenvironmentalsupportforhealthy physicaldevelopmentandcommunityinterventionsdesignedtoimprovephysicalactivityresourcesserveasan importantapproachtoaddressingobesity.InDenver,theLearningLandscapes(LL)programhasconstructedover 98culturally-tailoredschoolyardplayspacesatelementaryschoolswiththegoaltoencourageutilizationofplay spacesandphysicalactivity.Inspiteofenthusiasmaboutsuchprojectstoimproveurbanenvironments,littlework hasevaluatedtheirimpactorsuccessinachievingtheirstatedobjectives.ThisstudyevaluatestheimpactsofLL constructionandrecencyofrenovationonschoolyardutilizationandthephysicalactivityratesofchildren,both duringandoutsideofschool,usinganobservationalstudydesign. Methods: Thisstudyemploysaquantitativemethodforevaluatinglevelsofphysicalactivityofindividualsand associatedenvironmentalcharacteristicsinplayandleisureenvironments.Schoolswereselectedonthebasisof theirparticipationintheLLprogram,therecencyofschoolyardrenovation,thesizeoftheschool,andthesocial anddemographiccharacteristicsoftheschoolpopulation.Activityintheschoolyardswasmeasuredusingthe SystemforObservingPlayandLeisureActivity(SOPLAY),avalidatedquantitativemethodforevaluatinglevelsof physicalactivityofindividualsinplayandleisureenvironments.Trainedobserverscollectedmeasurementsbefore school,duringschoolrecess,afterschool,andonweekends.Overallutilization(thetotalnumberofchildren observedonthegrounds)andtherateofactivity(thepercentageofchildrenobservedwhowerephysically active)wereanalyzed.Observationswerecomparedusingt-testsandthedatawerestratifiedbygenderforfurther analysis.InordertoassesstheimpactsofLLrenovation,recently-constructedLLschoolyardswerecomparedtoLL schoolyardswitholderconstruction,aswellasun-renovatedschoolyards. Results: OverallutilizationwassignificantlyhigheratLLschoolsthanatun-renovatedschoolsformostobservation periods.Notably,LLrenovationhadnoimpactongirl sutilizationontheweekends,althoughdifferenceswere observedforallotherperiods.Therewerenodifferencesinratesofactivityforanycomparison.Withtheexception ofthenumberofboysobserved,therewasnostatisticallysignificantdifferenceinactivitywhenrecentlyconstructedLLschoolsarecomparedtoLLschoolswitholderconstructiondatesandtherewasnodifference observedincomparisonsofolderLLwithunrenovatedsites. Conclusions: WhileweobservedgreaterutilizationandphysicalactivityinschoolswithLL,theimpactofspecific featuresofLLrenovationisnotclear.However,schoolyardrenovationandprogramstoencourageschoolyarduse beforeandafterschoolmayofferameanstoencouragegreaterphysicalactivityamongchildren,andgirlsin particular.Additionalstudyofschoolyardrenovationmayshedlightonthespecificreasonsforthesefindingsor suggesteffectivepoliciestoimprovethephysicalactivityresourcesofpoorandminorityneighborhoods. *Correspondence:peter.anthamatten@ucdenver.edu1DepartmentofGeographyandEnvironmentalSciences,Universityof ColoradoDenver,Denver,CO,USA FulllistofauthorinformationisavailableattheendofthearticleAnthamatten etal InternationalJournalofBehavioralNutritionandPhysicalActivity 2011, 8 :27 http://www.ijbnpa.org/content/8/1/27 2011Anthamattenetal;licenseeBioMedCentralLtd.ThisisanOpenAccessarticledistributedunderthetermsoftheCreative CommonsAttributionLicense(http://creativecommons.org/licenses/by/2.0),whichpermitsunrestricteduse,distribution,and reproductioninanymedium,providedtheoriginalworkisproperlycited.

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BackgroundObesityhasbecomeanincreasinglytroublesomehealth probleminbothwealthyandpoorregionsaroundthe world[1];theWorldHealthOrganizationreportsthat therearenowoveronebillionoverweightadults,at least300millionofwhomareobese[2].ObesitypresentsaparticularlyalarminghealthconcernintheUnitedStates,whererecentestimatesarethat approximatelyonethirdofchildrenintheUnitedStates areconsideredoverweightorobese[3]. Policydesignedtochange obesogenicenvironments aimstoimplementchangethatbothreduceenergy intake(byencouragingahealthydiet)andprovide opportunitiesforincreasedenergyoutput(byencouragingphysicalactivity)[4].Althoughbehavioralchangeis acriticalcomponenttoaddressingobesity,interventions designedtomodifyindividualbehaviortoreducecaloric intakehavehadlimitedsuccessinpreventingobesityon along-termbasis[3].Altho ughthereisdisagreement aboutwhichsideoftheenergyequationisthemost effectiveintermsofpolicy,extensiveresearchhas demonstratedthatthebuiltenvironmentplaysakey roleinobesity-relatedbehavior(e.g.,[5-8]). Whiletheremaybeonlyaweaktomoderatelink betweenphysicalactivityandobesityrates,thereare numerousadditionalhealth benefitsassociatedwith increasedphysicalactivity.Arecentliteraturereview reportsthatphysicalactivityislinkedwithreduced bloodpressure,lowerlevelsofcholesterolandblood lipids,reducedincidenceofmetabolicsyndrome, increasedbonemineraldensity,aswellasreducedrates ofdepression[9].Understandingtherelationship betweenthebuiltenvironmentandphysicalactivityand thespecificimplicationsofparticularmodificationsto thebuiltenvironmentmaycontributetostrategiesto reduceobesityprevalence[10]inadditiontotheseother healthbenefits. Alongwithtransportationpatternsandland-usepatterns,designfeaturesareoneofthekeyareasofinquiry instudiesofthebuiltenvironmentandphysicalactivity [11-13].Anumberofspecificdesignfeaturespertaining tochildren senvironmentshavebeeninvestigatedin previousresearch.Timespentoutdoors,accessto recreationalfacilitiesandschoolyards[8,14]andproximityandnumberofplayspacesandfacilitiestohome [15]areassociatedwithhigherlevelsofphysicalactivity inchildrenandadolescents.Addinganadditionalrecess periodeachdayisassociatedwithgreaterphysicalactivity[16],whilelimitedoutdoorplaytimehasbeenfound tocorrelatewithahighbodymassindexinyoungchildren[17].Ifitisdesignedwell,theoutdoorbuiltenvironmentcancreateopportunitiesforhealthybehavior changeamongchildren. Comparedtowhitechildren,childrenfromAfricanAmericanandHispanicethnicitiesareparticularlylikely tosufferfromobesity,experienceabnormallyhighglucoselevels,andsufferfromahigherprevalenceofdiabetes[18-20].Theseobservationscouldbeattributedin parttothesocialandbuiltenvironmentsofmanyminoritychildrenlivinginimpoverishedurbanneighborhoods,whichoftenfailtosupporthealthydevelopment andprovidelimitedopportun itiesforhealthybehavior, especiallywithrespecttophysicalactivity.Poorand minoritychildrenoftenhavelimitedaccesstooutdoor playspacesandstructuredopportunitiesforinvolvementinorganizedsportsandotheractivities[19]and aremorelikelytohavelowerfitnesslevels.Thereasons behindthesedisparitiesarenuancedandcomplex,butit mightbepossibletodevelopplanninganddesignpoliciestoaddressgeographicinequality.Someresearchhas shownthatparentsinlow-incomeneighbourhoodshave increasinglyrestrictedtheirchildren sactivityoutof concernsforsafety[21],andthatdesignpoliciescan haveanimpactonthisconcer n[22].Interventionsto improvethesafetyofschoolyardshavebeenshownto improveschoolyardutiliza tion[23].Indeed,communitiesthataredesignedtosupportphysicalactivityhave beenfoundtohave100%higherratesofsufficientphysicalactivitythanthosewithnosupportiveattributes [8].Facetsofthebuiltenvironment,suchasthedensity ofresidences[24],generalwalkability[25],andtheavailabilityofrecreationalspacesandfacilities[26,27]maybe alsolinkedtophysicalactivity,althoughresearchoften yieldsmixedresults[21]. Withtheaveragechildspending1300hoursatschool eachyear,schoolsareavalua blephysicalenvironment andsocialresourceineffortstopromotephysicalactivity. Schoolwellnesspolicies,comm unitybuildinginitiatives, andwalk-to-schoolprograms[21]areafewexamplesof school-basedstrategiesdesignedtoencouragephysical activity.Inspiteofaflourishingbodyofsocial-scientific andpublichealthliteratureexaminingtherelationship betweenphysicalactivityandurbanenvironments,there remainslittleworkthatspecificallyexaminestheimpacts ofrecreationalspacerenovationatschools.Thereisevidencethatrenovatedschoolyardsaremorewidelyused byadultsandchildren(especiallyboys)thanun-renovatedschoolyards[28].Small,inexpensiveinterventions thathavechangedthestructureofthephysicalenvironment,especiallywithinthe schoolenvironment,have shownsignificantpositivecorrelationswithphysical activitylevels.Theseinterventionsincludepaintingthe schoolyards[29],providi nggameequipment[30],and evenincreasingthenumberofballsavailabletoyouth [31].Higherphysicalactivitylevelshavebeenobservedin schoolyardsthathavemulticoloredpaintingcomparedtoAnthamatten etal InternationalJournalofBehavioralNutritionandPhysicalActivity 2011, 8 :27 http://www.ijbnpa.org/content/8/1/27 Page2of9

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thosewithout[32].Theincorporationofculturally-tailoredschoolyardelementsmayalsoencouragephysical activityandultimatelycontributetothereductionofobesity[33],whichisespeciallyimportantincommunities withlargeethnicminoritypopulations.Inastudythat usedthesameobservationmethodasthecurrentone, Sallisetal.concludethatmakingimprovementstoschool environmentscouldincreasethephysicalactivityofstudentsthroughouttheschoolday[34].Afterobserving physicalactivityacrosstwenty-fourmiddleschoolsinSan Diego,theydeterminedthatphysicalamenities,suchas areatype,areasize,andpermanentimprovements(such asbasketballcourtsandfootballgoals)wereassociated withincreasedphysicalactivityamongbothboysand girls.Theauthorsconcludethat ifwebuildit,theywill come [34];thatschooldesignandrenovationefforts mayimprovephysicalactivityamongchildren.LearningLandscapesALearningLandscape(LL)isanoveltypeofschoolyard thatoffersadiversityofelem entslackingintraditional schoolyards.Suchelementsincludeschoolyardgateways, shadestructures,banners,gardens,publicart,student art,andarttileprojects.LLsaredesignedandbuiltbya non-profitpartnershipbetweentheUniversityofColoradoDenver sCollegeofArchitectureandPlanningand alocal,urbanschooldistrict.Sinceitsinception,LLs hasattractedtheinvolvementof8,000community volunteers,18,000students ,250,000communitymembers,250Americorpsvolunteers,and20volunteerorganizations.Theinitiativehasraised47milliondollarsfor thecompletionof82newLLschoolyardsites. Aftersixyearsofcollaborationbetweenparents,elementaryschoolstudents,sta ff,faculty,neighbors,local businessesandlandscapearchitecturegraduatestudents, thefirstschoolyardwascompletedin1998.Although theprojectmerelyconstructedredesignedschoolyards initially,ithassinceevolvedintoacity-wideinitiative thatredefinestraditionalschoolgroundsandopens themupforcommunityuseoutsideofschoolhours.LL projectsfulfilledafundamentalgoaloflandscapearchitecture: toengageinscholarlyactivitiesthatstrikea balancebetweentraditiona lacademicandprofessional endeavors,whileatthesametimestretchingtheboundariesoflandscapearchitecturedesign [35]. TheLLInitiativehastransformed82neglectedDenver elementaryschoolschoolyardsintoattractiveandsafe multi-useschoolyardsthataretailoredtotheneedsand desiresofthelocalcommunity.Thisprogramhasbeen sponsoredbyabroad-based,public-privatepartnership andisdirectedbyexpertfacultyandmasters-levelstudentsfromtheDepartmentofLandscapeArchitecture attheUniversityofColoradoatDenver.In2000,Brink s UCDenverProgrampartneredwithalocalschool districtandprivatefoundationstoraisefundstoconstruct22inner-cityschool yards.Sincethattime,local bondshavebeenpassedtosecurefundingforadditional LLsforatotalof98bytheendof2012. SuccessofLLshastraditionallybeenevaluated throughacollaborativeeffortbetweenLLs,theschool district,students,community leaders,andcityofficials, usingpre-andpost-constructionsurveysandfocus groups.Theextentofthisprogramproducesavaluable opportunitytoassesstheimpactsofschoolyardrenovationonchildren sphysicalactivitypatterns.Thegoalof thisstudyistoinvestigatetheeffectoftheseschoolyard renovationsinlow-incomeurbanareasonphysical activityamongchildrenbycomparingutilizationofLL schoolyardswithmatchedcontrolschoolyards.Specifically,wewishtoconsider1)whetherLLschoolyardsare utilizedmorethannon-LLschoolyardsand2)whether childrenutilizingLLschoolyardsaremorelikelytoexhibitmoderate-tovigorousphysicalactivitybehaviour.A secondaryobjectiveistoevaluatewhethertherecency ofschoolyardrenovationhasanimpactonutilization andphysicalactivity.MethodsOwingtothefactthatthelocalschooldistrictselected whichschoolsparticipatedintheLLprogram,randomizationwasnotpossible.ConstructedLLswerematched withschoolspossessingrecent ly-builtLLs(constructed withinthepastyear),aswellascontrolsiteslacking schoolyardrenovation.Caseselectioncriteriaincluded thepercentageofstudentsreceivingfreeorreduced lunch,students raceandethnicity,andschoolsize, basedonthetotalnumberofstudentsenrolledinthe school(table1).Afterpermissionwasobtainedfromthe schooldistrict,principle sofcandidateschoolswere approachedandpermissionwasrequestedtoconduct thestudyontheirgrounds.Alltheschoolsthatwere approachedagreedtoparticipateinthestudy.Thestudy wasapprovedbytheColorado MultipleInstitutional ReviewBoard. BecauseinclusionintheLLprogramwasinitiallyprovidedforlow-incomeschools,theschoolseligibleforthis studywerelocatedindeprivedneighborhoods,populated largelybyethnicminorities.Studyschoolsaretherefore locatedinDenverneighborhoodsfacingsignificantsocial, economic,andeducationalchallenges.Studysiteswere chosenfromthreedifferentlocationsinDenver.GroupA schoolsarefromapredominatelyAfrican-American neighborhoodscharacterizedbysignificantgangactivity. GroupBandCschoolsareinneighborhoodslocated betweenthreeandfivemilesfromdowntownDenverand arecomprisedofpoor,predominatelyLatinoneighbourhoods.SchoolsingroupsBandCaresimilarwithrespect toincomeandethnicity,butaredistinguishedbyschoolAnthamatten etal InternationalJournalofBehavioralNutritionandPhysicalActivity 2011, 8 :27 http://www.ijbnpa.org/content/8/1/27 Page3of9

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size(groupBschoolshaveanaverageattendanceof559 andgroupCschoolsanaverageattendanceof395).These groupswereformedinordertoselectadequatecontrols onthebasisofincome,ethnicity,andschoolsize.Eachof thegroupscontainsoneschoolthathadLLconstruction withinayearbeforethedatawerecollected,oneschool witholderLLconstruction(constructedtwoormore yearspriortothenewly-renovatedschoolyards)andone schoolwithoutrenovatedschoolgrounds(i.e.,withnoLL construction).Childrenobservedinthisstudywereelementaryschoolstudents,betweensixandelevenyearsold. ChildrenwereobservedusingtheSystemforObservingPlayandLeisureActivityinYouth(SOPLAY). SOPLAYisaquantitativemethodforevaluatinglevels ofphysicalactivityofindividualsandassociatedenvironmentalcharacteristicsinplayandleisureenvironment [36].Targetareasarepredeterminedanddefinedas locationslikelytoprovideopportunitiesforstudentsto bephysicallyactive [37]inwhichobserversrecordthe numberofindividualspresent,theiractivitylevels,and theirgender.Eachschoolyardwasdividedintoactivity zonesthatexpressedthegroundplaneconditionand thetypeofactivityoccurring.Theobservationprotocol requirestheidentificationofschoolyardvariableswith thegreatestimpactonchildren sphysicalactivitybased onareatype,size,andpermanentimprovements.ObserversweretrainedinSOPLAYobservationmethodology byacertifiedSOPLAYinstructor.Childrenwhoare observedtobesedentaryorwalkingarenotconsidered tobephysicallyactiveandchildrenwhoareobserved engaginginvigorousphysicalactivityorina primary activity suchasusingtheschoolyardequipmentsuch asaswingorjunglegym,areconsideredtobephysically active.Whiletheobserversareabletodistinguish betweenchildrenandadults,theywerenotableto accountfortheageofspecificchildren. Observationswereconductedoverfourdaysateach schooltoobtainaccuratemeasurements.Twoobserverssimultaneouslyobservedtheactivityareafor20% ofthetotaldatacollectiontimetotestthereliability ofthedata,resultinginareliabilityestimateof87%. Observerswerenotpartoftheresearchteamto ensureaccuracyofthedatacollected.Datawerecollectedfromschoolyardsatparticipatingelementary schoolsinDenverbetweenSeptember19andOctober 29,2005andbetweenSeptember29andOctober19, 2006atregulartimeperiodsbeforethebeginningof school,duringschoolrecess, aftertheschoolfinished, andduringtheweekends.Becausetheobservations coveredtheentireschoolyards,totalschoolyarduse andthenumberofchildrenontheschoolyardatany particularobservationpoin tcouldbeestimatedfrom thesesurveys.Observationalscanscapturingactivity ontheentireschoolyardweretreatedastheunitof analysis.Between28and30schoolyardobservations wereconductedateachsite.StudyDesignWhileutilizationoftheschoolyardsismoreorless mandatoryforthechildrenduringschoolrecess,childrenmayoptionallyusetheschoolyardfacilitiesbefore orafterschooloronweekends.Itishypothesizedthat bybuildinginnovative,culturally-sensitiveschoolyard facilities,morechildrenwillbeattractedtousingthe schoolyardfacilities,particularlyduringtheseoptional periods.Inordertoaddressthisquestion,thenumber ofchildrenobservedutilizin gtheschoolyardsbefore school,duringlunchrecess, afterschool,andonweekendsiscomparedacrossLLandnon-LLschoolsinttests.Additionally,thedatawerestratifiedbygenderto examinewhetherthereweregender-baseddifferencesin utilization.Inordertoaccountfortheenrollmentdifferenceswithinthestudygroups,allobservationsarestandardizedagainsttotalschoolenrollmentandfiguresare reportedasthenumberofchildrenobservedper100 childrenenrolled(childrenattendingtheschool). Althoughchildrenattendingtheschoolmayutilize schoolyards,particularlyonweekends,schoolyarduseis predominatelybychildrenfromtheschool.Becausethe intentofthisstudyistoevaluateschoolyardsasmeans ofencouragingschoolyardutilizationandphysical activityamongchildren,twodifferentoutcomemeasures arereported:1)thenumberofchildrenobservedonthe playgroundand2)thepercentageofchildrenengagedin Table1CharacteristicsofStudyandControlSchoolsEthnicity School Enrollment Free& Reduced Lunch African American LatinoAngloAsian GroupA Renovated 33694%56%41%2%1% Recently rennovated 21988%72%26%1%1% Control 27291%66%30%2%2% Total82791%65%32%2%1% GroupB Renovated 60597%-94%3%3% Recently rennovated 49296%6%88%3%2% Control 57992%-94%4%2% Total167695%2%92%3%2% GroupC Renovated 35094%2%88%8%2% Recently rennovated 38590%6%76%10%8% Control 45094%4%91%4%1% Total118593%4%85%7%3% Anthamatten etal InternationalJournalofBehavioralNutritionandPhysicalActivity 2011, 8 :27 http://www.ijbnpa.org/content/8/1/27 Page4of9

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moderatetovigorousphysicalactivity.Thefirstmeasure isintendedtoevaluatetheimpactsofLLrenovationon schoolyard utilization ,whilethesecondisintendedto estimate how schoolyardsareutilizedwithrespectto physicalactivity. Somepreviousworkhasindicatedthatrenovationof parkfeatures,suchastrails[38]andplaygrounds[28], resultsingreaterutilization.Inordertoexaminethe specificimpactsofLLs independentofwhetherconstructionoccurredrecently werepeatedthesameseries oft-tests,butcomparedLLschoolyardsbuiltwithina yearpriortothestudywiththosebuilttwoormore yearsprior,andalsoseparatelycomparedbothgroups ofLL(recentlyandnot-recentlyconstructed)schoolyardstotheunrenovatedcontrols.Stratifyingthesites thiswayallowedustoevaluatewhetherutilizationis associatedwiththerecencyofconstruction,ifdifferencespersistamongolderLLschoolyards,orperhapsif observeddifferencesaredueinsteadtosomecombinationofthetwofactors.Duetotheevengreaterlossof statisticalpowerresultingfromadditionalstratification, schoolsarenotstratifiedintoseparateobservationalperiodsforthisfinalanalysis.ResultsTotalschoolyardusewascomparedbetweenLLand non-LLschools(whereourassumednullhypothesisis H0: 1= 2).Whenallperiodsaretakenintoconsideration,therewassignificantlygreaterutilizationofLL schoolyards(table2).Reportedasthenumberofchildrenper100childrenenrolledattheschool,anaverage of14.5childrenwasobservedonLLschoolyardscomparedto9.8childreninnon-renovatedschoolyards.Significanceisachievedamongallcategories,exceptfor boysbeforeandafterschoolandgirlsonweekends.Differentobservationperiodsyieldedcontrastingutilization patterns.Thedisparitybetweenuseofthestudyand controlschoolyardswasparticularlylargeduringlunch recess.Whileboysgenerallydisplayedsomewhatgreater utilizationoverall,thedifferenceobservedbetweenrenovatedandunrenovatedschoolyardswassimilarforboys andgirlsacrossallperiods. Asanticipated,thegreatestdifferencesinutilization wereobservedincomparison sofrecently-constructed LLschoolswithunrenovatedschoolyards(table3). Althoughtherewereobservabledifferencesinother comparisons,theonlystatisticallysignificantdifference wasamongnumberofboysobservedwhencomparing recentwitholderLLconstruction. Wealsoreportthe percentage ofchildrenengagedin moderatetovigorousphysicalactivityasaportionof allthechildrenobserved(tables4and5).Thesedata addressadifferentquestion:whetherchildren,once theyarephysicallyonarenovatedschoolyard,aremore Table2ComparisonofallchildrenobservedonschoolyardsatLLandcontrolschoolsduringdifferentutilization periods,reportedasnumberofchildrenper100childrenenrolledintheschoolMeanusage,Learning Landscapes Meanusage,unrenovated schoolyards Mean difference Standarderror difference p Allperiods Allchildren14.59.84.61.7 **.008 Boys7.75.32.41.1 *.023 Girls6.84.52.30.8 **.008 Before School Allchildren 22.3 10.8 11.5 6.0 .066 Boys 12.7 6.4 6.3 3.7 .106 Girls 9.6 4.4 5.3 2.4 *.040 LunchRecess Allchildren 27.4 20.8 6.6 2.4 **.007 Boys 14.4 10.9 2.8 1.3 **.007 Girls 13.0 9.9 3.1 1.3 *.016 AfterSchool Allchildren 4.2 2.1 2.1 0.8 *.007 Boys 2.0 1.2 0.8 0.4 .065 Girls 2.2 0.8 1.3 0.3 **.001 Weekends Allchildren 0.8 0.2 0.6 0.3 *.068 Boys 0.5 0.1 0.4 0.2 *.025 Girls 0.2 0.1 0.2 0.1 .083*p<.05**p<.01.Anthamatten etal InternationalJournalofBehavioralNutritionandPhysicalActivity 2011, 8 :27 http://www.ijbnpa.org/content/8/1/27 Page5of9

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likelytoengageinphysicalactivitythanonunrenovatedsites.Therewerenostatisticallysignificantdifferencesobservedbetweenrenovatedandunrenovated schoolyardsforanyperiodforpercentageofactive children.DiscussionInlightoftheobesityepidemicanditsassociatedhealth impactsintheUS,parents,educators,andhealth researchersstrivetodiscoverwhichenvironmentalinterventionsencouragephysicalactivityamongchildren. Amongthewaysthatdesignstrategiescancontributeto addressingthisproblem,schoolyardscanbeconstructed toencouragechildrentospendtimeoutdoorsandto activelyutilizeschoolyards.Evidence-basedevaluationof thebehavioralimpactsofspecificdesigninitiativesisparticularlyimportantinacontextinwhichfundingis scarce.Suchevidenceisoften notavailableoraccessible toprivate-andpublic-sectorpolicymakers[39]. Whileurbandesignershavediscussedhowspecific designsofchildren sspacesmightencouragehealthy behavior,fewstudieshaveevaluatedtheeffectivenessof thesedesignsoncetheyhavebeenimplemented.Outsideofsomeevidencethattheadditionofcoloris relatedtoincreasedutilization[32,40],littlework addressestheimpactsofspecificdesignplans,eitherin termsofparticularschoolyardcomponentsorasa broaderdesignstrategy.Withthenotableexceptionofa studyfromCleveland[28],therehasbeenlittleprevious workontheimpactsofrenovationonschoolyardutilization.LLisaprogramwhichplaceshigh-quality recreationalspacesintopub licschoolsservingDenver, includingthosewithlow-incomepopulations.Itwas observedthatLLschoolyardsexperiencedsignificantly greaterutilizationforallobservationperiodsoverunrenovatedspaces.When optional periods(beforeschool, afterschool,andonweekends)areconsideredinisolation,greaterutilizationwasgenerallyobservedforboth boysandgirls,withafewexceptionsnotedinthe results. Thereisevidencethatboysaremorelikelythangirls toexhibitgreaterutilizationandmorevigorousphysical activityinbothschoolyardsingeneral[40]andonrenovatedplaygroundsinparticular[28].Whileitremains unclearatwhatageweight-relateddifferencesinphysicalactivityareapparentingirls[41],itiswidely acceptedthatphysicalactivityleadstobenefitsinphysicalhealthaswellassocialdevelopment[42,43].Inthis Table3Differencesinschoolyardutilizationby constructionstatusforallperiods,reportedinnumberof childrenobservedpernumberofchildrenper100 childrenenrolledintheschoolOldLLvs. Control NewLLvs. Control NewLLvs. OldLL mean difference pmean difference pmean difference p All Children 2.4.1947.0**.0034.6.056 Boys 0.8.4164.1**.0033.3*.014 Girls 1.7.0872.9**.0061.2.264*p<.05**p<.01. Table4Comparisonofrateofmoderatelytophysically activechildrenobservedonschoolyardsatLLand controlschoolsduringdifferentutilizationperiods, reportedaspercentageMeanrate, Learning Landscapes Meanrate, unrenovated schoolyards Mean difference Standard error difference p All periods All children 42.240.41.73.3.602 Boys44.242.51.73.8.646 Girls39.738.51.23.3.114 Before School All children 27.135.8-8.64.1.050 Boys29.733.9-4.26.0.491 Girls26.240.4-14.19.8.174 Lunch Recess All children 42.843.5-0.72.6.796 Boys46.545.70.73.2.841 Girls38.740.1-2.32.7.402 After School All children 47.336.710.69.0.242 Boys48.040.66.310.5.550 Girls48.033.514.58.9.111 Weekends All children 42.941.01.932.0.956 Boys44.242.91.331.4.969 Girls43.316.626.757.2.665 Table5Differencesinrateofmoderatelytophysically activechildrenobservedforallperiods,reportedasa percentOldLLvs. control NewLLvs. control NewLLvs. oldLL mean difference pmean difference pmean difference p All Children 0.3.9933.2.4133.2.409 Boys -0.4.9283.7.4034.1.341 Girls 1.1.7631.2.7760.7.987 Anthamatten etal InternationalJournalofBehavioralNutritionandPhysicalActivity 2011, 8 :27 http://www.ijbnpa.org/content/8/1/27 Page6of9

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study,greaterutilizationbygirlswasobservedonLL sitesbeforeandafterschoolandduringlunchrecess, butnotonweekends.Thereasonsbehindthesefindings meritadditionalscrutinyonseverallevels.Furtheranalysismightreveal,forexample,thatspecificfeaturesof theLLschoolyardsencouragegirlstousethesitesinan activemanner.Schoolyardusewasgenerallymuch higherbeforeschoolthanitwasafterschool.Itseems plausiblethatgirlsinparticulararemorelikelytoutilize thesespacesbeforeandafterschool,incontrastto weekends,asaconsequenceoftheirfamily sperceived safetyofhavingotherchildrenandschoolstaffpresent. Low-incomeschooldistrictsthatwishtoimplement extra-curricularprogramsto improvephysicalactivity amongtheirstudents,andamonggirlsinparticular, mightbenefitfromresearchfocusedaroundthisquestion.Futureworkmightalsoinvestigatehowageaffects girls utilizationpatterns. Inordertoaddressthequestionofhowrenovation affectedchildren slikelihoodtoengageinphysicalactivity,wealsoexaminedthepercentageofchildrenwho weremoderatelyorvigorouslyactiveasaproportionof allchildrenobservedontheschoolyards.Thismeasureis intendedtoestimatethewaythataparticularspaceinfluencesthetypeofactivitythatchildrenengagein;some playspacesmightcontainfeaturesthatencouragechildrentoparticipateinspecificactivitiesthatareconducive tovigorousphysicalactivity,forexample.Nostatistically significantdifferenceswereobservedinthismeasure betweenanyofthecomparisongroups.Itseemsplausible thattherearedifferencesinho wchildrenutilizespecific componentsofvariousplayspaces,butthismaynotbe observableatthescaleofanentireschoolyard.Aschoolyardzonecontainingslides,forexample,mayencourage moreorlessactivitythananotherzonecontainingajunglegym.Worktocompareactivityacrossschoolyard zonesthatcontaindifferentfeaturesmightbeafruitful avenueforadditionalinquiry. Anadditionalfeatureofthisresearchisthemeasurementoftheimpactsoftherecencyofschoolyardconstruction.UtilizationofLLschoolyardsconstructed withinthepreviousyearwascomparedwithschoolyards constructedbetweenthreeandfouryearspriortothe studyperiod.Greateruti lizationwasobservedonLL sitesthatnewerthanoneyearthanontheolderLL sites,butthedifferenceswerenotstatisticallysignificant, withtheexceptionoftheutilizationmeasuresamong boys.Ifthedifferencesobservedinthisworkandevidencefromotherstudies,suchasColabianchietal. s [28],areseentoprovideevidencethatschoolyardconstructionresultsingreaterutilizationandactivity, schoolyardrenovationitse lfmaybeavalidplanning strategyforincreasingutilization.Additionalstudyis requiredtodeterminethedurationoftheimpactsof renovationandwhetherthesedifferencesaretheconsequenceofparticularcomponentsoftherenovated schoolyards.StudyLimitationsWhilewebelievethatthisworkprovidesevidenceofthe impactsofschoolyardrenovation,thisstudywas designedasacase-controlstudy,introducingthepotentialforconfoundingbyunobservedorunconsidered thirdvariables.Akeyquestioninstudyinstudyofphysicalactivityandurbanenvironmentsishowtoimplementchangesthatresultinsustainedchangesin physicalactivitypatterns.Thisworkprovidesevidence thatrenovationofschoolyardsresultsinanincreasein physicalactivity,butitisnotclearforhowlongthis effectlasts.Theevidencefromthisworkalsodoesnot shedlightonspecificstrategiesforimplementingsustainedchangeinactivity,akeyfocusforphysicalactivity researchandpolicy. Itmightbepossiblethatrenovationonlybenefitschildrenwhoareactivetobeginwith,butwholacksuitable facilitiestopracticephysicalactivityinthedeprived neighbourhoodsexaminedhere.Whileitisworthwhile toinvestigatestrategiesthatreducegeographicand socioeconomicdisparitiesinphysicalactivitypatterns,a keyfuturegoalistouncoverspecificdesignstrategiesto encouragegreateroveralluseamongallchildren.Similarly,itwouldalsobeworthwhiletoinvestigatespecific designmechanismsresponsibleforincreaseduse.AdditionalstudyofLLispresentlyconsideringthese researchquestionsinalongitudinalstudydesign.While thisstudywasoriginallydesignedtoassessandcompare utilizationofLLandnon-LLschoolyards,stratification intogenderandtimeperiodresultedinalossofstatisticalpower.Withadditionaldata,theseandothervariablescanbeanalyzedwithgreaterstatisticalcertainty. ItispossiblethatLLsitesattractedgreateruseon accountoftheirrelativelyrecentdateofconstruction, orperhapssomeotherfactorassociatedtherewith(such asgeneralcleanliness,thestateoftheequipment,orthe attentionthatwasbroughttotheschoolyardbycommunityinvolvementwiththeconstructioneffortsandthe associatedpublicity).AdditionalworkcomparingLL sitestootherrenovatedschoolyardsthatwerenotconstructedthroughtheprogramisnecessarytothread apartwhichofthesefactorsisimportant.Finally,while statisticallysignificantdifferenceswereobserved,results wereattenuatedbythefactthattherewereonly264 observationscansacrossnin eschools.Theincorporationofmoredatawouldenabletheexaminationof finer-scaledistinctionsbetweenschoolyarduseatdifferentkindsofsites,andcouldenablemoresophisticated analysis,by,forexample,usingalogisticregressionanalysistomodeltheimpactsofparticularsitefeatures.Anthamatten etal InternationalJournalofBehavioralNutritionandPhysicalActivity 2011, 8 :27 http://www.ijbnpa.org/content/8/1/27 Page7of9

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ConclusionsWhileencouragingphysicalactivityamongchildrenis animportantpublichealthgoalthatmaybeaddressed throughacarefulplanninganddesignprocess,itis essentialthatspecificstrategiesbeexploredandevaluatedinordertodeterminehowandtowhatextent thesestrategiesencouragephysicalactivityamongchildren.ThisstudyprovidesevidencethatschoolyardrenovationfromLearningLandscapesincreasesactive utilizationbyschoolchild renduringbothmandatory andoptionalplayperiods,contributingtoanascent bodyofwork[28,44]thatsuggeststhatsuchrenovation maybeaneffectivemethodtoencouragingphysical activityamongchildren.Acknowledgements FundingforthisprojectwasprovidedbytheRobertWoodJohnson Foundation. Authordetails1DepartmentofGeographyandEnvironmentalSciences,Universityof ColoradoDenver,Denver,CO,USA.2DepartmentofLandscapeArchitecture, UniversityofColoradoDenver,Denver,CO,USA.3ColoradoCenterfor CommunityDevelopment,CollegeofArchitectureandPlanning,University ofColoradoDenver,Denver,CO,USA.4AdamsCountyYouthInitiative, Denver,CO,USA.5DepartmentofPublicHealthSciences,Universityof HawaiiatManoa,Honolulu,HI,USA. Authors contributions BK,LB,andCNdesignedthestudy,obtainedfundingfor,andmanagedthe SOLPLAYdatacollectionprocess.PA,LB,SL,EG,andBKcontributedtothe finalversionofthemanuscript.PAandEGpreparedthedataforanalysis.PA devisedthecurrentanalysis,analyzedthedata,andproducedtheinitial draftofthemanuscript.Allauthorsreadandapprovedthefinalmanuscript. Competinginterests Theauthorsdeclarethattheyhavenocompetinginterests. Received:5August2010Accepted:9April2011Published:9April2011 References1.JamesWPT: WHOrecognitionoftheglobalobesityepidemic. 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