简介：Chronicdiseaseshavebecomeafocalpointofpublichealthworldwidewithestimatesoftrillionsofdollarsinannualhealthcarecostandcausingmorethan36milliondeathsayear.Lifestylefactorssuchasphysicalinactivityareheavilycorrelatedwiththedevelopmentofmanychronicdiseases.Newstrategiesforprimaryandsecondarydiseasepreventionaredesperatelyneededtoaidinbluntingthenegativeeconomicandsocialimpactofthesediseases.Physicalactivity(PA)andexercisearenowconsideredprincipalinterventionsforuseinprimaryandsecondarypreventionofchronicdiseases.Currently,moreemphasisinprimarypreventionofdiseaseisnecessarytoreducediseaseriskinyouthandadults;howeverwithchronicdiseaseprevalencesohigh,similaremphasisisalsonecessaryforsecondarypreventioninthosechildrenandadultsalreadyinflictedwithchronicdiseases.Conditionssuchascardiovasculardisease,type2diabetes,obesity,andcanceraredrasticallyimprovedwhenPAandexercisearepartofamedicalmanagementplan.Inaddition,thenationalPAguidelinesinconjunctionwithPApromotiontoolslikeExerciseisMedicine?areneededtopromoteincreasedPAandexerciselevelsworldwide.

简介：ThepreviousSpecialIssuewasdevotedtophysicalactivity(PA),physicalfitness,diet,andhealthinyoungpeople.ThecontentofthissecondSpecialIssuewillfocusonPAandchronicdiseaseinchildrenandyoungadults.ThefirstpaperwrittenbyDurstineetal.considerstheproblemofchronicdiseasesbecomingapublichealthconcernworldwidewithestimatesoftrillionsofdollaisinannualhealthcarecostsandcausingmorethan36milliondeathsayear.Their