【Exerciseseemstobegoodforthehumanbrainwithmanyrecentstudiessuggestingthatregularexerciseimprovesmemoryandthinkingskills.Butaninterestingnewstudyaskswhethertheapparentcognitivebenefitsfromexercisearerealor】

　　Exerciseseemstobegoodforthehumanbrainwithmanyrecentstudiessuggestingthatregularexerciseimprovesmemoryandthinkingskills.Butaninterestingnewstudyaskswhethertheapparentcognitivebenefitsfromexercisearerealorjustaplaceboeffect—thatisifwethinkwewillbe“smarter”afterexercisedoourbrainsrespondaccordingly?Theanswerhassignificantimplicationsforanyofushopingtouseexercisetokeepourmindssharpthroughoutourlives.

　　Whilemanystudiessuggestthatexercisemayhavecognitivebenefitsrecentlysomescientistshavebeguntoquestionwhethertheapparentlybeneficialeffectsofexerciseonthinkingmightbeaplaceboeffect.SoresearchersatFloridaStateUniversityinTallahasseeandtheUniversityofIllinoisatUrbana-Champaigndecidedtofocusonexpectationsonwhatpeopleanticipatethatexercisewilldoforthinking.Ifpeople’sexpectationsjibe(吻合)closelywiththeactualbenefitsthenatleastsomeofthoseimprovementsareprobablyaresultoftheplaceboeffectandnotofexercise.

　　ForthenewstudywhichwaspublishedlastmonthinPLOSOnetheresearchersrecruited171peoplethroughanonlinesurveysystemtheyaskedhalfofthesevolunteerstoestimatebyhowmuchastretchingandtoningregimens(拉伸运动)performedthreetimesaweekmightimprovevariousmeasuresofthinking.Theothervolunteerswereaskedthesamequestionsbutaboutaregularwalkingprogram.

　　Inactualexperimentsstretchingandtoningprogramgenerallyhavelittleifanyimpactonpeople’scognitiveskills.Walkingontheotherhandseemstosubstantiallyimprovethinkingability.

　　Butthesurveyrespondentsbelievedtheoppositeestimatingthatthestretchingandtoningprogramwouldbemorebeneficialforthemindthanwalking.Theestimatesofbenefitsfromwalkingwerelower.

　　Thesedatawhiletheydonotinvolveanyactualexercisearegoodnewsforpeoplewhodoexercise.“Theresultsfromourstudysuggestthatthebenefitsofaerobicexercisearenotaplaceboeffect”saidCaryStothartagraduatestudentincognitivepsychologyatFloridaStateUniversitywholedthestudy.

　　IfexpectationshadbeendrivingtheimprovementsincognitionseeninstudiesafterexerciseMr.Stothartsaidthenpeopleshouldhaveexpe