Areyoupreparingforabigtest?Ifs-查字典问答网

来自刘永文的问题

　　Areyoupreparingforabigtest?Ifsoyoumaywanttogoplaysomebasketballinbetweenhittingthebooks.Doctorsarestartingtofindmoreandmoreinformationthatsuggestsaconnectionbetweenexerciseandbraindevelopment.JudyCameronascientistatOregonHealthandScienceUniversitystudiesbraindevelopment.Accordingtoherresearchitseemsthatexercisecanmakebloodvessels（管）includingthoseinthebrainstrongerandmorefullydeveloped.Dr.Cameronclaimsthisallowspeoplewhoexercisetoconcentratebetter.Asshesays"Whilewealreadyknowthatexerciseisgoodfortheheartexercisecanreallycausephysicalchangesinthebrain."

　　Theeffectsofexerciseonbraindevelopmentcanevenbeseeninbabies.Babieswhodoactivitiesthatrequirealotofmovementandphysicalactivityshowgreaterbraindevelopmentthanbabieswhoarelessphysicallyactive.Withbabiesevenalittlemovementcanshowbigresults.MargaretBarnesapediatrician（儿科医生）believesintheimportanceofexercise.Shethinksthatmanylearningdisabilitiesthatchildrenhaveinelementaryschoolorhighschoolcanbetracedbackto（可追溯到）alackofmovementasbabies."Babiesneedmovementthatstimulatestheirfivesenses（感官）.Theyneedtoestablishaconnectionbetweenmotion（动作）andmemory.Inthiswayastheygetolderchildrenwillbegintoassociate（联系）physicalactivitywithhigherlearning"saysMargaret.

　　Olderpeoplecanbeefup（加强）theirbrainsaswell.ColumbiaUniversitystudiedagroupofseniorsranginginagefrom（从...排列到）seventytoseventy-nine.Theirstudyshowedashort-termmemoryincreaseofupto40percentafterexercisingjustthreehoursaweek.Theexercisedoesnothavetobeverydifficultbutitdoeshavetoincreasetheheartrate.Alsojustlikethemotionforinfants（婴儿）exerciseforolderpeopleshouldinvolvesomecomplexity.Learningsomenewskillsormotionssuchaswithyogaortai-chihelpstoopenupmemorypathsinthebrainthatmaynothavebeenusedforalongtime.

　　Formostpeopleanytypeofphysicalactivitythatincreasestheheartrateishelpful.Themaingoalistoincreasethebrain'sflowofblood.Andyourbraincanbenefitfromaslittleastwotothreehoursofexerciseaweek.

　　1．Whatisthemainideaofthisreading?

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