题目内容：
Questionsarebasedonthefollowingpassage. Itisnosecretamongathletesthatinordertoimproveperformanceyou’vegottoworkhard.
However,hardtrainingbreaksyoudownandmakesyouweaker,itisrestthatmakesyoustronger.
Improvementonlyoccursduringtherestperiodfollowinghardtraining.Thisadaptationisaccomplishedbyimprovingefficiencyoftheheartandcertainsystemswithinthemusclecells.
Duringrecoveryperiodsthesesystemsbuildtogreaterlevelstocompensateforthestressthatyouhaveapplied.Theresultisthatyouarenowatahigherlevelofperformance.
Ifsufficientrestisnotincludedinatrainingprogram,imbalancebetweenexcesstrainingandinadequaterestwilloccur,andperformancewilldecline.The“overtrainingsyndrome（综合症）”isthenamegiventothecollectionofemotional,behavioral,andphysicalsymptomsduetoovertrainingthathaspersistedforweekstomonths.Itismarkedbycumulativeexhaustionthatpersistsevenafterrecoveryperiods.
Themostcommonsymptomisfatigue.Thismaylimitworkoutsandmaybepresentatrest.Theathletesmayalsobecomemoody,easilyimitated,havealteredsleeppatterns,becomedepressed,orlosethecompetitivedesireandenthusiasmforthesport.Somewillreportdecreasedappetiteandweightloss.Physicalsymptomsincludepersistentmuscularsoreness,increasedfrequencyofviral（病毒性的）illnesses,andincreasedincidenceofinjuries.
Thetreatmentfortheovertrainingsyndromeisrest.Thelongertheovertraininghasoccurred,themorerestrequired,therefore,earlydetectionisveryimportant.Iftheovertraininghasonlyoccurredforashortperiodoftime（e.g.3
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