Purpose:ThepurposeofthisstudywastoinvestigatetheimpactofacuteexerciseonreactiontimeandresponsepreparationduringaGo/NoGoTaskinchildrenwithattentiondeficithyperactivitydisorder(ADHD).Methods:NineteenchildrenwithADHD(agedbetween8and12yearsold)undertooka30-mininterventionthatconsistedoftreadmillrunningorvideo-watchingpresentedinacounterbalancedorderondifferentdays.AGo/NoGoTaskwasadministratedafterexerciseorvideo-watching.Results:Theresultsindicatedashorterreactiontimeandsmallercontingentnegativevariation(CNV)2amplitudefollowingexerciserelativetothevideo-watching.Foreventrelatedpotential(ERP)analyses,greaterCNV1andCNV2amplitudesinresponsetoNoGostimuliincomparisontoGostimuliwasobservedinthevideo-watchingsessiononly.Conclusion:ThesefindingssuggestthatacuteexercisemaybenefitchildrenwithADHDbydevelopingappropriateresponsepreparation,particularlyinmaintainingastablemotorpreparatorysetpriortoperformingthegiventask.