简介：Background:Animpactofregularphysicalactivity(RPA)ontheabdominalmusclesmaybesignificantwhencomparingvarioussymptomaticgroups.However,thereislackcomprehensiveinformationinthisfield.Theobjectiveofthisstudywastoassessthelateralabdominalwallatrestandduringabdominaldrawing-inmanoeuvreinadolescentphysicallyactivegirlsindifferentbodypositions.Methods:Onehundredandforty-fourfemalestudents,13–17yearsofage,participatedinthestudy.Participantsweredividedinto2groupsbasedonaphysicalactivity(PA)statement.Measurementsofthethicknessoftheabdominalmusclesatrestandduringabdominaldrawing-inmanoeuvreweremadeinthesupineandstandingpositionsbyultrasoundimaging.Results:Comparedtothecontrolgroup,activitiesoftheobliquusinternusandtransversusabdominismuscleswerehigherintheregularPAgroupby8.9%(95%CI:3.1–14.7)and36%(95%CI:19.1–47.5),respectively.IntheRPAgroup,thetransversusabdominispreferentialactivationratiowasgreaterby0.03(95%CI:0.01–0.04),andthecontractionratiowasgreaterbyameanvalueof0.35(95%CI:0.18–0.46).Conclusion:RPAdoesnothaveanyeffectontherestingthicknessoftheabdominalmusclesinthesupineandstandingpositions.GirlsperformingRPAhaveagreaterabilitytoperformanindependentactivationandgreatercontractionsofthetransversusabdominis.

简介：Purpose:Thisstudyaimedtoinvestigatewhetherworkloadintensitymodulatesexercise-inducedeffectonreactiontime(RT)performances,andmorespecificallytoclarifywhethercognitivecontrolthatplaysacrucialroleinrapiddecisionmakingisaltered.Methods:FourteenparticipantsperformedaSimonTaskwhilecycling20minatalight(firstventilatorythreshold,VT1e20%),moderate(VT1),orveryhard(VT1t20%)levelofexercise.Results:After15minofcycling,RTsarefasterthanduringthefirst5minofexercise.ThisbenefitdoesnotfluctuatewiththeintensityofexerciseandenlargesasRTlengthens.Despiteanumericaldifferencesuggestingagreaterfacilitationduringmoderateexercise(16ms)thanduringalightexercise(10ms),thebenefitisnotstatisticallydifferent.Interestingly,wedidnotobserveanysignsofworseningonRToronaccuracyduringveryhardexercise.Conclusion:Cognitivecontrolisextremelyrobustandappearsnottobeaffectedbytheintensityofexercise.Theselectiveinhibitionandthebetween-trialsadjustmentsareeffectivefromthebeginningtotheendofexercise,regardlessoftheworkloadoutput.

简介：Clinicaldisordersoftenarecharacterizedbyabreakdownindynamicalprocessesthatcontributetothecontrolofuprightstanding.Disruptiontoalargenumberofphysiologicalprocessesoperatingatdifferenttimescalescanleadtoalterationsinposturalcenterofpressure(CoP)fluctuations.Multiscaleentropy(MSE)hasbeenusedtoidentifydifferencesinfluctuationsofposturalCoPtimeseriesbetweengroupswithandwithoutknownphysiologicalimpairmentsatmultipletimescales.Thepurposeofthispaperisto:1)reviewbasicelementsandcurrentdevelopmentsinentropytechniquesusedtoassessphysiologicalcomplexity;and2)identifyhowMSEcanprovideinsightsintothecomplexityofphysiologicalsystemsoperatingatmultipletimescalesthatunderliethecontrolofposture.WereviewandsynthesizeevidencefromtheliteratureprovidingsupportforMSEasavaluabletooltoevaluatethebreakdowninthephysiologicalprocessesthataccompanychangesduetoaginganddiseaseinposturalcontrol.ThisevidenceemergesfromobservedlowerMSEvaluesinindividualswithmultiplesclerosis,idiopathicscoliosis,andinolderindividualswithsensoryimpairments.Finally,wesuggestsomefutureapplicationsofMSEthatwillallowforfurtherinsightintohowphysiologicaldeficitsimpactthecomplexityofposturalfluctuations;thisinformationmayimprovethedevelopmentandevaluationofnewtherapeuticinterventions.

简介：Background:Infraredthermographicimaging(IRTG)isasafeandreliabletechnologyusedtomonitorskintemperature.ThemainaimofourstudywastoevaluatetherelationshipbetweenskintemperaturechangesandmusclefatigueinordertoanswerthemainresearchquestionifIRTGcanbeusedtomonitormusclefatigue.Methods:Thiswasacasestudyperformedona23-year-oldtrainedmiddledistancerunner.Afterwarm-upthesubjectwasexercisingonthedynamometerfor7.5minat120?/sperformingonlyconcentriccontractionsofquadriceps.AtthesametimeIRTGrecordingofboth(exercisingandnon-exercising)quadricepswasperformed.Results:Acorrelationalanalysisthatwasperformedinordertoquantifytherelationshipbetweenpowerandtemperaturechangeovertimehasshownthatthereisasignificantnegativecorrelationbetweenskintemperatureincreaseandpowerdecrease(r=-0.543,p=0.036)ofexercisingquadriceps.Inlinearregressionmodeltheexercisingquadricepspowercouldbepredictedfromskintemperature.Nosuchrelationshipswerenotedforthenon-exercisinglimbthatservedasacontrol.Conclusion:Webelievethatcorrelationbetweenskintemperaturechangeandmusclepoweroutputasdescribedinthiscasestudydeservesfurtheranalysisonthelargersampleincludingsubjectsofthedifferentages,healthstatus,andphysicalabilitiesinordertocreateanewtoolformonitoringthemusclefatigue.

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简介：Concussion,ormildtraumaticbraininjury,incidencerateshavereachedepidemiclevelsandimpairedposturalcontrolisacardinalsymptom.Thepurposeofthisreviewistoprovideanoverviewofthelinearandnon-linearassessmentsofpost-concussionposturalcontrol.Thecurrentacuteevaluationforconcussionutilizesthesubjectivebalanceerrorscoringsystem(BESS)toassessposturalcontrol.Whilethesensitivityoftheoveralltestbatteryishigh,thesensitivityoftheBESSisunacceptablylowand,withrepeatadministration,isunabletoaccuratelyidentifyrecovery.Sophisticatedmeasuresofposturalcontrol,utilizingtraditionallinearassessments,haveidentifiedimpairmentsinposturalcontrolwellbeyondBESSrecovery.Bothassessmentsofquietstanceandgaithaveidentifiedlingeringimpairmentsforatleast1monthpost-concussion.Recently,theapplicationofnon-linearmetricstoconcussionrecoveryhavebeguntoreceivelimitedattentionwiththemostcommonlyutilizedmetricbeingapproximateentropy(ApEn).ApEn,mostcommonlyinthemedial-lateralplane,hassuccessfullyidentifiedimpairedposturalcontrolintheacutepost-concussiontimeframeevenwhenlinearassessmentsofinstrumentedmeasuresareequivalenttohealthypre-injuryvalues;unfortunatelythesestudieshavenotgonebeyondtheacutephaseofrecovery.Onestudyhasidentifiedlingeringdeficitsinposturalcontrol,utilizingShannonandRenyientropymetrics,whichpersistatleastthroughclinicalrecoveryandreturntoparticipation.Finally,limitedevidencefromtwostudiessuggestthatindividualswithaprevioushistoryofasingleconcussion,evenmonthsoryearsprior,maydisplayalteredApEnmetrics.Overall,non-linearmetricsprovideafertileareaforfuturestudytofurthertheunderstandingofposturalcontrolimpairmentsacutelypost-concussionandaddressthecurrentchallengeofsensitiveidentificationofrecovery.

简介：Background:Marginalchangesintheexecutionofcompetitivesportsmovementscanrepresentasignificantchangeforperformancesuccess.However,suchdifferencesmayemergeonlyatcertainexecutionintensitiesandarenoteasilydetectablethroughconventionalbiomechanicaltechniques.Thisstudyaimedtoinvestigateifandhowcompetitionstandardandprogressionspeedaffectracewalkingkinematicsfrombothaconventionalandacoordinationvariabilityperspective.Methods:Fifteenexperiencedathletesdividedintothreegroups(elite,international,andnational)werestudiedwhileracewalkingonatreadmillattwodifferentspeeds(12.0and15.5km/h).Basicgaitparameters,theangulardisplacementofthepelvisandlowerlimbs,andthevariabilityincontinuousrelativephasebetweensixdifferentjointcouplingswereanalyzed.Results:Mostofthespatio-temporal,kinematic,andcoordinationvariabilitymeasuresprovedsensitivetothechangeinspeed.Conversely,non-lineardynamicsmeasureshighlighteddifferencesbetweenathletesofdifferentcompetitionstandardwhenconventionalanalyticaltoolswerenotabletodiscriminatebetweendifferentskilllevels.Continuousrelativephasevariabilitywashigherfornationallevelathletesthaninternationalandeliteintwocouplings(pelvisobliquity—hipflex/extensionandpelvisrotation—ankledorsi/plantarflexion)andgaitphases(earlystanceforthefirstcoupling,propulsivephaseforthesecond)thataredeemedfundamentalforcorrecttechniqueandperformance.Conclusion:Measuresofcoordinationvariabilityshowedtobeamoresensitivetoolforthefinedetectionofskill-dependentfactorsincompetitiveracewalking,andshowedgoodpotentialforbeingintegratedintheassessmentandmonitoringofsportsmotorabilities.

简介：Neuromuscularactivityissuppressedduringmaximaleccentric（ECC）musclecontractioninuntrainedsubjectsowingtoattenuatedlevelsofcentralactivationandreducedspinalmotorneuron（MN）excitabilityindicatedbyreducedelectromyographysignalamplitude,diminishedevokedH-reflexresponses,increasedautogenicMNinhibition,anddecreasedexcitabilityindescendingcorticospinalmotorpathways.MaximumECCmuscleforcerecordedduringmaximalvoluntarycontractioncanbeincreasedbysuperimposedelectricalmusclestimulationonlyinuntrainedindividualsandnotintrainedstrengthathletes,indicatingthatthesuppressioninMNactivationismodifiablebyresistancetraining.Insupportofthisnotion,maximumECCmusclestrengthcanbeincreasedbyuseofheavy-loadresistancetrainingowingtoaremovedordiminishedsuppressioninneuromuscularactivity.Prolonged（weekstomonths）ofheavy-loadresistancetrainingresultsinincreasedH-reflexandV-waveresponsesduringmaximalECCmuscleactionsalongwithmarkedgainsinmaximalECCmusclestrength,indicatingincreasedexcitabilityofspinalMNs,decreasedpresynapticand/orpostsynapticMNinhibition,andelevateddescendingmotordrive.Notably,theuseofsupramaximalECCresistancetrainingcanleadtoselectivelyelevatedV-waveresponsesduringmaximalECCcontraction,demonstratingthatadaptivechangesinspinalcircuitryfunctionand/orgainsindescendingmotordrivecanbeachievedduringmaximalECCcontractioninresponsetoheavy-loadresistancetraining.

简介：Sincethe1960's,hundredsofarticleshavebeenpublishedontheeffectsofexerciseoncognitionandmorerecentlyonexecutivefunctions.Alargevarietyofeffectshavebeenobserved:acuteorlong-lasting,facilitatingordebilitating.Severaltheoreticalframeworkshavebeenproposedtoexplaintheseeffectswithplausiblemechanisms.However,asyetnoneofthesemodelshassucceededinunifyingalltheobservationsinasingleframeworkthatsubsumesalleffects.Theaimofthepresentreviewistorevisitthestrengthmodelofself-controlinitiatedbyBaumeisterandhiscolleaguesinthe1990'sinordertoextenditsassumptionstoexercisepsychology.Thismodelprovidesaheuristicframeworkthatcanexplainandpredicttheeffectsofacuteandchronicexerciseoneffortfultaskstappingself-regulationorexecutivefunctions.Areconsiderationofexerciseasaself-controltaskresultsfromthisperspective.Anewavenueforfutureresearchisdelineatedbesidesmoretraditionalapproaches.

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简介：WiththeRioOlympicsjustafewmonthspast,weremembertheexcitement,theincredibleperformances,andthecontroversies.Ashappenssooften,theOlympicGamesfocusattentionnotonlyonathleticachievementsbutalsoonhowathletesmayreachever-increasinglevelsofperformance.Doping,medicaldoping

简介：Background:Activevideogames(AVGs)encouragewholebodymovementstointeractorcontrolthegamingsystem,allowingtheopportunityforskilldevelopment.Childrenwithautismspectrumdisorder(ASD)showdecreasedfundamentalmovementskillsincomparisonwiththeirtypicallydeveloping(TD)peersandmightbenefitfromthisapproach.ThispilotstudyinvestigateswhetherplayingsportsAVGscanincreasetheactualandperceivedobjectcontrol(OC)skillsof11childrenwithASDaged6–10yearsincomparisonto19TDchildrenofasimilarage.Feasibilitywasasecondaryaim.Methods:Actual(TestofGrossMotorDevelopment)andperceivedOCskills(PictorialScaleofPerceivedMovementSkillCompetenceforYoungChildren)wereassessedbeforeandaftertheintervention(6×45min).Results:Actualskillscoreswerenotimprovedineithergroup.TheASDgroupimprovedinperceivedskill.Allchildrencompletedtherequireddoseandparentsreportedtheinterventionwasfeasible.Conclusion:TheuseofAVGsasaplay-basedinterventionmaynotprovideenoughopportunityforchildrentoperformthecorrectmovementpatternstoinfluenceskill.However,playofsuchgamesmayinfluenceperceptionsofskillabilityinchildrenwithASD,whichcouldimprovemotivationtoparticipateinphysicalactivities.

简介：Background:Athleteshavebeenshowntoexhibitbetterbalancecomparedtonon-athletes(NON).However,fewstudieshaveinvestigatedhowthesurfaceonwhichathletestrainaffectsthestrategiesadoptedtomaintainbalance.Twodistinctathletegroupswhoexperiencedifferenttypesofsport-specificbalancetrainingarestablesurfaceathletes(SSA)suchasbasketballplayersandthosewhotrainonunstablesurfaces(USA)suchassurfers.ThepurposeofthisstudywastoinvestigatetheeffectsoftrainingsurfaceondynamicbalanceinathletescomparedtoNON.Methods:EightNON,eightSSA,andeightUSAperformedfive20-strialsineachoffiveexperimentalconditionsincludingastaticconditionandfourdynamicconditionsinwhichthesupportsurfacetranslatedintheanteroposterior(AP)ormediolateral(ML)planesusingpositiveornegativefeedbackparadigms.Approximateentropy(ApEn)androotmeansquaredistance(RMS)ofthecenterofpressure(CoP)werecalculatedfortheAPandMLdirections.Four3×5(group×condition)repeatedmeasuresANOVAswereusedtodeterminesignificanteffectsofgroupandconditiononvariablesofinterest.Results:USAexhibitedsmallerApEnvaluesthanSSAintheAPsignalswhilenosignificantdifferenceswereobservedintheMLCoPsignals.Generally,thenegativefeedbackconditionswereassociatedwithsignificantlygreaterRMSvaluesthanthepositivefeedbackconditions.Conclusion:USAexhibituniqueposturalstrategiescomparedtoSSA.Theseuniquestrategiesseeminglyexhibitadirection-specificattributeandmaybeassociatedwithdivergentmotorcontrolstrategies.

简介：体育＋时代,体育的发展势必会带动多个领域的进步。当前我国把体育产业作为新的经济增长点,给予了高度重视,颁布系列纲领文件,把足球的发展上升到国家战略层面,旨在从制度上为我国体育产业的发展树立保障,前景令人关注和期待。众所周知,足球比赛判罚的公正准确性将直接影响比赛进程,关乎比赛健康发展。现代科技的进步,为足球比赛判罚的精准性注入新鲜的血液和保障。GoalControl技术时间和空间分辨率性能卓越,具备及时响应的能力,打败了Hawk－Eye和CairosGLT系统,通过严格的国际足联审核。