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:8月15日,2012中国网球公开赛面向全球盛大开票。作为亚洲级别最高的综合性网球赛事,今年中网吸引到了包括德约科维奇、纳达尔、特松加和费雷尔在内的多位ATP顶尖球员前来参赛,加上强制参赛的世界排名前50的女单选手,如此豪华的阵容让众多新老球迷期待不已。2012中网的脚步越来越近,一场宏大的网球盛筵即将开启,我们一同来看看今年中网票务部门又为广大球迷准备了哪些新的惊喜。