Reliability in kimono grip strength tests and comparison between elite and non-elite Brazilian Jiu-Jitsu players

Abstract

BackgroundThegripstrengthenduranceisimportantforBrazilianJiu-Jitsu�(BJJ).�Thus,�theaimsofthisstudywere:�a)�totest� thereliabilityoftwokimonogripstrengthtestsnamedmaximumstaticlift�(MSL)�andmaximumnumberofrep- etitions�(MNR)�andb)�toexaminedifferencesbetweeneliteandnon-eliteBJJplayersinthesetests. �:� ThirtyBJJplayersparticipatedintotwophases:�A�totestreliabilityand�B�tocompareeliteandnon-elite.�In� phaseA,�twentyparticipantsperformedtheMSLand,�15�minlater,�theMNRintwooccasionswith�24-hinter- val.�InphaseB,�tenotherBJJpractitioners�(non-elite)�andtenathletes�(elite)�performedthesametests.�Thein- traclasscorrelationcoefficient�(ICC)�twowayfixedmodel�(3,1),�Bland-Altmanplotandthelimitsofagreement� wereusedtotestreliability,�correlationbetweenthetestswereevaluatedbyPearsoncorrelationsandindependent� Ttest�(P<0.05)�wasutilizedtocompareelitevs. non-elite. � Results:� TheICCwashighforrepeatedmeasurementsondifferentdaysofphaseA�(MSL:�r=0.99�andMNR:�r=0.97).� Limitsofagreementfortimeofsuspensionwere�-6.9�to�2.4-s,�withameandifferenceof�-2.3�s�(CI:�-3.3�to�-1.2-s),� whilefornumberofrepetitionsthelimitsofagreementwere�-2.9�to�2.3-rep,�withameandifferenceof�-0.3-rep� (CI:�-0.9�to�0.3-rep).�InphaseB,�elitepresentedbetterperformanceforbothtests�(P<0.05)�comparedtonon- elite�(56±10-svs. 37±11-sinMSLand�15±4-repvs. 8±3-repinMNR).�Moderatecorrelationwerefoundbetween� MSLandMNRforabsolutevaluesduringtest�(r=0.475;�p=0.034),�andretestphases�(r=0.489;�p=0.029),�while� moderateandhighcorrelationsinthetest�(r=0.615;�p=0.004)�andretestphases�(r=0.716;�p=0.001)�werefound� forrelativevalues,�respectively. � Conclusions:� Theseproposedtestsarereliableandbothstaticanddynamicgripstrengthendurancetestsseemtodifferentiate�