简介：Background：Theisometricsteady-statefollowingactivelengtheningisassociatedwithgreatertorqueproductionandloweractivation,asmeasuredbyelectromyographicactivity（EMG）,incomparisonwithapurelyisometriccontraction（ISO）atthesamejointangle.Thisphenomenonistermedresidualforceenhancement（RFE）.WhiletherehasbeenagreatdealofresearchinvestigatingthebasicmechanismsofRFE,littleworkhasbeenperformedtounderstandtheeverydayrelevanceofRFE.ThepurposeofthisstudywastoinvestigatewhetherneuromuscularcontrolstrategiesdifferbetweenISOandRFEbymeasuringtorquesteadinessofthehumanankleplantarflexors.Methods：FollowingISOmaximalvoluntarycontractionsin12males（25±4years）,anactivelengtheningcontractionwasperformedat15°/sovera30°ankleexcursion,endingatthesamejointangleasISO（5°dorsiflexion;RFE）.SurfaceEMGofthetibialisanteriorandsoleusmuscleswasrecordedduringalltasks.Torquesteadinesswasdeterminedasthestandarddeviation（SD）andcoefficientofvariation（CV）ofthetorquetraceintheISOandRFEconditionduringactivation-matching（20%and60%integratedEMG）andtorque-matching（20%and60%maximalvoluntarycontraction）experiments.Two-tailed,pairedttestswereused,withinsubjects,todeterminethepresenceofRFE/activationreduction（AR）andwhethertherewasadifferenceintorquesteadinessbetweenISOandRFEconditions.Results：Duringthemaximalandsubmaximalconditions,therewas5%-9%RFEwitha9%-11%AR（p〈0.05）,respectively,withnodifferenceinantagonistcoactivationbetweenRFEandISO（p〉0.05）.TherewerenodifferencesinSDandCVofthetorquetraceforthe20%and60%activation-matchingorthe60%andmaximaltorque-matchingtrialsineithertheRFEorISOcondition（p〉0.05）.Duringthe20%torquematchingtrial,therewere～37%highervaluesforSDandCVintheRFEascomparedwiththeISOcondition（p〈0.05）.Asignificantmoderate-to-strongnegativerelatio

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