referstomusclecontractionexercise;orspecificpostureexercisebasedonit.Almostallmovementsofmetazoansbelongtomusclemovement,whichcanbedividedintothefollowingthreemainforms:
(1)Thetissuemovementofmuscleentities:suchasthebodyofflatanimals,thefeetofmollusksandmammals.Thetongue,etc.,aremuscletissuescomposedofcriss-crossedmusclefibers,thatis,movementcausedbymusclesolidtissues,whichcanfreelychangebodyshapethroughflexion,extension,andflattening.
(2)Tubularmusclemovement:itisthemovementofthehollow-arrangedmuscletissue,thatis,thetubularmuscle,suchasthebeatingoftheheartandtheswimmingmovementofjellyfishandsquid,whicharecausedbyrapidcontractionandrelaxation.Pumpaction.Thetubefootmovementofechinodermsalsobelongstothiskindofmovement.
(3)Skeletalmusclemovement:Thisisthemovementgeneratedbytheactivesurfaceofthemusclesspanningthemovablejointontheinnersurfaceoftheexoskeletonortheoutersurfaceoftheendoskeleton,basedontheleverageofthetrunkandappendages.Variouslocalmotionsandmobilemotions.