The aim of this research is to investigate the effect of using variable resistances exercises on developing muscular dynamic balance and perform the back throw skill by circling the arm and neck in free style wresting for wrestlers of free style wresting (20) years , The researcher used the experimental method and follow the experimental design with pre- measurement and post – measurement of two groups (experimental and controller) in order to appropriate to type of the search , the research Sample has been chosen from a group of wrestlers in the third year at physical education , zagazig university during the academic year 2020/2021 were chosen on purpose . the total of the sample reached 32 wrestlers represent , 8 wrestlers were chosen to perform survay study so the main sample became 24 wrestlers. The wrestlers were divided randomly in to two equal groups, Experimental group and controller group (each group has 12 wrestlers , Programe application been applied to the training programe using variable resistances exercises that develop the coordination abilities for interoperability wreslers in the main part of the module the experimental group in three training unint during eight weeks , from 3/10/2020 to 25/11/2020and time of daily traing unit 60-80 m , , and the results of training program improved significantly in the level of development Effect of using variable resistances exercises on developing muscular dynamic balance and perform the back throw skill by circling the arm and neck in free style wresting for wrestlers 20 years