This research aims to identify the effectiveness of using the T.R.X tool on developing muscle ability and the digital level of discus throw, and the researcher used the experimental method with pre and post measurement for one experimental group due to its relevance to the nature of this research, on a total sample of (13) students specialized in training athletics in the fourth year of the Faculty of Physical Education for Boys, Zagazig University for the academic year 2019/2020, ( 8 of them are the basic sample and 5 are the pilot study). The researcher recommends using the T.R.X tool in training because it is extremely important in developing the special muscular ability and the digital level of discus throw competitors, and providing the tools and devices necessary to use the training of the T.R.X tool sufficiently in proportion to modernity, safety and security requirements, And use the T.R.X tool instead of weight training for the junior stages to prevent injuries that occur to this age group from weight training.