This research aims to identify the impact of functional strength exercises on core muscles and the level of technical performance of L-cross skill on the rings apparatus in gymnastics. The gymnastics team players at Qassim University, and the basic research sample included (10) players, while the exploratory study was conducted on a sample of players representing the original community and from outside the basic research sample. Its training loads, and the most important results were as follows, the percentage of improvement in the strength variable of the abdominal muscles was (39.8%), and the percentage of improvement in the variable of strength of the back muscles was (28.7%), and the percentage of improvement in the variable of strength of the muscles of the legs reached (25.3%), while the percentage of improvement in the fixed balance variable was (19.3%), and finally the percentage of improvement in the technical performance variable understudy was the skill L-cross (24.9%), and the researcher recommends using functional strength exercises to develop core muscular strength and level of technical performance of the L-cross skill on the rings apparatus in gymnastics.