The researcher's approach include including running and plyometric exercises into advised training cycles. With the support of this strategy, the central nervous system will be able to activate fast fibers in very acidic conditions, enhancing speed and strength endurance and ultimately performance. The study's objective was to examine the effects of combining running and plyometric exercises with suggested circuits on the development of speed endurance, strength endurance, and the capacity to run the 1500 m in less than 20 years. The experimental design of the research involved two equal groups (the control and experimental groups), a pre-test, and a post-test. For the 1500 m race, 16 runners under the age of 20 from the governorates of the Middle Euphrates (Karbala, Babil, Najaf, and Diwaniyah) and the capital, Baghdad, made up the research population. For his study, the researcher selected a sample of 10. The runners were chosen at random. Accordingly, 62.5% of the research population was represented by the sample. The sample was similarly split into two groups, control and experimental, with five runners in each group.

The researcher reached the following important conclusion: The exercises he designed and executed using a combination of running and plyometric exercises helped develop the central nervous system's effectiveness in mobilizing the greatest number of fast-twitch fibers under highly acidic conditions, which significantly aided in the development of speed endurance, strength endurance, and achievement among participants in the experimental research sample. The expert advised taking into account studies and research that demonstrate the strong relationship between the central nervous system and endurance.