The purpose of this paper is to preparing water exercises on different surfaces and explosive exercises to develop some of the physical abilities and physiological indicators of 100 m runners under 20 years of age and identifying the effect of water exercises on different surfaces and explosive exercises on some of the physical abilities and physiological indicators of 100 m runners under 20 years of age and knowing the difference in the effect. Between the training program based on water exercises and explosive exercises, the research was conducted in the period from (1/7/2022 to 1/4/2023) and on a sample of runners from Najaf Governorate under 20 years old. The number of the sample reached (10) runners and they were divided into two groups. Two equal experiments, one representing explosive exercises and the other aquatic exercises. Each group (5) runners was formed after conducting the homogeneity and equivalence processes. The appropriate tests specified by the researcher were also chosen, taking into account the opinions of experts and specialists, while conducting the exploratory experiment on a group of players from outside the basic research sample, with the use of tools and the means to assist in the research. Pre-tests were conducted on the two experimental groups, and then the method prepared by the researcher was applied: explosive exercises and water exercises for both experimental groups, which amounted to (8) weeks (24) units, each week three units, and the time of one unit was (90) minutes, after which the Posttests for both groups. Then, the research results were processed using the statistical package (SPSS). The researcher came up with specific and important conclusions, the most important of which was that there was an improvement in all the physiological indicators investigated (vo2max, disability, oxygen debt, and heart rate) for the 100 m runners (under 20 years old) for the first and second experimental groups that used explosive exercises. There is also an improvement in all the physical variables investigated and the achievement (100 m) for 100 m runners (under 20 years old). For the first and second experimental groups, and in light of these conclusions, the researcher recommended the necessity of trainers adopting 100-meter runner training in explosive exercises, even if only in some parts of the training curricula. It is necessary for trainers to pay attention to physiological indicators, as they are indicators of the adaptation of the functional systems in the body and their influence in revealing the training situation, especially the indicators studied. Emphasizing on coaches and those in charge of the training process the necessity of conducting tests for the physiological indicators related to the effectiveness or game before preparing any training curriculum and not relying on physical tests only.