The research aims to identify the effect of the maximum physical exertion on some physiological variables which is (respiration rate - the maximum absolute and relative oxygen consumption - respiratory factor - the rate of oxygen consumption per pulse), and on some rare blood salts (iron - zinc - selenium - copper) for swimming 100 m free for young men, and the researcher used the experimental method on a sample consisting of (15) swimmers from Al-Rowad Club in the tenth of Ramadan, and registered with the Egyptian Swimming Federation, and the researcher used the Ozycon-5 device to determine the access to the maximum physical effort, and blood samples were also drawn to measure the level of rare salt in the blood, And from They are the results: The maximum physical exertion leads to an increase in some physiological variables, which is (respiration rate - the maximum absolute and relative oxygen consumption) except for the variables (respiratory coefficient - the rate of oxygen consumption per pulse), where the results demonstrate that there are differences in these variables, though not Statistically significant, as well as to increase the concentration of rare blood salts in the blood (iron - zinc - selenium -) for beginners swimmers 100 meters free, and this draws attention to the importance of following these variables when planning and following up the implementation of training units and var