We studied the features of development of oxidative and nitrosative stress in otherwise healthy individuals under the influence of prolonged exercise of high volume and intensity. It is shown that young men who systematically performed muscular work have a high content of markers of different ways of generation of superoxide radical, a reactive oxygen species for products of lipid peroxidation and markers of nitrosative stress. The increase in the degree of adverse effects on the body intensive training and competitive loads is accompanied by pronounced adaptive changes in the hierarchy of oxidizing constitutive de novo synthesis of nitric oxide, as well as its nonoxide reutilization synthesis (in 3 times higher). Disadaptation of the organism of boys at the end of the competition period is reflected in growing levels of generation of ROS (superoxide radical: 3,5 times higher, hydrogen peroxide: 2,5 times higher). The products of purine nucleotides degradation were 2 times higher, and the increase in the content of the nitrate anion was 2,5 times higher.