The The last two decades there has been a growing interest in the nitric oxide (NO) function in the body of a healthy person. In the study, two very specific problems are discussed: a) the NO involvement in mechanisms of adaptation at muscular work under hypoxia conditions, and b) the inorganic nitrate supplementation in athlete’s diet with the aim of sports performance improvement. The reorganizations that occur in the heart vasculature and in skeletal muscle for providing muscle work under hypoxia conditions examined. The named problems are particularly relevant in contemporary sports in which the adding of hypoxic exposure on a body of training persons as well as the inorganic nitrate in sports nutrition application as added means to special performance improvement. Raise the problem of the hypoxia and inorganic nitrate mutual exploitation in the training process.