The structure of the human biological rhythm is most sensitive to changes that occur when you alter usual living conditions. That is why the authors of the work devoted their attention to the study of its basic parameters such as the analysis of the daily regimen, taking into account the “wakefulness and rest” cycles, the sleep quality index, the severity of insomnia. These parameters directly affect the person’s efficiency and results of sports activities. The authors have developed a system for the electronic diagnosis of human biorhythms. You can get acquainted with it at the open educational resources of V.N.Karazin Kharkiv National University. In the work, for the first time, the basic cycles of “wakefulness and sleep”, “activity and rest” were evaluated as basic cycles of the day regimen of students professionally involved in sports using electronic diagnostics. Insomnia severity index was evaluated, which directly affects the psychosomatic state and can be a cause of violation of the dynamic stereotype of a person, deterioration of health. These factors contribute to the development of desynchronosis. The data obtained indicate that the surveyed group of individuals can quite easily adapt to work both in the morning and in the evening, but it is likely that these individuals have unnatural types of daily working capacity, which are manifestations of adaptation to new living conditions. Also, this group of people is characterized by medium and high levels of sleep quality and body recovery. It is easier for people of this group to fall asleep in non-standard conditions than to stay awake at unusual time. Modern youth, despite an active (sporty) lifestyle, has certain violations in the duration and nature of sleep. The data obtained indicate that reducing the duration of sleep by 1.3–1.5 hours directly affects the state of wakefulness and sleep during the day. Despite the fact that chronic sleep deprivation in this group of students professionally involved in sports has not been identified, some individual variations in the need for quality of sleep are revealed, after a long sleep, there is minimal improvement in daytime wakefulness, reduction of fatigue, improvement in the processes of memory, perception and concentration. All these indicators directly affect the sports result. Compensation of lack of nocturnal sleep is mainly possible only due to longer breaks for rest during the day. Thus, the need for sleep is determined on the one hand by the processes of relaxation and fatigue, which increase during wakefulness, and the circadian process – the cycle of “activity and rest”. The level of need for sleep increases during wakefulness and decreases during sleep, while the circadian rhythm is an independent component under the control of the internal biological clock. Thus, the need for sleep at any given moment is a summation of the processes of “activity and rest”, “wakefulness and sleep” and internal...