It has been found out that in the study group both before and after training a low speed of information processing and endurance rate was registered that testifies to inertia and fast fatigue of adaptation of teen volleyball players' central nervous system.The investigation of the ratio changes in productivity and the accuracy of the mental work of teen volleyball players revealed a low level of the reliability indicator before training and an average level after training that indicates a positive effect of the performed muscular load on the dynamics of the psychophysiological characteristics of young volleyball players.An analysis of the results of productivity studies, endurance, accuracy and reliability of work capacity allowed to assess indirectly the integral functional level of the nervous system of the adolescents surveyed that was defined as the average in operational rest and in the early period of restitution.The study of the results of the test "Reactions to a moving object" demonstrates the predominance of responses to anticipation that proves the dominance of excitation processes in adolescents over inhibition showing a tendency to strike a balance after training.The examined volleyball teenagers had high quantitative indicators of mental performance that declined after training and were combined with a low and medium level of its quality. This criteria as well as reliability improved after moderate physical work. The established features of urgent adaptation of the responsible departments of the nervous system of young volleyball players should be taken into account when completing teams and managing sports activities that can be a guide for training athletes on a leading principle and it will help teen volleyball players to create the prerequisites for increasing the endurance, productivity, accuracy and reliability of the central nervous system.Prospects for further research are to study the age and gender features of adaptation of the central nervous system depending on the specific physical loads and in conjunction with the activities of other executive and regulatory systems.