Objective. Analysis of current notions about body functional state formation, problems of psychophysiological understanding of athlete reliability.
Methods. Review of literature data concerning the significance of neurodynamic, psychological, personal and socio-psychological factors, which determine athlete reliability.
Results. The importance of functional system theory (according to P.K.Anokhin) with respect to prediction and evaluation of body adaptive capacities as well as the character of occurring failures in the activity of individual components of functional systems and body on the whole have been stressed. Linguistic method for analysis of ultra-stability of physiological system functioning, including description of periodical constituents of physiological processes has been suggested for estimation of athlete body tension.
Conclusion. The efficient means of athlete reliability provision is psychophysiological preparation, which forms the system of nervous connections, formation of body functional systems and specialized dynamic stereotypes.