Objective. To consider the different ways of functional and physical development of individual.
Methods. Analysis of specialized scientific literature.
Results. Extreme complexity of the process of human individual development is manifested in the fact that formation and development of different structural formations of body systems occur continuously, asynchronously, and heterochronously.
Conclusion. Individual characteristics of developmental age are the most appropriate for studying, because only in such case each age period can be understood as a constituent of holistic process of individual development.