The book presents a new scientific approach to the problem of biomechanical systems description.This approach is based on development of a universal anthropomorphic model and employment of methodology of imitational dynamic modeling (IDM). The novelty of this approach is that there appears a possibility to operate with a whole class of models, derived from the universal model on the basis of motion separation principle. This is followed by utilization of iterational procedures realizing the method of successive approximations and resulting in description of the real motion with the pre-set accuracy level. By use of the IDM there has been for the first time ascertained certain laws governing human locomotions: presence of so-called controlling and stabilizing interlink moments, wavelike speeding of forces extremums along the kinematic chain, adaptation of control functions for astronauts motion coordination preservation. The book includes new theoretical conceptions explaining the deterioration of functional state of skeletal-muscular apparatus of astronauts due to zero-gravity influence.