Interaction of systems of vertical posture regulation and voluntary movement in athletes

Objective: Interrelations of functional systems of balance regulation in vertical posture and control of voluntary movements in athletes specialized in wrestling, weightlifting, and ski jumping were studied. Material and methods: The study involved highly skilled athletes aged 20-28. The interrelations between the two regulation systems were studied under conditions of rest, sensory deprivation, changes in posture biomechanical characteristics, and other complications. Results: The results reflect a strong combined influence of the examined biomechanical and physiological characteristics of the vertical posture on the reproduction accuracy of voluntary movement parameters, the manifestation of the maximum strength of athletes. Among biomechanical factors, the greatest influence on the stability of equilibrium and accuracy of voluntary movement is exerted by the area of standing support, whereas among physiological factors - the displacement amplitude of the body general center of mass (GCM). Correlation, factor, and regression analysis reflect the close relationship between the mechanisms of vertical posture regulation and the examined voluntary movements. A significant impact of various factor interactions on the accuracy of the dosed effort reproduction, the displacement amplitude of voluntary movement along a given trajectory, the manifestation of maximum force on the finger dynamometer, and during jumps on a dynamometer platform was revealed. Each pose parameter influences that of voluntary movement both directly and through interaction with other parameters. The smaller the parameter shifts of posture stability and voluntary movement under the influence of confounding factors and disturbances, the more autonomously and economically they function, the weaker their interrelation, and the higher their functional reserves. Conclusions: The rearrangement of the posture preceding the movement determines the quality of the subsequent voluntary motion. One of the important criteria for functional reserves of the "posture - voluntary movement" system is the principle of "the least interaction" in the relationship between two regulation systems. Minimization of tremor amplitude and body GCM oscillations is an indirect criterion of functioning quality of the "posture - voluntary movement" system as well as the sensitivity of the proprioceptive sensory system in athletes. Mathematical models reflecting the interrelations of posture and voluntary movement regulation systems can be used to predict the performance of an athlete and be the basis for posture and movement correction in the training process.