STRATEGIES OF BODY STABILITY CONTROL IN COMPLEX STATIC BALANCES OF RHYTHMIC GYMNASTICS

The aim: to identify strategies for controlling a static posture of a gymnast under various mechanical conditions for maintaining body stability. Materials and methods. The study involved 12 athletes aged 18 to 20 engaged in rhythmic gymnastics who has obtained a Master of Sports title. The following methods were used: stabilometry utilizing Stabilan-01-2 computer stabilo-analyzer (Russia), biomechanical modeling and the calculation method. Results. The paper contains the results of a comparative biomechanical and stabilometric study of the "arabesque" static posture performed by gymnasts in three standing positions: a knee stand, one foot stand and a toe stand. Elaboration of calculation and analytical schemes has resulted in obtaining of the following biomechanical characteristics: the center of gravity (CG) of a gymnast, a take-off area, stability angles, the moments of gravitational force and the articular moments. A comparative analysis of biomechanical characteristics has made it possible to determine that the most favorable conditions for maintaining stability of a gymnast’s position appear in a knee stand, while unfavorable conditions have been recorded in a toe stand. The results of the study of physiological parameters of balance function revealed statokinetic indicators which turned out to be the most “sensitive” to alterations of mechanical conditions of balance. These are the statokinesiogram length along the sagittal axis (Lу, mm), the mean CSD velocity (V, mm/sec), the working area of take-offs (EllS, sq. mm). We have revealed a variable nature of internal controlling effects while maintaining the arabesque position depending on the mechanical conditions. Conclusion. A three-link model of an inverted pendulum with different posture control strategies is proposed: “hip” - in a knee stand, “ankle” - in one foot stand, and “ankle-phalanx” - in a toe stand.

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