Dynamical changes in postural balance of vertical position in elite taekwondo practitioners within a full-year macrocycle

Aim. To study dynamical changes in statokinetic stability of 10 elite taekwondo practitioners (Masters of Sport and Candidates for Master of Sport) within a full-year macrocycle (preparatory, competitive, and recovery periods). Materials and Methods. Ten taekwondo practitioners (5 members of the RF national team and 5 members of the national team of Kazakhstan) took part in the research. Statokinetic stability indicators were measured by MBN Stabilo hardware-software system in 3 periods of training: preparatory, competitive, and recovery. Results. It was established that, irrespective of the stage of training, the general center of pressure was shifted rightwards (8.11 to 29.56 mm) in frontal and sagittal planes, which probably resulted from specific pose typical of taekwondo. In the competitive period we observed a significant drastic increase in shifts of the general center of pressure, which was especially evident from comparison of the data of tests with eyes open and closed. Values of the GCP (general center of pressure) speed in the test with eyes open were minimal during the recovery period while in pre-competitive and competitive periods they were significantly increased by 15-18% by an average. The analysis of differences between tests with eyes open and closed revealed the drastic growth of statokinesigram area in the competitive period. Conclusion. According to our findings, within the full-year macrocycle of training of elite taekwondo practitioners the competitive period was characterized by evident signs of fatigue of the central nervous system, changes in proprioception, changes in the activity of the central rhythm generator, changes in the speed of movement in a vertical position (central pattern generator - CPG), and biomechanical disturbances.