THE INFLUENCE OF STRENGTH EXERCISES PERFORMED IN CONDITIONS OF STABLE AND UNSTABLE FORCE FIELD ON THE VERTICAL POSTURE CONTROL OF SKI JUMPERS

The purpose of the research: to compare the effectiveness of two methods of strength training for highly qualified ski jumpers according to the criterion of the impact of exercises performed in conditions of a stable and unstable force field on the neuro-motor mechanisms of controlling the vertical working posture of athletes.

Methods and organization of the research. The content of the two-year pedagogical experiment included a comparison of two methods of strength training of highly qualified ski jumpers during the preparatory period: 1st group (10 people) performed strength exercises in a stable force field; 2nd group (6 people) combined «traditional» strength exercises (70%) and exercises performed in a single workout in conditions of an unstable force field (30%). The stabilometry method (the «Triangle» test procedure) was used to assess the neuro-motor mechanisms for controlling the vertical working posture of athletes. Hypotheses about the reliability of statistical differences between and within groups were tested on bootstrap-generated samples using the calculation of the Mann-Whitney-Wilcoxon criterion (MWW/MWU) for a 5% significance level.

Research results and their discussion. The data obtained indicate various options of the influence of strength exercises, performed in conditions of an unstable force field, on the number, power and accuracy of cognitive and motor corrections when controlling vertical posture of ski jumpers, depending on the specified instability conditions, the magnitude of external resistance and the mode of muscle work.

Conclusion. When planning the strength training of ski jumpers during the preparatory period, it is advisable to include exercises performed in conditions of an unstable force field, taking into account their influence on the control mechanisms of the working posture and in strict accordance with the stage tasks of technical improvement of jumpers on springboards of various powers.

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