THE EFFECTIVENESS OF USING STRENGTH EXERCISES WITH DIFFERENT POSTURAL CONTROL STRATEGIES IN INCREASING THE COMPETITIVE PERFORMANCE OF HIGHLY QUALIFIED SKI JUMPERS

The purpose of the research: to evaluate the influence of methods of using strength exercises with different postural control strategies on the performance of competitive ski jumping in highly qualified athletes.

Methods and organization of the research. During the experiment, conducted between 2021 and 2023 with representatives of the Russian national ski jumping team, the effectiveness of two methods of using strength exercises during the preparatory period was compared. The first «traditional» technique involved the use of non-biomechanically specialized strength exercises under conditions of stable support, aimed at increasing maximum and explosive strength, and specialized exercises without weights on an unstable support, which simulated the phases of repulsion from the lift-off table or control of the working posture on the lift-off table.
The second «alternative» technique involved the use of three sets of strength exercises, not specialized in biomechanics: exercises performed under conditions of unstable support, or unstable weights, or in combination – under conditions of unstable support and unstable weights. 
The evaluation of the effectiveness of the influence of the studied methods was carried out by the method of control tests (performing a competitive exercise on the K-90 and K-120 springboards) as well as by the method of expert assessment (evaluation of equipment).

Research results and their discussion. The «alternative» technique is more effective than the «traditional» technique in terms of technique and length of the high power springboard jump (K-120). For the medium-power springboard (K-90), the «alternative» technique is effective in increasing acceleration speed and jump distance, while the «traditional» technique significantly improves only acceleration speed.

Conclusion. The «alternative» technique has a greater strength of training influences (size of effect) in the summer training period in relation to the technique and distance of a high-power ski jump, and in the winter competitive period in relation to the acceleration speed and distance of a medium- and high-power ski jump.

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