INFLUENCE OF EXERCISES PERFORMED IN CONDITIONS OF STABLE AND UNSTABLE FORCE FIELD ON INDICATORS OF STRENGTH ABILITIES OF HIGHLY QUALIFIED SKI JUMPERS

The purpose of the research: to evaluate the effectiveness of strength training in ski jumpers aimed at developing maximum, explosive and fast strength, using exercises performed under stable force field conditions and training with the combined impact of exercises performed under stable and unstable force field conditions.

Methods and organization of the research. The study was conducted on 16 male members of the Russian national ski jumping team from May to October 2022. The study compared the effectiveness of two methods of using strength exercises during the preparatory period. Athletes of group 1 (10 people) trained according to the «traditional» method, which involved the use of only strength exercises performed under conditions of stable support, aimed at increasing hypertrophy, maximum, explosive and fast strength. Athletes of group 2 (6 people) trained using an «alternative» method, in which the use of strength exercises similar to the «traditional» method (70%) was combined with the use of three sets of strength exercises, not specialized in biomechanics: exercises performed in conditions of unstable support, either unstable weights, or in combination – in conditions of unstable support with unstable weights (30%). The isokinetic dynamometry method was used to assess the strength abilities of the flexor and extensor muscles of the knee joint of the right and left limbs (data obtained on the Biodex System 4 Pro robotic complex were used). To assess the «degree of influence» of the training effects of each technique on different types of strength abilities, the «effect size» was calculated.

Research results and their discussion. The type of force field instability in the exercises used determines the effectiveness of developing maximum, explosive or fast strength. The most effective from the point of view of developing the absolute values of strength abilities is a combination of exercises performed on an unstable support and «combos» in the mode of explosive and fast strength. At the general and special preparatory stages, strength exercises performed under conditions of an unstable force field, in combination with «traditional» exercises, have a lesser training effect on muscle speed abilities compared to exercises performed under conditions of a stable force field.

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