ASSESSMENT OF THE ABILITY TO TENSE AND RELAX MUSCLES IN HIGH QUALIFIED SKIERS-RACERS

The purpose of the research is to experimentally determine the ability to tense and relax muscles in a time interval in highly qualified cross-country skiers.

Methods and organization of the research. The study involved highly qualified ski racers, 18 men and 15 women. All of them are masters of sports in cross-country skiing. As a result of studies measuring the speed of contraction and relaxation of the muscles of the lower extremities, an index of muscle relaxation efficiency is determined.

Research results and their discussion. In the course of research, it was found that the value of the muscle relaxation efficiency index (Ir) in highly qualified ski racers is not the same for different muscle groups. Based on the purpose and objectives of the research, using the tensodynamography method, objective data were obtained on the level of strength and speed-strength training of highly qualified ski racers. 
Determining the values of the muscle relaxation efficiency index (Ir) when performing explosive efforts in the isometric mode increases the effectiveness of assessing the speed-strength fitness of highly qualified ski racers.
The article presents research on the ability of highly skilled ski racers to relax their muscles in short periods of time. The ability of a skier to regulate the ratio of multiple muscle contractions while covering cross-country skiing distances up to 1000 or more times during the push-off period, followed by relative relaxation during the period of the flywheel of the leg, are the leading indicators of the expenditure of energy resources of a skier-racer. There is no doubt that the ability to relax, and therefore partially restore energy reserves in muscle tissue during the swing movement of the leg and arm, will help maintain the speed of movement.

Conclusion. Determining the ability to tense and relax leg muscles in a time interval in laboratory studies, in our opinion, suggests the preservation of energy reserves in the athlete’s body through restoration, which are the limiting factor in maintaining the speed of movement of a skier-racer.
 

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