Analysis of strength indicators of the muscles of the lower extremities: an instrumental method

Abstract

Objective of the study was to adapt an instrumental method for assessing the strength of the leg extensor muscles and test its effectiveness in various sports. Methods and structure of the study. To assess the strength and speed-strength capabilities of the leg extensor muscles in female athletes, the computer tensodynamography method was used, consisting in recording and analyzing the «strengthtime » curve. Based on the obtained tensodynamometric curves, the maximum isometric muscle strength (F max) demonstrated in the described movement, the time (t max) during which the maximum effort was achieved were determined. The following were calculated: the differential index (gradient) of strength (I), characterizing the rate of its increase to the maximum (I = F max / tmax), the force achieved in 0,1 s, as well as strength indicators relative to the body weight of the athletes. The experiment involved female athletes aged 15-17 (n = 36), specializing in short and middle distance running, as well as in ice hockey. Results and conclusions. An instrumental method for assessing the strength characteristics of the leg extensor muscles has been improved and tested. Its use for pedagogical control over the dynamics of athletes' condition in sports practice conditions has shown a positive effect. The dynamometric characteristics of the leg extensor muscles in the isometric mode obtained using the instrumental method have authenticity criteria and are recommended as tests for assessing the level of special strength training of female athletes of different specializations. Multiple regression equations have been developed for predicting the probable sports result and establishing the proper values in control exercises that determine the planned sports result, which can be used in practice for individual correction of the training process of female athletes. The dynamometric measurements of the leg extensor muscles, obtained using the new method in an isometric mode, have been validated as reliable indicators. They are recommended as tests for assessing the level of athletes' special strength training across various disciplines. To predict athletic performance and set appropriate benchmarks for control exercises that contribute to achieving the desired athletic result, multiple regression equations have been created. These equations can be used in practice to tailor the training process for individual athletes.