Model for calculating the strength of fast and slow motor units in isometric mode using the example of knee extensor muscles

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Dr. Biol. A.V. Voronov1
PhD A.V. Shpakov1, 2
A.A. Voronova1
N.N. Sokolov1
1Federal Science Center of Physical Culture and Sport (VNIIFK), Moscow
2State Scientific Center of the Russian Federation - Institute of Biomedical Problems of the Russian Academy of Sciences, Moscow

Objective of the study was to determination of MDE and BDE forces depending on sports specialization.
Methods and structure of the study. In an experiment to evaluate the maximum strength of MDE and BDE m. quadriceps athletes members of Russian national teams in various sports took part: 64 boys and men and 17 girls and women, testers from the State Research Center of the Russian Federation for IBMP (n=10). Study participants performed knee extensions in a sitting position. Moments m. quadriceps were recorded on an isokinetic simulator «BIODEX System 4 Pro» at angular velocities in the range of 30-300 deg/s. Maximum isometric strength was assessed at knee joint angles of 90 degrees.
Results and conclusions. Based on the results of isokinetic dynamometry and a mathematical model, fast fnd slow muscle units FMU and SMU forces were calculated for highly skilled athletes of different sports. For athletes of different specializations, the SMU force does not exceed the value of 24 N/kg, the FMU force is in the range of 52-83 N/kg.

Keywords: strength of type I and II fibers, force-velocity, maximum force m. quadriceps, strength training, mathematical modeling.

Работа выполнена в рамках государственного задания ФГБУ ФНЦ ВНИИФК № 777–00001–24–00 (код темы № 001–22/4).

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