Torque, Work, Power, and Muscle Activity Analysis According to Self-Selected Slow, Moderate, and Fast Angular Velocity for Knee Extension

Purpose:The performance of a task is influenced by the perception of its demands and the development of a response according to the movement pattern.This study aims to compare the change in kinetic variables and quadriceps muscle activity according to demands on angular velocity.Methods: Thirty-eight participants performed knee extensions at self-selective angular velocities of slow, moderate, and fast.Angular velocity, kinetic variables, and muscle activity (vastus medialis, vastus lateralis, and rectus femoris) were measured using a dynamometer and surface electromyography.kinetic variables and muscle activity of the knee extensors at three self-selected angular velocities were compared and correlations between the variables were analyzed.Results: There were significant differences in muscle activity and kinetic variables among angular velocities (p< 0.001).Self-selective angular velocity was positively correlated with muscle activities and kinetic variables (p< 0.001).The power in fast was 40 times higher than that in slow velocity. Conclusion:The simultaneous increase in angular velocity and force output was based on increased effort.The highest power was indicated for the fastest movement.We discovered that muscle activity and torque increased at a similar rate for increasing demands on angular velocity.The individual's most appropriate pattern would have been applied at the movement of self-selective angular velocity, and fast movement is considered to have the highest efficiency.