등속성 운동 시 근전도 주파수 분석에서 얻은 피로지수의 특성

Abstract

In rehabilitation programs involving muscle re-education and endurance exercise, it isnecessary to confirm when fatigue occurs. It is also necessary to quantify fatigue, toconfirm whether the muscle has been exercised sufficiently. In general, as fatigueoccurs, the force-generating ability of the muscle is reduced. If the median frequency(MDF) obtained from electromyogram (EMG) power spectrum is correlated highly withwork, then the timing and degree of fatigue may be confirmed. This study examined therelationship between work and MDF obtained from the EMG power spectrum duringrepetitive isokinetic exercise. Surface EMG signals were collected from biceps brachiiand vastus lateralis of 52 normal subjects (26 males, 26 females) at 120°/sec and 60°/secwhile performing an isokinetic exercise. The exercise wes finished at 25% of peak work. MDF data was obtained using a moving fast Fourier transformation (FFT), and randomnoise was removed using the inverse FFT, then a new MDF data was obtained fromthe main signal. There was a high correlation between work and MDF during repetitivisokinetic exercise in the biceps brachii and vastus lateralis of males and the bicepsbrachii of females (r=.50 ~.77). However, there was a low correlation between work andMDF in the vastus larteralis of females (r=.06~.19).