Naslov
Surface myoelectric signal spectral analysis during fatigued dynamic contractions of quadriceps muscle

Autori
Cifrek, Mario ; Tonković, Stanko ; Medved, Vladimir

Vrsta, podvrsta i kategorija rada
Radovi u zbornicima skupova, cjeloviti rad (in extenso), znanstveni

Izvornik
Proc. of the 8th International IMEKO Conference on Measurement in Clinical Medicine, BMI’98 / Magjarević, Ratko - Zagreb : Hrvatsko društvo za komunikacije, računarstvo, elektroniku, mjerenja I automatiku (KoREMA), 1998

Skup
8th International IMEKO Conference on Measurement in Clinical Medicine, BMI’98

Mjesto i datum
Dubrovnik, Hrvatska, 16.09.1998. - 19.09.1998

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
muscle fatigue; time-frequency analysis; dynamic contractions; surface electromyography

Sažetak
The purpose of this study was to develop a method of surface myoelectric (ME) signal measurement and analysis with the aim of evaluating muscle fatigue during cyclic dynamic contractions of quadriceps muscle (lower leg extension and flexion exercise on leg-extension training device). As an indicator of muscle fatigue a change in power spectrum median frequency (FM, frequency which divides a power spectrum into two equal power halves), calculated from the spectrogram, has been used. Because of requirements for ME signal stability, our method considers the maximum median frequency values (which corresponds to the maximal extension) during each contraction. A slope of the regression line (expressed in Hz/min) that fits maximum values of FM in a least-square sense was used as a fatigue index. Our study has shown decreases in FM in the range from -3.7 Hz/min to -27.3 Hz/mi, depending on subject and muscle. Furthermore, our results show that the values of the FM at the beginning of an exercise are in agreement with available information about dominant muscle fibre type in observed muscles.

Izvorni jezik
Engleski

Znanstvena područja
Elektrotehnika

POVEZANOST RADA