Naslov
Measurement and analysis of surface myoelectric signals during fatigued cyclic dynamic contractions

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

Izvornik
Measurement (0263-2241) 27 (2000), 2; 85-92

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

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

Sažetak
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), was developed. As an indicator of muscle fatigue a change in power spectrum median frequency (MF), calculated from the spectrogram, has been used. Our method considers the maximum median frequency values during each contraction. A slope of the regression line (Hz/min) that fits maximum values of MF in a least-square sense was used as a fatigue index. Dependencies of the muscle fatigue index, as well as median frequencies at the beginning of the exercise on spectrogram analysis parameters were considered, and analysis parameters for reliable results were chosen. Values of the slope of the regression line and MF at the beginning of an exercise are in agreement with notion that rectus femoris has higher muscle fibre conduction velocity than both vasti muscles.

Izvorni jezik
Engleski

Znanstvena područja
Elektrotehnika, Kineziologija

POVEZANOST RADA