Title
Spectral Moments Of Mechanomyographic Signals Recorded With Accelerometer And Microphone During Sustained Fatiguing Contractions
Abstract
The aim of this study was to analyse the trends of the first three power spectral moments of the mechanomyogram (MMG) signal recorded by a microphone (MMG(MIC)) and an accelerometer (MMG(ACC)) during sustained contractions. MMG signals were recorded from the biceps brachii muscle in 14 healthy male subjects during a 3 min isometric elbow flexion at 30% of the maximal voluntary contraction. MMG absolute and normalised root mean square (RMS), mean power frequency (MNF), power spectral variance (Mc(2)), and skewness (mu(3)) were computed. For both MMGMIC and MMGACC, absolute and normalised RMS and Mc2 increased while MNF and mu(3) decreased with contraction time (P < 0.001). The rates of change of RMS over time were significantly correlated (P < 0.001) for MMGMIC and MMGACC but not correlated for spectral moments. The coefficient of variation of RMS was higher for MMGMIC than for MMGACC, while the opposite was observed for mu(3) (P < 0.05). It was concluded that higher order spectral moments of the MMG signal change during sustained contraction, indicating a complex modi. cation of the shape of the power spectrum and not just scaling of the bandwidth. This is most likely due to the additional motor unit recruitment with fatigue and to the non-linear summation of motor unit contributions to the signal. Moreover, the characteristics of MMG signals recorded with microphones and accelerometers have important differences, which should be taken into account when comparing results from different studies.
Year
DOI
Venue
2006
10.1007/s11517-006-0036-2
MEDICAL & BIOLOGICAL ENGINEERING & COMPUTING
Keywords
Field
DocType
spectral moments, microphone, accelerometer
Coefficient of variation,Mechanomyogram,Electronic engineering,Spectral density,Motor unit,Root mean square,Acoustics,Isometric exercise,Mathematics,Microphone,Motor unit recruitment
Journal
Volume
Issue
ISSN
44
4
0140-0118
Citations 
PageRank 
References 
3
1.45
1
Authors
6
Name
Order
Citations
PageRank
Pascal Madeleine1184.30
Hong-You Ge231.45
Anna Jaskólska331.45
Dario Farina4915178.69
Artur Jaskólski531.45
Lars Arendt-Nielsen63710.95