Distribution rates analysis of symplectic geometry spectrum for surface EMG signals on healthy hand muscles

The assessment of muscle function has been an intractable issue in several fields of biomechanics, sports medicine and rehabilitation medicine. The surface EMG signals are often used to evaluate the muscle function. However, even for the muscles of the healthy hands, some characteristics of the surface EMG signals are also usually obviously different, such as the values of amplitude, mean spectral frequency, etc. It is difficult to use these values as the reference standards to assess the corresponding muscles. For this, this paper applies a kind of the nonlinear values---the distribution rates of the symplectic geometry spectrum (SGS) method to analyze the surface EMG signals. By comparing the distribution rates of SGS between the original surface EMG signals and their surrogate data, the results show that the surface EMG signals are not from a random process but a nonlinear deterministic process. And the distribution rate value can be taken as a reference standard to analyze the surface EMG signals.