Methods to reduce the variability of EMG power spectrum estimates
Methods to reduce the variability of EMG power spectrum estimates
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DOI：
10.1016/s1050-6411(97)00031-x
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发表时间：
1998-10-01
影响因子：
2.5
通讯作者：
Zhu, M
中科院分区：
文献类型：
--
作者：
Baratta, RV;Solomonow, M;Zhu, M
三种方法，可以显着减少的EMG功率密度谱（PDS）变量的变异性，通过消除人为成分进行了说明。两种方法：一个允许在时域中减去电力线噪声，一个允许从EMG中减去频域中的系统噪声？在帮助准确估计PDS的中值频率（MF）方面是有效的，尤其是在信噪比不利时的低水平收缩（0-25%最大自主收缩，MVC）期间。该技术消除了来自EMG记录的系统和电源线噪声的人为影响，同时在所有频率下保留了固有EMG功率。研究还表明，如果采用一种训练受试者产生其真实MVC的技术，则产生的绝对力/扭矩可能比未经训练的MVC高出30%。真正的MVC生产的影响也被证明是显着的PDS变量的解释时，产生收缩的过程。(C)1998爱思唯尔科技有限公司版权所有。
Three methods that can significantly reduce the variability of the EMG power density spectrum (PDS) variable by eliminating artifactual components are described. Two methods: one that allows the subtraction of power line noise in the time domain and one which allows the subtraction of system noise in the frequency domain from the EMG? were shown to be effective in helping to accurately estimate the median frequency (MF) of the PDS, and especially during low level contractions (0-25% maximal voluntary contraction, MVC) when the signal-to-noise ratio is unfavorable. The techniques eliminate the artifactual effects of system and power line noises from the EMG recordings throughout the force range (0-100% MVC) while preserving the native EMG power at all frequencies. It was also shown that if a technique to train subjects to produce their true MVC is employed, the absolute force/torque produced could be as much as 30% higher than in untrained MVC. The effect of true MVC production was also shown to be significant when interpretation of PDS variables are correlated to the processes which produce contraction. (C) 1998 Elsevier Science Ltd. All rights reserved.