基于肌阻抗图的非侵入式新型肌疲劳标记物

A New Non-invasive Marker of Muscle Fatigue Based on Electrical Impedance Myography

目的:肌肉疲劳广泛存在于日常生活中。针对在运动场景下,传统的肌阻抗图(Electrical Impedance Myography, EIM)参数(幅值、相位)存在实时性不足等问题,结合生物组织等效电路模型开展肌肉疲劳电抗响应分析,提出新的EIM肌肉疲劳标志物。方法:本文根据电抗-频率的特定关系,提出一种电抗峰值频率(Reactance peak frequency, f_(c))标定肌疲劳的方法,并结合生物电阻抗特征方程,设计f_(c)的求解算法,获取相关特征参数R_(0)、R_(∞)、α、τ。再次搭建肱二头肌肌肉疲劳在体实验平台,探究由疲劳引起的电抗响应特性,验证f_(c)表征肌肉疲劳的有效性。结果:在疲劳过程中,f_(c)随运动周期的增加呈下降趋势,疲劳后的f_(c)下降范围为4~11 kHz。经皮尔逊相关性检验,f_(c)与肌疲劳程度表现出负相关性,平均相关性系数的绝对值大于0.98,肌肉疲劳前后的f_(c)具有显著性差异(p<0.05)。结论:电抗峰值频率在运动过程中以及运动前后的特定偏移有望作为一个新的肌肉疲劳标志物。

Purpose:Muscle fatigue is widespread in daily life.In view of the problem that the traditional parameters(amplitude and phase)of electrical impedance myography(EIM)are not real-time enough in the motion scene,this paper combines the biological tissue equivalent circuit model to carry out muscle fatigue reactance response analysis and proposes a new EIM muscle fatigue marker.Method:According to the specific relationship between reactance and frequency,a method to calibrate musrcle fatigue with reactance peak frequency was proposed.Combined with the bioelectrical impedance characteristic equation,the solution algorithm of f_(c)was designed to obtain the relevant characteristic parameters R_(0)、R_(∞)、α、τ.Secondly,an in vivo experiment platform for biceps brachii muscle fatigue was built to explore the response characteristics of reactance caused by fatigue and verify the effectiveness of peak frequency of reactance to characterize muscle fatigue.Result:In the process of fatigue,there was a downward trend of f_(c)with the increase of motion cycle,and the decline range of f_(c)after fatigue was 4-11 kHz.Through Pearson correlation test analysis,f_(c)and muscle fatigue showed a negative correlation,the absolute value of average correlation coefficient was greater than 0.98,f_(c) of before and after muscle fatigue had a significant difference(p<0.05).Conclusion:The specific shift of peak reactance frequency during and before and after exercise is expected to be a new marker of muscle fatigue.