高强度运动前后的人体下肢电阻抗特性变化分析

目的研究高强度运动前后人体下肢电阻抗血流信号及频谱特性的变化情况,为用电阻抗参数评价人体运动功能及疲劳程度做基础。方法利用课题组自行研制的电阻抗快速测量系统,分别测量10名志愿者高强度运动前后双侧下肢的阻抗血流信号及1 kHz^1 MHz频段的电阻抗幅值变化情况。结果阻抗血流信号变化特性显示,运动后人体双侧下肢阻抗血流信号幅度增加22%±13%。阻抗频谱特性分析显示,100 kHz以下频段,运动对下肢阻抗幅值的影响不显著;在100 kHz以上频段,运动后的下肢电阻抗幅值显著降低,测量频率越高,下降的程度越明显。1 MHz时的变化率可达53%±14%。结论人体电阻抗与其运动功能状态有着密切的关系,因而电阻抗参数有望作为一项定性甚至定量区分组织疲劳状态的重要指标。

Analysis of Changes in Electrical Impedance Characteristics of Human Lower Limbs Before and After High-Intensity Exercise

Objective To study the changes of blood?ow signals and spectral characteristics of the electrical impedance of human lower limbs before and after high-intensity exercise,and to lay the foundation for evaluating the motor function and fatigue degree of human body using electrical impedance parameters.Methods Using the electrical impedance rapid measurement system developed by the research group,the impedance blood?ow signals of the lower limbs of 10 volunteers before and after high-intensity exercise and the amplitude of the electrical impedance of 1 kHz to 1 MHz band were measured.Results The impedance blood?ow signal characteristics showed that the amplitude of the impedance blood?ow signal of the lower limbs of the human body increased by 22%±13%after exercise.The analysis of the impedance spectrum showed that the in?uence of motion on impedance amplitude of lower limb was not significant in frequency band below 100 kHz.In the above frequency band above 100 kHz,the amplitude of electrical impedance of lower limbs after exercise decreased significantly after exercise.The higher the measurement frequency,the more obvious the degree of decline.The rate of change at 1 MHz could reach 53%±14%.Conclusion The electrical impedance of human body has a close relationship with the state of motor function.Therefore,the electrical impedance parameter is expected to be an important indicator for qualitatively and quantitatively distinguishing tissue fatigue state.