基于sEMG时频分析的递增负荷诱导肌肉周期动态疲劳估计  

Assessing Increasing Load Induced Muscle Fatigue during Periodic Dynamic Contractions Based on Time-frequency Analysis of sEMG Signals

作　　者：李世明[1,2] 许全盛[3] 翟佳丽[4] 部义峰[5] 韩立明[2] 

机构地区：[1]中国海洋大学体育系,山东青岛266100 [2]鲁东大学体育学院,山东烟台264025 [3]燕山大学电气工程学院,河北秦皇岛066004 [4]滨州医学院康复医学院,山东烟台264003 [5]江苏师范大学体育学院,江苏徐州221116

出　　处：《中国体育科技》2016年第3期48-55,共8页China Sport Science and Technology

基　　金：山东省自然科学基金资助项目(ZR2013AL010);中国博士后科学基金特别资助项目(2013T60630)

摘　　要：利用信号的时频分析技术,对递增负荷下肌肉周期性动态收缩疲劳程度进行估计。10名男性大学生完成从50-200w＋的1-5级功率自行车递增负荷蹬车实验,每级负荷采集最后5s的股直肌、股内侧肌和股外侧肌表面肌电信号,将每次向心收缩期的信号截取出来,通过乔伊-威廉姆斯分布的时频分析估计出肌电信号的瞬时功率谱,进而计算出信号的瞬时平均频率和瞬时中值频率。结果表明,瞬时平均频率和瞬时中值频率在3级负荷之后随负荷递增而近似线性递减,结合积分肌电同时随负荷递增而近似线性递增的特征,可反映递增负荷下肌肉动态收缩疲劳的发生、发展过程;由于瞬时平均频率的计算量小于瞬时中值频率,建议将积分肌电和瞬时平均频率相结合作为评估肌肉周期性动态疲劳的联合参数。This paper presents a time-frequency analysis technique to assess quadriceps femoris muscle fatigue induced by cyclic dynamic contraction.10 male college students were selected to perform cycle ergometer experiment with 1to 5step increasing load from 50 wto 200w＋.The last 5seconds sEMG signals during each load was acquired and then contraction section was cut out for time-frequency analysis.Choi-Williams distribution was used to obtain instantaneous power spectrum density and then to compute the instantaneous mean frequency（IMNF）and instantaneous median frequency（IMDF）.The results show that both IMNF and IMDF decreased approximately linearly with the increasing load after three load level,and combined with the characteristics of that integrated EMG（iEMG）increased with the increasing load simultaneously,which can identify fatigue degree induced by increasing different cycling loads.It was demonstrated that IMNF outperforms IMDF in computation efficiency so that it can be combined with iEMG to form a united parameters which can assess muscle fatigue during cyclic dynamic contraction.

关 键 词：时频分析 表面肌电信号 瞬时频率 肌肉疲劳 

分 类 号：G804.63[文化科学—运动人体科学]