Exterior electrode can derive in the synthetic potential of all muscle activity , but cannot differentiate potential of single block sarcous 表面电极可以导出深处全体肌肉活动的合成电位，但不能分辨单块肌肉的电位。
2.
Liver is damaged or bile is excreted not when free , fat of the choline in blood is enzymatic decrease , influence nerve , sarcous is normal physiology function 肝脏损害或胆汁排泄不畅时，血中胆碱脂酶减少，影响神经、肌肉的正常生理功能。
3.
Insert needle electrode the muscle that is about to check to be able to derive potential of individual sarcous movement , reason this law is relatively commonly used 将针电极插入欲检查的肌肉可以导出个别肌肉的动作电位，故此法较为常用。
