The muscles of the arms keep jumping: 1. It may be local motor epilepsy, which causes involuntary contraction of the body’s arm muscles. It is mainly caused by abnormal discharge of brain cells and the inability of the central nervous system to suppress its impulses. 2, there is also benign myofibrillation caused by fatigue, anxiety, insomnia, excessive exertion and other factors, manifesting as involuntary contraction of arm muscles. The symptoms can be relieved by local heat application and rest. If this happens and there is no relief within a short period of time, you must go to the hospital in time to improve the relevant examination, and then choose further treatment methods to get effective relief of the symptoms of arm muscle jumping as soon as possible.