Generalized muscle soreness and fatigue can be caused by systemic immune response, strenuous exercise, drug reaction, electrolyte disorders and polymyositis and other diseases. 1. Systemic immune response: such as malaria, epidemic typhus, bacillary dysentery and the most common influenza, due to viruses, bacteria and other invasion of the human body leading to systemic immune response, resulting in joints, muscles, synovial soreness, pain, and weakness, etc., generally with the disappearance of pathogens, most of these symptoms can be self-healing. 2. Strenuous exercise: for example, after long-distance running, fitness, playing ball, due to anaerobic muscle movement caused by lactic acid accumulation, causing muscle pain or weakness of the whole body. 3. Drug reaction: sometimes the elderly some special drug reaction, can also be caused, for example, some older people often take a class of lipid-lowering drugs, called statin drugs, this kind of drug will cause the elevation of muscle enzymes lead to rhabdomyolysis, will be manifested as muscle soreness or weakness. 4. Electrolyte disorders: sometimes seen in some electrolyte abnormalities, such as low potassium or low calcium, and in severe cases, it will also manifest as muscle weakness and soreness throughout the body. 5. Polymyositis: it is a kind of widespread inflammatory lesion of skeletal muscle, patients may have obvious symptoms such as muscle soreness and weakness, wasting, difficulty in exercise, etc., and advanced patients may also have muscle atrophy. Patients with symptoms of generalized muscle pain and weakness, which are not relieved after resting or accompanied by other discomforts, should consult a doctor in a timely manner to find out the cause of the disease under the guidance of the doctor, and carry out appropriate treatment if necessary.