Muscle soreness after exercise and is not a good thing has nothing to do with, in general, is a normal physiological phenomenon, a few may be a pathological injury. 1. physiological phenomenon: normal people exercise process will appear muscle anaerobic metabolism two, anaerobic metabolism muscle will produce a large number of lactic acid, oxygen free radicals and other metabolic products, and muscle fiber tearing. The metabolic products, especially lactic acid, will stimulate the surrounding nerve roots in the process of discharging out of the body, appearing after exercise muscle soreness, which is a normal physiological phenomenon of the body. 2. Pathological injury: If the amount of exercise is too large or the way of exercise is not right, it may cause muscle rupture, or even rhabdomyolysis, when rhabdomyolysis, intracellular substances such as myoglobin, creatine kinase, etc. are released into the extracellular fluid and blood circulation, and muscle soreness will also occur. Rhabdomyolysis may lead to acute, life-threatening renal failure. If the patient has severe symptoms of muscle soreness after exercise, or if the symptoms persist without improvement, he or she should go to the hospital promptly for treatment.