Sports medicine divides muscle soreness caused by exercise into two types: one is that the pain appears immediately after exercise, but soon disappears, which is called acute muscle soreness. The other is that it appears only a few hours or one night after exercise, accompanied by fatigue and fatigue, and even muscle spasm, stiffness and other symptoms. This kind of muscle pain disappears slowly, and it often takes 3 ~ 4 days or even 6 ~ 7 days to fully recover. This symptom is called delayed muscle pain or fatigue after exercise. We often say muscle soreness mainly refers to the latter, that is, delayed muscle soreness. There is a clear difference between muscle soreness and strain. In fact, muscle soreness is a normal and positive physiological manifestation. People often have obvious muscle soreness and discomfort after strength training or an unsuitable exercise (excessive exercise or new exercise, etc.). ). These symptoms will disappear naturally after a period of rest, and when you do the same exercise again, the symptoms of muscle pain will be obviously alleviated or not produced. Muscle strain caused by exercise is different. Muscle or ligament strain can cause large-scale pathological changes of skeletal muscle, such as cell degeneration and cell necrosis, which not only affects continuous exercise or training, but also may bring more serious consequences. Self-identification of strain and muscle soreness Muscle and ligament strain will suddenly appear because of a harmful action, and muscle soreness will gradually increase. There is a way to distinguish the two: muscle soreness can be relieved by pulling, but if it is a sports injury, pulling will aggravate the pain. In short, muscle soreness and muscle (or ligament) injury after exercise are completely different. Muscle soreness can be relieved by rest, traction and massage. Muscle (or ligament) injury must be solved by medical means.