Muscle soreness after normal exercise often does not appear immediately after exercise, but appears on the second or third day and gradually relieves after 2-3 days. If muscle soreness is caused by lactic acid accumulation during exercise, it should peak during or immediately after exercise. How can it appear after the next day? What is the cause of this muscle pain? How should it be mitigated or prevented? This kind of muscle soreness, which usually appears 24 hours after exercise, is called "delayed muscle soreness" in sports medicine. The pain peaked 24-72 hours after exercise and basically disappeared after 5-7 days. In addition to soreness, there are muscle stiffness, mild tenderness and severe muscle swelling, which hinder activities. Delayed muscle soreness may occur in any skeletal muscle after strenuous exercise, especially after long-distance running. Long-distance runners will have pain in the extensor and flexor muscles of their hips, thighs and calves, especially at the distal end of the joint between muscles and tendons. After extreme exercise in hot summer, besides muscle pain, there will be symptoms such as dehydration, low calcium and low protein. The exact cause of this muscle pain is not completely clear. Most people think that excessive use of muscles will cause muscle soreness, the reasons are: 1, the tension and elasticity of muscles increase sharply, which can cause physical damage to muscle structural components. 2. With the increase of metabolism, the toxicity of metabolic waste to tissues increases. 3. The neuromodulation of muscle changes, causing muscle spasm and pain. How to prevent it? 1, the exercise schedule should be reasonable. After a period of exercise, the symptoms of muscle soreness were alleviated. And be single-minded. For example, downhill exercise can relieve muscle pain caused by downhill exercise after a period of time. 2, local warm rubbing medicine. Washing with warm water after exercise can relieve muscle soreness. Topical oil, ointment or liniment can also relieve pain. 3. Stretching muscles can relieve soreness. Stretching muscles can accelerate the relaxation of muscles, relieve antagonistic muscles and help the recovery of tense muscles. This kind of muscle stretching exercise also lays a foundation for preventing strain during exercise. 4. Make preparations and organize activities during exercise. Adequate warm-up activities and reasonable finishing exercises are helpful to prevent or relieve muscle soreness. The main methods to prevent and relieve muscle soreness are: (1) hot compress: put the towel on the sore muscle after soaking it with hot water, and replace it immediately when there is no heat sensation. Apply 15 minutes or more each time, 2-3 times a day. Hot compress can dilate the blood vessels of sore muscles, improve blood circulation, relieve muscle spasm, and is beneficial to the regeneration and repair of damaged tissues. (2) Electrotherapy: Electrical stimulation therapy and intermittent current therapy are mostly used. (3) Massage: Kneading technique is often used, with four fingers together, thumbs apart, hands pincer-shaped, palms and fingers tightly attached to sore muscle skin, thumbs and four fingers relatively hard to lift the muscles slightly upward and make a rotation movement towards the heart. It can also be combined with acupoint massage. After determining the action point, press the action point with the middle finger and thumb pulp. Press and rotate your fingers continuously and slowly. Massage at each action point for 1- 1.5 minutes. (4) Oral vitamin C: Taking vitamin daily is about twice as much as the daily requirement, and taking it continuously for 30 days can prevent or at least relieve muscle pain after exercise. Its mechanism of action is still unclear. (5) Stretching exercise: Stretching exercise not only helps to prevent delayed pain, but also relieves the existing delayed pain. But when using stretching exercises, it should not be too sharp or too intense. Excessive force may further damage connective tissue. Static stretching in stretching exercise is a simple and effective method, and the time should not be too long, and there should be a rest in the middle to facilitate smooth blood flow. (6) Acupuncture: Moxibustion therapy is to burn or smoke sore muscles with moxa sticks or moxa sticks. Acupuncture has a significant effect on relieving delayed pain. Acupuncture at related acupoints or oblique needles (along the direction of muscle fibers) by hand makes the acupoints of muscle A ache. You can also use electroacupuncture therapy. When there is delayed pain, or when there is no delayed pain after exercise, acupuncture can be used to prevent delayed pain. There are also physical therapy, water therapy and drug therapy. Actually, it only takes two days.