Every year in the summer, some middle-aged and elderly people get knee pain and sometimes swelling in the knee joint, which causes inconvenience in daily life. What is it? The knee joint is a large and complex flexor joint in the body, which is subject to high stress and has a stable yet flexible structure. Knee pain occurs from time to time, and this pain is often ignored or arbitrarily thought to be a condition such as arthritis. In fact, there are many causes of knee pain. Most joint pain in daily life is not caused by trauma, but by prolonged exposure to cold and large temperature differences. Especially at the time of alternating warm and cold temperatures, low temperatures or huge temperature differences can cause muscles and blood vessels to contract. This causes joint pain. How can we avoid knee pain and discomfort in the hot summer? Should be noted from the following aspects: a. Avoid cold wind: electric fans, air conditioning is an effective tool for people to cool, if overuse, the temperature is too low, or use too long, will make the wind and cold of the evil invasion of the knee joint, so that blood stagnation, resulting in knee pain, numbness, swelling and other ailments. Second, avoid cold water bath: hot summer climate, if the body is hot and sweaty when the rush into the cold water bath or cold water shower, will make the cold damp evil invade the knee joint, inducing knee joint pathology. Avoid cold drinks: If you drink too much cold and eat too much cold, you will damage the spleen and stomach, which will reduce the function of the spleen and stomach in transporting water and dampness, so that the knee joint will lose its warmth and the cold dampness will stay in the knee joint, which will aggravate the disease. If the cartilage of the knee joint has degenerated and worn out, try to avoid climbing mountains, strenuous activities and other forms of exercise that will add weight to the joint, and choose activities such as swimming and slow walking. If you have knee pain and discomfort, the first thing you should do is to keep your knee as warm as possible by applying heat; the second thing you should do is to reduce the amount of exercise and, if necessary, to lie in bed so that the joint can rest. If the above methods do not make the knee pain better, then it is necessary to go to the hospital to clarify the cause.