Basically, everyone is born with a pair of well-designed, high-functioning knee joints. Of course, the quality of the joints varies from manufacturer to manufacturer. If you happen to have the quality of a Mercedes Benz, the proper care and exercise, and the control system of an athletic brain, then you could be Beckham. But if your knee joints are not of good quality and you have some problems from time to time, then you need to pay attention, knee joints may only be a substitute for you. Understand your knee joint, appropriate use of him, standardized maintenance exercise him, he will bring you greater joy in life. The knee joint is the largest and most complex joint in the human body, but also the most vulnerable to injury during exercise. The knee joint consists of the upper thigh bone (femur) and the lower leg bone (tibia), there is also a small bone with the knee movement on the surface of the femur sliding, called the patella, patella on the human body’s most powerful muscle – quadriceps, down to the tibia anterior side of the tibia, muscle contraction can straighten the knee. By the way, the punishment of amputation that Sun Bin received during the Warring States period was the power to remove the patella so that the knee joint could no longer be straightened. Around the knee joint there is a strong ring of ligaments connecting the femur and tibia to stabilize knee movement. The strength of the ligaments in the human body is close to that of a steel cable of the same thickness, and can withstand hundreds of kilograms of force during movement. The knee joint is stabilized by the following four main groups of ligaments: 1. The medial collateral ligament: connects the femur and tibia on the inside of the knee joint, preventing the knee from turning out too much. 2. Lateral collateral ligament: connects the femur to the tibia and fibula on the lateral side of the knee to prevent the knee from over-turning. 3, Anterior cruciate ligament: connects the femur and tibia diagonally in the center of the knee joint, which can limit the forward sliding and rotation of the tibia. 4. Posterior cruciate ligament (PCL): travels in the opposite direction to the ACL and restricts backward sliding and rotation of the tibia. Between the joint contact surfaces there is cartilage covering the surface of the articular bones and two crescent-shaped structures called menisci, which are used to cushion the impact between the articular bones. The knee joint has both weight-bearing and movement functions. Daily weight bearing has a lot to do with your weight. For every pound you are overweight, you have to carry six times as much weight in your knee area. For example, if you are five pounds overweight, your knees have to carry an additional 30 pounds. You wouldn’t want to set up a big truck on the tires of a small car! The knee joint has the function of extension and some rotation, but extreme rotation can damage the meniscus extensor cruciate ligament, which is the reason why meniscus and cruciate ligament injuries often occur in soccer players. People who have been engaged in heavy physical labor and strenuous bouncing sports for a long time can easily injure the knee joint. The main symptoms include synovitis, cruciate ligament tears, meniscus injuries, cartilage injuries and more. People whose knees are often irritated by cold are prone to chronic knee diseases such as chronic synovitis and so on. In order to maintain the health of the knee joint, I have some suggestions as follows: 1. Keep slim (1) Weight control can reduce the pressure between the articular cartilage and bone, which can delay the occurrence of arthritis in old age. (2) Maintaining a slim figure can reduce the chance of ligament damage during the same exercise program. (1) Many knee problems are caused by overly tight ligaments or muscle imbalances. Regular joint flexion and stretching exercises can avoid joint pain. (2) Knee stretching can relax the knee joint, thus avoiding patellofemoral arthritis and iliotibial bundle syndrome. (3) Straight leg raise as well as extreme knee flexion stretching exercises can prevent knee injuries during exercise. 3, smart exercise If you have knee pain from time to time, choose swimming or water exercise programs. Buoyancy in the water can share the pressure of weight on the joints. If you don’t have the conditions or don’t like water sports, at least avoid sports that involve strenuous weight-bearing and rotation of the joints, such as basketball, badminton, tennis and bouncing. Be good at listening to your body’s advice, for example, if the joints ache when exercising, it means that he is hurt, then it is best to stop exercising immediately. If you feel fatigued, then you also need to stop exercising, because it is easy to get injured if you continue. Pay attention to the posture of walking and labor, do not twist your body to walk and work. Avoid squatting for a long time, because when squatting, the weight of the knee joint is 3 to 6 times your own body weight, squatting at work (such as car mechanics, sandblasters) is best to change to a low sitting position (sitting on a small stool), sitting and standing for a long time, but also to change the position often, to prevent the knee joint from being fixed in a position and exerting too much force. 4, keep warm. When the knee joint encounters cold, the blood vessels contract and the blood circulation becomes poor, which tends to aggravate the pain, therefore, attention should be paid to keep warm in cold weather, and wear knee pads when necessary to prevent the knee joint from being cold.