I. Self-test of knee joint wear The life span of a joint is mainly related to human genes, trauma and the amount and intensity of exercise. Knee joint in the long-term use, whether the problem, what problems, you can self-test by the following methods. 1. Single-leg squat self-test method Method: Stand on one leg, squat, and knee joint into 90°. If the knee joint can not do 90 °, or the knee joint into 90 ° before the pain or instability, indicating that your knee joint cartilage has degraded, wear. 2, 30 seconds to sit up test method International there is a self-test joint method, called 30 seconds to sit up test method. Method: Sit on a 43 cm high stool, stand up as fast as possible, then sit down, and see how many times you can do it in 30 seconds. This action is to measure the function of the knee joint; the second is to measure cardiorespiratory function. Generally people over 60 years old need to do this test. Second, the warning from the knee joint Third, how to protect your knee joint How to protect the knee joint, experts summed up the four words, called “stretching and stretching”. It can strengthen the quadriceps, increase muscle strength and improve knee stability. Method: Lie on the bed, both legs relaxed, first lift the left leg, hook the foot up, leg straight suspension, adhere to 3 ~ 4 seconds, put down. Then change the right leg lift, hook the foot up, leg straight suspension, left and right legs to do count 1, do 10 ~ 15 times. Usually exercise as little as possible to do deep squats, some of the knee joint is too flexed to avoid the action. Fourth, out of the joint exercise common misconceptions 1, squatting against the wall Now one of the most popular exercise methods online squatting against the wall, can really exercise our knee joints? Squatting against the wall this action, that is, back against the wall, feet together, thighs and calves bent into 90 °. I think this method is a double-edged sword, in the exercise of muscle while also testing the muscles, causing a lot of stress on the joints. The older and heavier the person, the more dangerous it is to do this movement. This action is only suitable for young, no problems with the joints, lighter weight people. 2, fitness equipment Fitness equipment in small communities can also cause serious damage to the joints of the human body if used improperly. According to the degree of wear and tear on the knee joint in order: (1) rowing machine. Mainly exercise back and arm strength, relieve low back pain, the impact on the knee is not great, you can use it to exercise the knee. (2) fitness walking machine. Mainly used to exercise the legs, waist, abdominal muscles and cardiorespiratory function. It mainly relies on thigh strength to make force, can help the muscles around the knee joint exercise, and did not cause too much pressure on the knee. Can be properly used. (3) Elliptical machine. Its main function is to increase the abduction, adduction and rotation of the hip joint inward and outward. It is mainly used for rehabilitative training of joint range of motion after fracture and nerve injury and for restoring muscle strength after muscle injury, which puts greater pressure on the knee, and it is recommended not to use the elliptical machine for knee exercise. (4) Cycling machine. It is like riding a bicycle, and practiced to strengthen the muscle strength. During pedaling, the knee has a large extension and flexion, so that the knee joint maintains a degree of mobility. It is suitable for people who have had joint disease and have had joint replacement surgery, and can be used as an auxiliary device to restore joint activity.