Speaker: Lin Zhousheng, Associate Chief Physician of Joint Surgery Department of the Second People's Hospital of Guangdong Province

　　After retirement, the elderly begin to shift their focus of life towards exercise. In the morning and evening, we can always see some elderly people dancing in the square, some practicing Tai Chi, and some competing with sports equipment... It is not difficult to find that some behaviors are really too dangerous, such as dancing for three hours at a time, constantly shaking their heads, and even onlookers are worried about the elderly's body. If one is not careful, elderly people will fall into a misconception when exercising, and the more they exercise, the more sick they become.

　　1. Injury to knee due to prolonged square dancing.

　　Aunt Wang, 56 years old, is a bit overweight and suffers from high blood pressure. Since retirement, she has fallen in love with square dancing, and in the past six months, she has become even more obsessed. Every night after dinner, she goes downstairs early and dances with her peers. She always dances until 21 o'clock before returning home.

　　Not long ago, Aunt Wang felt pain in her right knee joint when going up and down the stairs. Later, she even felt pain when walking and softened her legs, making it difficult to stand up after every squat. She rushed to the hospital for examination and was diagnosed with degenerative knee joint disease accompanied by medial meniscus injury. Doctors say it is largely related to prolonged square dancing.

　　The symptoms of this type of patient are basically the same: there is no problem with knee flexion or extension, but the knee pain is obvious when climbing stairs. In severe cases, walking can be uncomfortable, and the pain has eased after a few days of rest. Aunt Wang originally intended to lower blood sugar and blood lipids by dancing square dance, but instead, she broke her knee joint.

　　Why is square dancing easy to get injured? Nowadays, square dance is becoming increasingly difficult, and many body rotation and lower limb twisting movements are usually designed. These movements require high requirements for body center of gravity control, lower limb strength, and stability. Frequent dance time of one or two hours or more means continuous use of joints for a long time.

　　Dancing square dancing is not necessarily better for longer periods of time, and the difficulty level is not necessarily higher. Proper control of time and exercise intensity is beneficial for protecting the knee joints. Do not dance square dance for more than 1 hour each time, and only sweat slightly.

　　Climbing walls and swinging shoulders can easily cause tearing of shoulder sleeves.

　　The rotator cuff tear is one of the common Sports injury of the middle-aged and elderly. There are many such patients in clinical practice. Most of them have a history of shoulder pain, mistakenly thinking that they have shoulder periarthritis and want to relieve it through exercise.

　　When elderly people exercise in the community, they like to frequently perform some lifting movements, including shoulder turns in the horizontal bar or rings, baseball pitches, weightlifting snatches, shoulder swings, wall climbing, and so on. In fact, these actually increase the load on the Shoulder joint, causing or aggravating rotator cuff tears.

　　Periarthritis of the shoulder and rotator cuff injury are two different diseases. Periarthritis of the shoulder is a self-limiting disease that usually improves within six months and no more than two years. If left untreated or exercised in the wrong way, shoulder and sleeve injuries will only worsen. Moreover, there are many diseases of Shoulder joint, not only periarthritis of shoulder, such as subacromial impact, bursitis, rotator cuff injury, glenoid lip injury, etc. These diseases can not be solved by a single Shoulder joint stretching activity, and should be checked by a specialist before corresponding training.

　　3. "Swallow flying" and Sit-up injure the intervertebral disc.

　　Some elderly people will exercise their lower back muscles and perform movements called "swallows flying". 'Swallow flying' is a good exercise posture, but it may not be suitable for the elderly. Because the aging joints and intervertebral discs of the elderly have problems such as joint hyperplasia and Spinal stenosis, excessive extension will intensify the compression and collision of joints, increase the stress of the vertebral arch, cause fractures, and make the spinal canal narrower.

　　Sit-up are also not suitable for the elderly. When doing Sit-up, you should curl up your legs to train your abdominal muscles. The strength is too strong, which has exceeded the fixed force of 150 cattle set by the International Labour Organization for intervertebral discs, which will increase the load on the lumbar spine of the human body and make the degeneration of the intervertebral discs of the elderly more serious.

　　Most middle-aged and elderly people have more or less problems in their cervical vertebra and lumbar vertebra. In addition to osteoporosis, doing Sit-up is easy to cause irreversible damage to their cervical vertebra and lumbar vertebra. In addition, when Sit-up are performed, the head changes greatly. For people with cardio cerebral Vascular disease, it is easy to cause hypertension and accidents.

　　4. Intensive and difficult exercise increases blood pressure.

　　Some elderly people believe that the higher the intensity and amount of exercise, the more beneficial it is to their health, in order to achieve the goal of exercise. However, explosive exercise can cause elevated blood pressure, increased heart rate, and myocardial ischemia and hypoxia. Exercise is about persistence, not speed and intensity.

　　5. Climbing stairs and hiking exercises can increase joint damage.

　　Climbing stairs is listed as an exercise activity by many elderly people in cities. They believe that this type of fitness can be done at home without the need for additional venues or dedicated time, making it convenient and fast. In fact, during the process of climbing stairs, the pressure on the knee joint significantly increases. The repeated impacts and repetitive movements of the knee joint undoubtedly increase the damage to the knee joint and induce knee joint diseases.

　　Climbing is a high-risk event for knee joint injuries, similar to climbing stairs, which can also easily damage the knee joint. The impact force on the knee joint when going downhill is equivalent to 5-8 times one's own weight, exacerbating the damage to the patellar cartilage surface and meniscus.