1, exercise methods (1) walking: intensity: 2-3 laps per time (400 m per lap), 80-90 steps / min. Technical requirements: head up, chest up, straight waist, limbs swing freely, the two arms just force forward swing, attention mainly on the respiratory system, the thorax and shoulder girdle activities. (2) running: intensity: 2 to 3 laps each time (exercise intensity reference “heart rate = l70 an age”). Technical requirements: upper body slightly forward, head natural. Torso abdominal pull back, two arms natural coordinated swing, two legs hard stirrups swing, attention is mainly on the legs of the stirrups and lumbar spine feeling of force. (3) fitness exercises: cervical spine exercise methods: and the item to compete with the force, the neck to compete with the force, before reaching out to explore the sea, looking back at the moon, etc.; upper limb exercise methods: left and right open bow, hands lifting the tripod, bending brachial paddle, push-ups, etc.; waist and back exercise methods: according to waist turn waist, insert palm climbing feet, twist waist turn body, supine two head up, stretch back bridge, etc.; leg exercise methods: knee, turn knee, swing kick, leg lift, change step, half boarding jump, etc.. Intensity: the duration of the exercise is l5-20 min each time Technical requirements: the direction of the movement is accurate, the amplitude is in place, the muscles being moved are clear, and the attention is focused on the part being exercised. (4) Taijiquan: 24 simplified Taijiquan and Taiji Push Hands training, mainly Taiji Push Hands training at the later stage. Intensity: each training time is l5-20 min. Technical requirements: mainly control the locomotor balance of the center of gravity, the action of the waist as the axis, waist as the master, training with the intention to guide the qi and blood running around the body. Focus on the waist, especially for Taiji pushing hands training to pay attention to the feeling of the lumbar spine. The following exercise frequency: the number of times per week to participate in sports and exercise for 3-5 times, not less than 3 times 2, exercise principles (1) the prevention of osteoporosis exercise to the middle-aged and elderly, before exercise shall be routine physical examination and motor function test to ensure safety (2) exercise should avoid too much explosive, power exercises and breath-holding action, the intensity of exercise should be gradually increased from small too To prevent sports injuries. (3) as far as possible in outdoor sports. (4) during exercise, to enhance dietary nutrition, especially pay attention to animal food calcium supplementation should be under the guidance of a doctor when necessary, appropriate supplementation. (5) To maintain a high bone mass or delay the loss of bone mass whether young or middle-aged or elderly, it is necessary to persistently adhere to exercise, improve interest in exercise and develop exercise habits. (6) Regular physical examination, according to the results of the elm check and exercise feeling at any time the whole, in order to ensure reliable exercise effect.