Intervention methods
lower extremity muscle strength
Subjects in both groups received calcium routinely as the basic anti-osteoporosis treatment (vitamin D calcium chewable tablets with 100 IU of Vit D, 200 IU/day).In control group, subjects performed routine fall prevention exercises under the leadership of an instructor, including medium-intensity aerobic gymnastics and apparatus exercises, with 50 min each time, 3 times per week, lasting for 12 months. The goal is to achieve core muscle training, lower extremity muscle strength, balance and gait function training.In VR group, a VR rehabilitation training system (Nanjing Moxun Company, Motion2.0) was used for training. The subjects wore eye masks and were received 3 kinds of VR sports games: skiing, diving, and running. The training regimen was 3 times per week, 50 min each time (including 5-min of warm-up exercise, 40-min of VR sports game training and 5-min of organized exercise), with total training period of 12 months.