I think fitness exercise should be carried out according to one's age and physical condition, which will be beneficial to health. For example, young people with good physical conditions can run, girls can do yoga, boys can make equipment, and the elderly can walk slowly according to their own conditions, preferably from 9: 00 to 10 every morning. At this stage, they can take a walk in the sun outdoors and exercise outdoors from 2: 30 pm to 3: 30 pm.