Author(s): FUBAIHUI, W., Institution: CHINA INSTITUTE OF SPORT SCIENCE, Country: CHINA, Abstract-ID: 426

Introduction
The life expectancy of Chinese population is increasing continuously, and whether the proportion of healthy life is increasing simultaneously has become the focus of attention. Healthy life expectancy is an important index to measure life in old age. We aim to estimate the impact of physical exercise on healthy life expectancyof the elderly in China.
Methods
Based on the data from Chinese Longitudinal Healthy Longevity in the 2002-2018, We first calculate the healthy life expectancy of the elderly in China, and then use channels to test the influence of physical exercise on healthy life expectancy of the elderly. We first estimate the regression coefficient of physical exercise on healthy life expectancy, then add channel variables affecting healthy life expectancy and further calculate the contribution of channel variables to healthy life expectancy. Finally, the difference in healthy life expectancy between the elderly with or without exercise habits matched by propensity score.
Results
The influence of physical exercise on the healthy life expectancy of the elderly is always significant. The healthy life expectancy of the elderly with physical exercise habits is 3.45 years longer than that of the elderly without physical exercise habits, and the proportion of healthy life expectancy is also 9.5% higher. The contribution of smoking, drinking, physical exercise, social interaction and medical service accessibility to healthy life expectancy is 1.05%, 1.05%, 3.16%, 2.11% and 1.05%, respectively, and the total contribution is 5.26%.
Discussion
The relationship between physical exercise habits and healthy life expectancy/proportion of the elderly is stable. The healthy life expectancy of the elderly with exercise habits is longer than that of the elderly without exercise habits, and the proportion of healthy life expectancy is significantly higher than that of the elderly without exercise habits. Subdividing the years of exercise habits and further considering the health level in the previous period, the healthy life expectancy of the elderly who do not exercise (especially in the state of not exercising in both periods) is the shortest. The healthy life expectancy of the elderly with short exercise habits and no medical insurance and chronic diseases is at a disadvantage. Health behavior (smoking and drinking), social participation (participation in various activities) and access to timely medical services are channel variables of physical exercise affecting healthy life expectancy. Social participation behaviors such as physical exercise and other activities have a relatively large contribution to healthy life expectancy and its proportion of the elderly. Personal health behavior and medical services have a relatively small impact on it. The healthy life expectancy of rural female elderly and urban male elderly is the shortest among the elderly with exercise habits. This paper further confirms the positive effect of physical exercise