對老年人口而言，規律運動行為可以減輕慢性疾病的惡化，也是維持身體功能並延緩老化的重要方法。本文建構老年人口參與運動或身體活動行為的理論模型，進一步利用台灣營養健康狀況變遷調查2004~2008中65歲以上之樣本，檢視人口特質、經濟條件和健康狀況等因素的影響效果。考量自覺健康狀況可能存在內生性問題，提出以認知功能評量和有無三高病史作為工具變數，並採用兩階段的估計方法。分析結果顯示，年紀達80歲以上時，規律運動比例降低；若自覺健康狀況較好，落實規律運動的比例較高；而經濟條件和居住地的人口密集程度則分別對男性和女性老年人的運動行為具有顯著效果。

Chronic diseases are common health problems for elderly people and account for the majority of the top 10 causes of death in Taiwan.Physical activity has been regarded as a critical pathway for delaying aging and promoting the health of elderly people. This study constructed a theoretical model for elderly people’s physical activity. Its empirical analyses discussed influential factors by using the 2004~2008 Nutrition and Health Survey in Taiwan.
Ordinary least squares (OLS) estimates indicated that physical activity in elderly people was correlated with age and perceived health condition. To solve the endogeneity problem of perceived health, this study used cognitive function and history of chronic illness as instrumental variables and adopted the two-stage least squares (2SLS) method. The 2SLS results indicated that cognitive function had a positive effect on perceived health condition; furthermore, the estimated coefficients of perceived health condition were higher than those estimated using OLS. Overall, elderly people aged less than 80 years and with a higher perceived health status had a higher probability of implementing physical activity.