本研究旨在瞭解中老年族群參與鐵人三項運動過程中自我實現、心流體驗與幸福感之研究，採重複抽樣方式於2014年間參與鐵人三項的中老年族群為研究對象進行調查，共收取有效問卷共152份。經t檢定、卡方檢定、皮爾森積差相關以及多元回歸分析資料後顯示：一、在心流體驗中，有無規律運動與參賽次數有顯著差異；幸福感構面中，運動習慣呈現顯著差異；自我實現構面來說，除了參賽次數之外，不同的人口變項對自我實現均有顯著差異。二、心流體驗、幸福感、自我實現之關係中，心流體驗與幸福感為顯著正向相關，自我實現對幸福感也有正向影響，但心流體驗與自我實現並無顯著相關。三、在中老年人參與鐵人三項過程中，心流體驗與自我實現對於幸福感均有正向影響。根據結果，參與鐵人三項運動的中老年族群有固定的運動習慣，並會長期參與此項運動，更藉由參與過程，達到心流體驗、自我實現，並產生幸福感受，讓中老年族群因此達到身體健康、心靈健康與社會適應，也就是達到成功老化的目的。

The purpose of this study was to understand the middle-aged and elderly participants in self actualization, flow experience and well-being during the process of triathlon. The purposive sampling method was adopted for data collection and valid questionnaire survey were collected for total of 152. Data was analyzed through t- test, chi-square test, Pearson product moment correlation and multiple regression analysis. Result of this study indicated first, in flow experience, between regular and non-regular exercise and competition number of times had significant difference; In Well-being aspect, the exercise habits showed significant difference; In gaining self actualization, except competition number of times, between different demographic variable and self actualization showed significant difference. Second, three of the self actualization, flow experience and well-being relationships, between flow experience and well-being had positive correlation, between well-being and self actualization had positive correlation, but Flow experience and self actualization has no significant correlation. Third, during the process of the middle-aged and elderly participating triathlon, when both the Flow experience self actualization positively influence well-being. In conclusion, participating triathlon in the middle-aged and elderly have regular long-term exercise habits. By participating in the process gained the self actualization, flow experience and well-being, therefore lead the middle-age and elderly to achieve good health and spiritual health and further success in aging purpose.