目的：本研究主要在瞭解單車騎士的運動參與動機、阻礙因素及持續涉入。方法：採質性研究，以立意取樣方式，採半結構式訪談方式訪談5位具豐富經驗的單車騎士，文件分析，以及參與觀察方式觀察其中2位騎士的運動參與行為6週。所得資料經開放性、主軸性及選擇性編碼，持續加以比較、整理及分析。結果：單車騎士運動參與動機包括交際涉入、體適能及情緒補償。其阻礙因素包括構性阻礙，個人性阻礙及人際性阻礙；持續涉入的因素包括自我調整、自我挑戰及自我滿足。結論：單車騎士主要為培養體能，增進人際關係及紓解生活壓力等因素參與運動。常因家庭、工作、親友互動、天候及器材設備等因素阻礙其運動。採取理性思考、積極態度、克服障礙、投入熱情、自我期待等方式可幫助單車騎士持續涉入。

Purpose: The purpose of this study was to explore the participation motivation, barrier factors, and enduring involvement in bicyclists. Methods: Based on the qualitative methods, five experienced bicyclists were interviewed by judgment sampling and using semi-structured interview, documents analysis, and two experienced bicyclists were observed their actual participation behaviors for six weeks by participation observation. All of the data were rearranged, induced, compared, and analyzed by open coding, axial coding, and selective coding. Results: The results of this study indicated that the participation motivations of bicyclists included social involvement, physical fitness and emotional compensation. The barrier factors included structural barriers, interpersonal barriers and social barriers. The enduring involvement included self adjustment, self fulfillment and self challenge. Conclusion: The main factors of riding for bicyclists were to promote their fitness, social relationships, and reduce stress. They were usually constrained by family, work, social interaction, climates, and equipments. By reason thinking, positive attitude, overcome barriers, enthusiasm, and self expectancy could enhance the bicyclists’ enduring involvement.