本研究目的為透過運動學、力學、生理負荷與主觀費力程度等評估，探討自行車騎 乘姿勢與騎乘舒適度之關係。二十位健康年輕人自願參與實驗，平均年齡為 24.6 歲 (SD=0.1)，所有受試者均無肌肉骨骼與神經傷害或病史。在實驗前，受試者在可調整把 手與坐墊高度的市售自行車上，調整並選擇主觀最適把手與坐墊高度。所有受試者隨機 在九種不同騎乘姿勢(3 把手 ×3 坐墊高度組合)下，以固定阻力；固定速度(每分鐘80 轉)轉連續踩踏自行車一小時。超音波三度空間動作擷取系統 (Zebris Medical GmbH, Germany) 用來收集手腕橈尺偏、手腕屈伸、軀幹前傾、髖關節內收外展與膝關節屈曲 等關節角度。身體壓力量測系統 (Body Pressure Measurement System, Tekscan, U.S.A) 用 來量測手部壓力中心路徑、把手力量、臀部壓力中心路徑與坐墊力量等力學資料。心搏 儀 (Polar RS-800, Kempele, Finland) 用以量測休息與運動心跳作為生理負荷指標。主觀 費力程度評比(Borg CR-10) 用以評量身體六個部位包括: 手腕、上背、下背、臀部、膝 部與腳踝的費力程度。 結果指出，當騎乘姿勢為較低把手與較高坐墊高度時，有較大的手腕尺偏、手腕伸 展、軀幹前傾與髖關節外展的關節角度。此外，低把手高坐墊也會也較高的把手力量、 更多的主觀費力程度在手部、背部與腳踝及較高的生理負荷。當騎乘姿勢為高把手低坐 墊姿勢時，有較多的手腕屈曲角度、較多的臀部壓力中心位移路徑、較小的軀幹前傾與 較多的臀部費力程度。瞭解騎乘姿勢對騎乘舒適度的影響，將可以提供在自行車騎乘舒 適之把手與坐墊調整的參考，進一步避免自行車相關慢性肌肉骨骼疾病的發生。

This study aims to understand the relationship between riding posture and cycling comforts by assessing the kinematics, kinetics, physiological loading and subjective perceived exertion rating. Twenty young adults with mean age 24.6 years (SD=0.1) were recruited to participate in this study. A commercial city bike with the adjustable handlebar and saddle had been set on the indoor cycling stands. All subjects were asked to ride randomly with 9 different postures (3 handle ×3 saddle heights) for continuous one hour. A 3-D motion analysis system (Zebris Medical GmbH, Germany) was used to collect the kinematic data. The body pressure measurement system (Body Pressure Measurement System, Tekscan, U.S.A) was applied to measure the pressure distribution, force and displacement of centre of mass (COM). A heart rate monitor (Polar RS-800, Kempele, Finland) was used to record the heart rate as the physiological loading. Moreover, a subjective perceived exertion rating scale (Borg CR-10) was used to assess subjective comfort around the body regions. The results of this study indicated that the lower handlebar with higher saddle cause greater ROM in wrist-ulnar deviation, wrist extension, trunk flexion and hip abduction. It also reveals more force on hand region, more discomfort around hand, ankle and back, and higher physiological loading. While cycling with higher handlebar and lower saddle, it has more ROM in wrist flexion, more body displacement on buttock region, little trunk forward, and more discomfort rating in buttock region. For handlebar and saddle adjustment, the considerations of body dimensions and characteristics, the relationship between handlebar and saddle heights might improve the cycling comfort and diminish musculoskeletal injury.