研究目的：本研究的目的有二：（一）探討無損傷或病變之足月兒的跨步動作與行走達成年齡的相關性，以及（二）探索可能和行走達成有關之影響因子。研究方法：本研究包括20名足月兒，於年齡7個月開始每兩個月接受跑步機跨步動作評估（速度0.1與0.2公尺／秒）直至行走達成為止，跨步動作以Peak Performance動作分析系統記錄與分析，可能之影響因子包括身體成長、皮脂厚度、與粗動作功能。結果：嬰兒之平均行走達成年齡為11.4個月（標準差1.2個月，範圍10-14.3個月）。Cox's比率危險單變項迴歸分析顯示，年齡9個月時的跨步動作具較長之著地期、較大之著地時膝關節伸直角度、以及兩腳間較對稱之著地期和離地期，則明顯有利於較早之行走達成(p<0.05)。另外，年齡7個月時較小之二頭肌與肩胛下皮脂厚度、較低之全身脂肪比率、與較高之粗動作分項分數和總分；以及年齡9個月時較小之恥骨上皮脂厚度、與較高之粗動作站立分項分數，亦明顯有利於較早之行走達成(p<0.05)。結論：本研究的結果顯示，足月兒於行走達成前呈現逐漸統整之跨步動作，而且其行走發展的過程相當複雜，可能和多系統的變化有關。

Purposes: The purposes of this study were to examine the relation between stepping movements and age of walking attainment in full-term infants who had no known impairments or pathology, and to explore the potential influencing factors for walking attainment. Methods: Twenty full-term infants were prospectively examined for stepping movements at a two-month interval from 7 months of age until walking attainment. Infants were supported stepping on a treadmill at 0.1 and 0.2m/s speeds, and the stepping movements were recorded and analyzed using Peak Performance Motion Analysis System. Potential influencing factors included physical growth, skin fold thickness, and gross motor function. Results: Infants attained walking ability at a mean age of 11.4 months (SD 1.2 months, range 10-14.3 months). Cox's proportional hazards univariate regression analysis revealed that a long stance time, a large knee extension at foot contact, and a symmetrical interlimb coordination pattern in the stance and swing time in stepping movements at 9 months of age were associated with an increased rate of walking attainment (all p<0.05). Furthermore, a small skin fold thickness at the biceps and subscapular areas together with a low percentage of total body fat and a high motor subscale and total score at 7 months of age; and a smallsk in fold thickness at the supra-iliac area together with a high standing subscale score at 9 months of age were also associated with an increased rate of walking attainment (all p<0.05). Conclusions: Our findings indicate that full-term infants demonstrate gradually organized stepping movements prior to walking attainment. The developmental process of walking appears complex that may relate to changes in multiple subsystems.