本研究旨在探討有氧體操中之C類別難度族群項目：科薩克跳、屈體分腿跳、團身跳轉半周三項難度元素之標準與男女選手實施得分之判別；三項難度元素跳躍過程中速度、加速度之運動學比較；騰空動作之運動學表現及騰空高度對跳躍動作之預備下蹲動作及著地下蹲動作之影響。以攝影機進行有氧體操選手（男女共七名）的科薩克跳（Cossack jump）、屈體分腿跳（Straddle jump）、團身跳轉半周（1/2 Turn tuck jump）三項動作影片，爾後將影像資料以Silicon Coach動作分析系統將其動作數位化進行運動學分析。所得數據資料以SPSS 10.0統計分析軟體，以單因子變異數分析、皮爾森積差相關作運動參數之分析，並將影片由具有氧競技體操裁判、教練證之四位國內教練作動作之實施及難度判別。研究結果發現：一、三項難度動作判別所有選手所實施之難度動作皆承認，而實施判別上最易出現之失誤為騰空足姿；二、三項難度動作各關節點於動作過程中發現，上肢與下肢關節間在動作過程中互有影響；三、性別對於騰空動作而言並非為影響表現之因素。四、以不同的動作而言，關節活動角度並非為影響跳躍高度的最主要因素。建議選手在實施三項跳躍動作時，關節活動及維持身體平衡非常重要，訓練過程應加強各關節活動度、柔軟度及核心肌群的訓練，以完美呈現動作並預防運動傷害。

　　The purpose of this study is to analyze the jumping and spring of group C in aerobics gymnastics, including Cossack jump, Straddle jump and 1/2 Turn tuck jump, to discuss about the criteria of the difficulty and score the execution of male and female players, compare velocity and acceleration of the three difficult actions by kinematics, and see how the kinetics and height of air motions influence the squatting postures before and after jumping. We use a video camera to shoot videos of Cossack jump, Straddle jump and 1/2 Turn tuck jump executed by seven male and female players, and digitalize these motions and conduct analyses by Silicon Coach Motion Analysis System. In this paper, SPSS 10.0 was used to analyze the motion parameters in the data obtained above by one-way ANOVA and Pearson Product-moment Correlation Coefficient, and four coaches who came with the qualifications of aerobic gymnastic judging and coaching passes were invited to score the execution and difficulty of the motions in videos. The results were as follows: firstly, all the players successfully performed the three actions and were recognized by them, and the foot in the air is easiest to be mistakenly scored; secondly, of the three actions, we studied how all joint nodes in the process of motions performed and found that upper limbs interacted with lower limbs; thirdly, gender had no influence on the performance of air motions; fourthly, with regards to different actions, angles of joint movement was not the main factor that had an effect on jump height. It is suggested that players should pay attention to joint movement and keep body balance when executing the three actions. Besides, one should foster joint mobility, flexibility, and core training to perform perfectly and avoid sports injury.