| Objective: Based on the technical analysis of the present difficulty in Wheel Spin, this paper will analyze the structure of technical movement more correctly and establish the concept of Wheel Spin technique to make up the shortcoming which brought by people's perception, consequently estimate the technique. This paper will enhance the action more perfect and the consequence of the turning more smoothly. For the purpose of improving the quality of athletes'movement in freestyle slalom artistic Skating and the integrity of the entire exercise, the author sets this study to promote the scientific training in freestyle skating movement. The author also sets a goal to seek for providing a strong theoretical basis for guiding the practice offering an objective evaluation criterion for continuous improvement of the contest rules and to fill the technical gaps in freestyle skating field at home and abroad.Main methods: With the utilization of two Sony digital video cameras which are made in Japan, we take photos for the direction of movement about the experimental subjects, respectively from the side and positive side to precede fixed point, fixed-focus and the synchronized manner. The main axis angle between the two aircraft is nearly 90°and the frequency is 50 frames/ sec. In addition, we also take pictures for the complete technical movements of single-wheel rotation and analyze the data of three-dimensional image. Findings: (1) From the view of the action in quality, the higher quality the edge spins, the more laps it whirls. Likewise, the speed spins smoothly, the rhythm goes clear. In the process of rotation, the displacement of the focus has no fluctuation and it moves faster in X-axis; the angle between lower limb non-supporting leg hip joint and knee changes regularly. Knee lifting is the most obvious way. Orderly staggered displacement of upper shoulder, prior to displacement of lower extremity to whirl for the research subject and will provide reference for the future establishment of such action technology model. (2) From the time point of view, the time of spinning increases with the sum of the laps after the competition of study. The object is the outer edge switch to single-wheel rotation. The displacement of the focus in X-axis decreases. When it spins to the fourth laps, the limiting value of minimum reaches 79.36cm. However, the displacement of the focus in Z-axis has two obvious fluctuations, especially the fourth laps. At that time the limiting value of minimum comes to 109.08±15.53cm. When the joint angle goes to the third laps, the negative peak between the left and the right is obviously bigger than the joint of the left hip. Body lean forward and shoulders of upper limb fall down in order to coordinate the balance of the centre gravity of the body. It will be not conductive to the control of spinning rhythm. (3) Outer edge before the transfer spins one quarter lap, which is obviously less than the outer edge switch. However, the rotation time on average is near to the outer edge which can reach 0.65 sec/c. The single circle cost less and less time. On the contrary to the other three ones, the speed of focus in X-axis spins at least 156.48cm/s. The vertical speed of focus in Z-axis reaches the -40.72cm/s at the first lap and quickly slow down to the minimum of -0.31cm/s. When it comes around the second one, body leans forward at the same time the position of shoulders moves up as far as possible to maintain the balance of body. Squatting is needed and the angle of the knee joint is at least 83.95°or the hip reaches the maximum 163.95°. The posture of body impacts rotation effects directly. (4) Within the edge after the turning is a kind of rotation mode, which the subject of this study spins the weakest. That only spins two laps, costs 0.8 seconds on average and the speed is rather slow. From the X-axis direction, the displacement which is 113.04cm is large at the first lap. It affects the distance directly. The initial speed of rotation is also fast, which goes to -176.78cm/s. There is no displacement in Y-axis and the rotating torque is tiny. The outer edge switch just rotates two laps. The angle of Knee joint becomes smaller at the upward movement and turning round. There is no obvious change in hip when the leg is held. Without the action of lifting knee, movement of shoulders is small and the distance between the body axis and axis of rotation is tiny. Adding to the poor balance sense, completing this task for the subject of this study is the most difficult thing.Suggestions: Firstly, to strengthen the exercises of the special lower extremely muscle strength and body balance. Secondly, to emphasis technical details of the training in technical spin class .Thirdly, to enhance flexibility training of ankle and support the training of strength.
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