The movement types of attention focus instruction for stand-jumping from the perspective of motor coordination
目的: 動作協調型態是近年來動作控制領域重要研究議題，過去研究指出外在注意力焦點指導因跳遠「開始瞬間」動作不同於內在注意力焦點，但兩組間各肢段動作協調型態是否有差異尚未清楚，本研究從單一運動學參數與肢段協調兩種觀點分別檢驗兩組間差異，以提供不同焦點指導動作學理依據。方法: 以40名國小學童均質分成內在與外在注意力焦點兩組，以高速攝影機收取立定跳遠過程運動學參數。結果: 外在焦點組的確較內在焦點組更能增進跳遠成績，從運動學參數來看，外在焦點組在過程中出現相對較小的髖關節角度。肢段協調方面，兩組相同點為膝與踝關節最大角度間達顯著正相關、髖與膝關節最大角速度和角加速度間達顯著正相關，差異點為內在焦點組之肘與髖關節最大角度達顯著正相關，外在焦點組顯示髖與膝關節最大角度達顯著正相關、肩與踝關節角速度和角加速度間達顯著正相關。結論: 從單一運動學參數觀點檢驗兩組動作差異並不明確，從肢段協調觀點得知，外在焦點組顯示更多關節角度、角速度與角加速度的協調性。
Purpose: Motion coordination is one of the important research topics in the field of motion control in recent years. Past studies had pointed out that, for the standing long jump the external focus of attention guidance had different "starting moment" from the internal focus of attention. However, it is not clear whether there is a difference in the coordination patterns of various limbs between the two focus strategies, and whether it is related to better standing long jump performance. This study examined the differences between the two focus strategies from the single kinematic parameter and limb coordination. Methods: Forty elementary school children were equally divided into two groups: internal focus group and external focus group. High-speed cameras were used to capture the each joint during the standing long jump. Results: The external focus group had better standing long jump performance than the internal focus group significantly. For the kinematic parameters, the external focus group showed smaller hip joint angle. In terms of coordination, both groups had significant positive correlation between the maximum angle of the knee and ankle joints, and significant positive correlation between the maximum angular velocity and angular acceleration of the hip and knee joints. In the internal focus group, the maximum angle of the elbow and hip joints was significantly positively correlated. In the external group, the maximum angle of the hip and knee joints were correlated significantly, and the angular velocity and angular acceleration of the shoulder and ankle joints showed significant positive correlation. Conclusion: There was not a significant difference between the two groups from the viewpoint of kinematic parameters. For the coordination (pattern of the limbs), the external focus group was more coordinated in joint angles, angular velocities and angular accelerations, and those are the reasons resulting in better standing long jump performance.