摘要：Forward upward circling is an exercise in which the body rotates around a horizontal bar using forward upward movement of the legs. This study aimed to clarify the technical tasks in forward upward circling performed by elementary school childrenaccording to skill level by constructing motion models of the exercise. Motions and body composition indices of 52 fifth-grade elementary school childrenwere collected. Motions were recorded in two dimensions inthe sagittal plane by using a high-speed camera. All participants were classified into excellent,good,poor,or unsuccessful groups based on subjective evaluation. There were no significant differences in body composition indices among the four groups,suggesting that technical characteristics have a greater effect on the success of forward upward circling compared with physical characteristics. In the excellent group,the maximum angular velocity of the swing leg was large and vigorous forward upward circling was performed in a short time. In the good group,the maximum angular velocity of the support leg appeared earlier but the trunk was not raised in a short time from the inverted suspended position. In the poor group,the trunk leaned backward during the non-support phase and the hip joint did not rotate close to the horizontal bar in coordination with the swinging motion of the swing leg. In the unsuccessful group,the trunk leaned backward and the elbow joint extended during the support phase and the head was not pulled away from the horizontal bar to provide the necessary momentum to rotate the body and raise the support leg.
关键词：physical education;motion analysis horizontal bar;gymnastics;motion model
