床運動における、前転とび前方伸身宙返りの発展過程に関するバイオメカニクス的分析研究

抄録

There are three basic types of forward handspring, followed by a forward somersaults that are performed on the floor, a forward handspring followed by a tucked forward somersault, a forward handspring followed by a piked forward somersault and a forward handspring followed by a stretched forward somersault. They are different forms of movements in the second position from forward handspring as first position. Each forward handspring, followed by forward somersaults are a composite movement consisting of a forward handspring and a forward somersault. The forward handspring, followed by a tucked forward somersaut develops into a forward handspring, followed by a piked forward somersault, and they develop into a forward handspring, followed by a stretched forward somersault: the basis for these basic movements.
This study attempts to determine the technical points of difference in the three basic types of forward handspring, followed by a forward somersault and to determine an efficient take-off for the forward somersaults develops into a stretched forward somersault. Althought the first part is technically similar there are differences in the take-offs due to the differences in the second part. In the landing from the forward handspring for a forward somersault in the first part when the heels and toes touch the floor the forward somersault is performed by bending the body backwards, leaping from a backward falling posture into th preparation for the leap. From this posture the spring is performed by returning the backward bending upper body toward the position which completes the leap. The motion here resembles the rebound of a bow, with the legs hitting the floor.
This enables the upward leap and subsequent forward rotation for the forward somersalt in second part. In a forward handspring follwed by a stretched forward somersault, the differences are mainly in the utilization of the efficiency of rotation after the take-off from the other two types. And, the differences are in the leap into the forward somersault in the second part and the movement of the upper body to assist the leap by using the legs.