| 摘要 |
There is provided a practice box for pole vaulters, which defines a wedge-shaped recess converging in the forward direction, open upwardly and open rearwardly. The practice box has side edges defining the convergence, which side edges are provided with means for retaining the inertial weight in such a way as to oppose a forward thrust in the practice box. In use the inertia of the practice box allows the vaulter at least to lift-off the ground, but the forward thrust exerted by the pole allows the vaulter to return to the ground without completing the jump. The purpose is to permit practice of the lift-off without requiring a full jump.
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