Energy loss in the pole vault take-off and the advantage of the flexible pole

A model of pole vaulting with a flexible pole was developed with the aim of predicting the optimum take-off technique and pole characteristics for a typical world-class pole vaulter. The key features of the model are that it includes the interdependence of the take-off angle and the take-off velocity, and that it accounts for the energy losses in the pole plant and take-off phases of the vault. A computer simulation program was used to systematically investigate the effect of different combinations of take-off velocity, takeoff angle, grip height and pole stiffness on the performance of a world-class male vaulter. For the highest vault with this model, the vault height and the optimum combination of take-off velocity, take-off angle, grip height and pole stiffness were in good agreement with measured values for world-class vaulters using fibreglass poles. The results from the model were compared with those from a model of vaulting with a rigid pole. There was a clear performance advantage to vaulting with a flexible pole. The flexible pole produced a 90 cm higher vault by allowing a 60 cm higher grip and by giving a 30 cm greater push height. There are two main advantages of a flexible fibreglass pole over a rigid pole made of steel or bamboo. A flexible pole reduces the energy dissipated in the vaulter’s body during the pole plant, and it also lowers the optimum take-off angle so that the athlete loses less kinetic energy when jumping up at take-off.