Abstract: In this paper, the effect of the section size on thestrain energy of vaulting poles is investigated in the staticequilibrium condition. The variation of the wall thickness of the vaultingpole along its length is obtained. The deformation curve of the vaulting poleunder the ultimate state is computed by Finite Element Method, and theassumption that the ultimate deformation curve is in a form of arc is verified aswell. The performance index is modified based on the energy conservation,taking into account the contribution of the vaulter's muscle work to the height of polevaulting. The computational formula of thevaulting height is derived as a function of the weight, the height ofathletes and the pole grasp height.