PURPOSE: To improve the characteristic going along a motor function of a foot by providing a tip part allowed to branch and extended from a trunk part stretching from the heel part to the toe direction, forming the whole plane shape in a roughly Y shape or in a roughly H shape, and making the plantar arch part high like an arch.

CONSTITUTION: A trunk part 1c which can be integrated into the inner bottom of a shoe, is constituted of an elastic plate material as a whole, and extends from the heel part 1a to the toe direction and a tip part 1g allowed to branch and extended to a first inner foot bone tip vicinity 1e and a fifth inner foot bone tip vicinity 1f by setting the vicinity of the plantar arch part 1d as a branch point from the trunk part are provided, the whole plane shape is formed in a roughly Y shape or in a roughly H shape, and the plantar arch art 1d is made high like an arch so as to go along a foot sole shape, by which a load of sports is dispersed, a movement function of a foot is facilitated, and fatigue can be reduced.