The foot securing device comprises, inside the shell, a single traction element such as a cable. This cable has a first portion which embraces a pressor in the metatarsal region and is inclined with respect to the longitudinal axis of the shell. Conveniently, the firt portion of the cable extends from the inner part of the foot adjacent to the big toe towards the outer part thereof in the direction of the instep. The cable furthermore has a second portion extending rearwardly with respect to the boot, which affects the region of the heel of the foot, and/or with a third portion extending transversely above said presser in the foot instep region. Advantageously, a spool for tensioning the cable is associated therewith.