Abstract: A clothing article for a foot including a sole including a sealed collapsible air cavity having disposed therein a return support for expanding a collapsed air cavity wherein the air cavity includes an outlet permitting a quantity of air to exit when the air cavity is collapsed; an upper, coupled to the sole, for covering a portion of the foot; an air-actuated active element coupled to the upper, the active element including a first mode and a second mode, the active element biased to the first mode and responsive to the quantity of air to transition from the first mode to the second mode; and a communication channel, coupled to the outlet and to the active element, for transferring the quantity of air from the air cavity to the active element.

Abstract: Inner boot, particularly for a sports shoe such as a ski boot, an in-line roller skate or an ice skate, comprising a front portion, that covers the toes and part of the forefoot of the user, and a rear portion, that extends at the region of the plantar's arch up to the heel; the front portion is connected to the rear portion by way of one or more interconnection bellows having, in a rest position, its maximum elongation.