Article of footwear includes a sole, an insole overlying the sole, the insole having in a surface thereof a groove having an inlet and outlet in an edge of the insole, the groove winding substantially throughout the length and width of the insole upper surface. A tube is disposed in the groove and extends throughout the length of the groove and has an inlet portion extending from the groove inlet at the edge of the insole and an outlet portion extending from the groove outlet. An upper fixed to the sole has apertures through which extend the tube inlet and outlet portions.