US Patent 9700077 Article of apparel with variable air permeability

An article of apparel may include a torso region with a front area, a back area, and a pair of side areas. At least a portion of each of the side areas are formed from a material with (a) a first air permeability when unexposed to water and (b) a second air permeability when exposed to water. The first air permeability may be less than 279 cm3/second per cm2 measured in accordance with ASTM D 737, and the second air permeability may be greater than 279 cm3/second per cm2 measured in accordance with ASTM D 737. In some configurations, at least a portion of the back area may be formed from the material. The article of apparel may be a shirt, and the article of apparel may include arm regions that extend outward from the torso region.