US Patent 7757412 Footwear with improved heel support

An article of footwear including a sole and an upper, the upper including a seat adapted to nest the user's heel, the seat including a first stiffener, and an arrangement for varying the size or volume of the seat provided by the first stiffener, between an expanded position, for which the volume of the seat is relatively large, and a retracted position, for which the volume of the seat is reduced.