They can be made of leather or plastic: as they are not in contact with the feet, they do not affect the breathability features of the shoe. What is important, however, is that they are lightweight and flexible in the right points to make walking easier and avoid tiring the muscles.


The inner lining of the shoe (lining and insole) plays an important role when choosing footwear because it is in contact with the foot and it must ensure proper levels of breathability. Natural materials such as calfskin or goatskin (highly breathable top quality materials) or antibacterial fabrics are therefore recommended.