Ive heard shock absorption is the most important function of an insole. Is this true?
A. For many people with normal arches and no stability problems this is mostly true. But there is more to this story. The mid-sole of a shoe should provide the majority of the shock absorption. The main purpose of an insole is to act as an interface between the foot and the inside of the shoe. Insoles are supposed to provide cushioning and to redistribute the pressure of the foot more evenly. Due to the limitation on how thick an insole can be made and still fit into a shoe, replacement insoles might improve the shock absorbency of a new shoe by about 20%. But people who have an unstable or hyper mobile foot (like people with flexible flat feet or low arches) need more motion control as opposed to cushioning. This is why shoe manufacturers make stability & motion control shoes much firmer than their cushioning shoes.
