How much room you have in your shoes, whether or not you can or want to remove your existing shoe insoles, and the type of cushioning and support you need are all important factors when deciding whether a ¾-length insole will work for you. If the instep of your shoes is already tight, adding a ¾-length insole may not work, for example. ¾-length insoles help provide cushion and support without adding volume under the forefoot and toes.