If you feel like you’ve just been kicked in the bottom of your heel, but turn around to see nobody there, you may be experiencing an issue with your Achilles tendon or plantar fascia.

18 19 Heel lifts do not require active engagement to exert their effects—adherence is usually high. Heel lifts reduce ankle joint dorsiflexion during running, and reduce gastrocnemius muscle length ...

Background Orthotic heel lifts are thought to lower tension in the Achilles tendon, but the evidence supporting this is equivocal. Objective To investigate the effect of a 12 mm in-shoe orthotic heel ...