The Short Foot Exercise is an exercise that is claimed to correct flat or pronated feet.
Curated Resources:
https://podiatryarena.com/index.php?articles/short-foot-exercise.8/ (Podiatry Arena)
http://foot-info.com/short-foot-exercise/ (Foot Info)
https://podiapaedia.org/wiki/physical-therapies/exercise-therapy/muscle-strength-therapy/foot-strengthening-exercises/short-foot-exercise/ (PodiaPaedia)