Supination and pronation are two common terms used to describe the movement of the foot and ankle.
Supination refers to the inward rotation of the foot and ankle. When the foot is in a supinated position, the weight is primarily borne by the outside edge of the foot and the ankle is bent outward. Supination is often used to describe the action of rolling onto the outside edge of the foot when walking or running.
Pronation, on the other hand, refers to the outward rotation of the foot and ankle. When the foot is in a pronated position, the weight is primarily borne by the inside edge of the foot and the ankle is bent inward. Pronation is often used to describe the action of rolling onto the inside edge of the foot when walking or running.
Both supination and pronation are normal and necessary movements of the foot and ankle that help to absorb shock and maintain balance when walking or running. However, excessive pronation or supination can lead to problems such as foot and ankle pain or injuries.