A flat foot should be called a foot with “completely-fallen-tarsal joint” or “completely-fallen-arch,” as it happens when the tarsal joint falls completely to the ground. People with flexible muscles are prone to have flat feet, even if they are born with high arches. Many people have been told they are born with flat feet. But no one is ever born with flat feet—unless it’s a birth defect. You can see arches in every babies’ feet. They just fall to the ground when they stand on the flat surfaces.
Treatment: Use the orthotics that align the ankle bones. Exercise the plantar muscles by moving toes up and down without moving ankles. Binding the arch areas with elastic tubes can bring the over-stretched foot ligaments back to the right places.