Overpronation is opposite it to pronation. The pronation is the flattening of feet arch when it lands on the land. The flattering surface gives balance and little shock absorption too. When the foot flattens less, your ankle tilts inward toward the midline of the body, and lower leg muscles help the ankle from rolling inward too far. People having flatter feet has more flexible arches, and that are more likely to flatten very much. That is called overpronation. This kind of foot offers plenty of its own cushioning but doesn’t retain enough of its formation. So your leg and knee try to pick the job to give support. But this is not the job for these parts to do. So, because of their overwork or stress, they send signals of pain and fatigue. However, people with high arches frequently have inflexible feet. That limited cause motion when the foot undergoes once lands. These feet don’t get that typical shock absorption in the leg and the ground shift again more up in the leg finding someplace to be absorbed. And that place is mostly in the knees, shins, or anywhere else. Anyway, not all flatter feet overpronate, even the high arches may experience this too. Over inward ankle rolling because of instability in the muscles of the lower leg.