Motion-Control refer to designs or devices found in athletic shoes that control the inward rolling/pronation of the foot.
Pronation describes a slight inward rolling motion the f oot makes during a normal walking or running stride. During walking or runnin, the foot and ankle rolls slightly inward to accomodate movement. Some people, however, over-pronate and roll more than normal. With over-pronation, the arch of the foot flattens and causes excessive stress and pressure on the soft tissues of the foot. Over-pronation is more common in those with flat feet, and can lead to foot aches and pain, such as Knee Pain.
Wearing the proper footwear, using shoe inserts/insoles, or orthotics can help reduce over-pronation. Motion-Control Devices found in athletic shoes controls the inward rolling/pronation of the foot.