Sixty adults (age 50+) with knee OA and pain will be recruited. A physician will diagnose the severity of knee OA through radiographs. Participants will be tested in the KBR Human Performance Lab on the campus of Winston Salem State University (WSSU). Participants will complete a demographic form and a survey about their knee pain and function. Participants will be evaluated under two conditions: 1) with SAI placed inside the shoe and 2) shoes alone. There are three walking tasks: 1) walking 25 feet at their usual pace; 2) walking 25 feet at a fast pace; 3) walking six minutes for distance; and a 4) biomechanical gait analysis. After each of the walks, participants will rate the amount of knee pain they experienced. During the biomechanical analysis, participants will walk down a 20 foot walkway while wearing reflective markers. Eight cameras and a force plate embedded in the walkway will measure the amount of body movement and the forces applied to the leg joints during walking.