Physical activity is an essential first-line treatment for patients with knee osteoarthritis (OA). However, a 2013 systematic review found only 13% met the activity recommendation of 150 minutes or more per week. The primary goal of this randomized controlled trail is to assess the efficacy of a physical activity counseling model, involving a group education session, the use of Fitbit Flex (a wireless physical activity tracking device), and online/telephone coaching by a physiotherapist (PT), to improve physical activity and reduce sedentary time in patients with knee OA. Engaging in regular physical activity can have the additional benefit of improving cognitive functioning.