5. Conclusions
This study demonstrated that a structured, instructor-led group-based exercise and behaviour-change counselling program based on HAPA was beneficial from multiple perspectives for adults with OA. Improved psychological and physical health was described. Changes in attitude towards physical-activity engagement was underpinned by improved self efficacy and mastery, with social support added to the benefits. Thus, health professionals can consider including behaviour-change techniques in their practice, which may enhance the effectiveness of interventions; therefore, promoting physical activity to inactive adults on the hip and knee waitlist for surgery.