Feasibility of Choose to Move Replacement Ready

Choose to Move (CTM) an effective 3-month, choice-based health-promoting program for low active older adults being scaled-up in phases across British Columbia (BC), Canada. Choose to Move Replacement Ready (CTM-RR) is an adapted version of the program tailored to support individuals with hip and/or knee osteoarthritis on surgical waitlists for TKR/THR, with the overall goal of enhancing key health outcomes. Trained activity coaches hired by the Active Aging Society will deliver CTM-RR to individuals on surgical waitlists for TKR/THR. The investigators will then evaluate implementation of CTM-RR, and the impact of CTM-RR on participants' physical and social health. The primary objective of this trial is to: 1. Assess implementation outcomes (participant recruitment, retention, dose delivered/received, fidelity) of the adapted CTM model against predetermined feasibility targets. The secondary objectives are to: 2. Describe implementation determinants (acceptability, feasibility, appropriateness) and outcomes (reach, adaptations, perceived participant responsiveness, adoption) of the adapted CTM model. 3. Evaluate the preliminary estimates of effectiveness of CTM-RR. Specifically, whether CTM-RR increases participants' pre-operative moderate-to-vigorous physical activity, light physical activity, mobility, psychosocial health, and self-efficacy to manage their condition; improves their perception of their joint condition, function, and quality of life; and decreases pain, social isolation, loneliness, and sedentary time 4. Assess whether participant-level health benefits, if any, are maintained 3 months after participants complete the CTM-RR program. In partnership with the Active Aging Society, the investigators aim to deliver 6 CTM-RR online programs over 9-months to approximately 60 participants total across BC. There is no cost to participate in the CTM-RR program, and individuals may participate in CTM-RR regardless of whether they choose to be evaluated as part of this trial. The investigators will conduct a feasibility trial using a hybrid implementation-effectiveness type 2 trial design. Data will be collected at 0 (baseline), 3 (post-intervention), and 6 (long-term follow-up) months to assess implementation and impact of CTM-RR, and maintenance of any program-related benefits. The investigators will also collect physical activity logs from program participants (weekly, during program participation).