Physical activity (PA) has been identified as an essential tool for the prevention and management of multi-morbidity in patients. Coordination of patients' care through interventions like physical activity referral schemes (PARS) could foster the utilization of PA. This study explored the views of General Practitioners (GPs) and Exercise Physiologists (EPs) as key stakeholders, for optimizing patient care and efficiency of PARS. Sequential explanatory mixed methods design was used to explore the perceptions of these health professionals on PA and coordination strategies for PARS patient care. Data analyses included descriptive and inferential statistics for questionnaires and theoretical framework analysis for the semi-structured interviews. Participants demonstrated a good knowledge of PA and valued PARS. However, the findings unravelled external factors, inter-organisational mechanisms, and relational coordination obstacles that hinder efficient coordination of PARS patient care and delay/limit beneficial health outcomes for patients. Incentivising the PARS initiative and empowering patients to seek referral into the programme, are strategies that could boost PARS efficiency. Improving inter-professional relationships between GPs and EPs could lead to enhanced PARS functionality and efficient coordination of care for patients with chronic diseases.