Organ transplantation remains the most optimal therapeutic method for treating end-stage solid organ failure. In 2023, around 100 solid organ transplants were performed in the Republic of Croatia, including 48 heart transplants, with the first simultaneous heart and liver transplant at University Hospital Centre Zagreb. Early mobilization is a physiotherapy intervention in the rehabilitation process, initiated immediately after injury, illness, or surgery. The goal of early mobilization is to help patients recover as quickly and fully as possible while preventing or minimizing complications associated with prolonged immobilization. Heart transplant patients have reduced exercise capacity due to cardiovascular and musculoskeletal changes. Impaired vascular function and diastolic dysfunction cause reduced cardiac output, leading to decreased peak oxygen uptake in heart transplant recipients. Early mobilization improves cardiac and vascular endothelial function in heart transplant recipients. All patients post-heart transplant should begin early mobilization with therapeutic exercises of the upper and lower limbs and respiratory physiotherapy to facilitate early verticalization. (1) New findings confirm that early mobilization of patients is inversely related to metabolic syndrome following liver transplantation. (2) Therefore, it is recommended to perform early mobilization interventions to reduce the complications of metabolic syndrome and potential post-transplant immunosuppression disorders in liver transplant recipients. Therapeutic exercises should be performed more frequently throughout the day, gradually increasing the intensity and duration of the exercise sessions to improve aerobic capacity after liver transplantation. Data on long-term follow-up of patients with simultaneous transplants are not available, indicating the need for further high-quality and well-founded studies to demonstrate the long-term benefits of exercise in this population.