Axial spondyloarthritis (axSpa) is a chronic inflammatoric autoimmune disease of the back with a prevalence around 1,4% (1) . In patients decreased function and decreased quality of life as well as chronic pain are strong burdens . Despite modern treatments like biological agents just 25% of the patients are at remission (2) . Besides the pharmacological treatment physical activity is known to be very important to gain disease control. A low physical activity is related to a higher disease activity and a high physical activity to better disease control. Until now there is no structured capture of the daily movements of patients with axial spondylarthritis in clinical practice. Our goal is to analyse the relationship between movement and disease activity and to implement concrete recommendations for movement in patients with axSpa. The primary objective of the study is to investigate which type, frequency and intensity of movement are helpful in gaining and remaining disease control in patients with axSpa. Methods This monocentric longitudinal study recordes movement, sport and physical parameters like heart frequency and heart rate variability through an observational period of 6 month via smartwatch. Meanwhile we record disease activity, pain and functional outcomes with regular surveys every two weeks. Patients in every phase of disease are eligible for inclusion, but they do must have an own iPhone due to software reasons. Data is collected in a specially programmed study-app. Fifty participants will be included in this study. Until now we have 24 patients included since april 2024. Patients come to clinic every 3 month as this is our standard in outclinic patients. We than do anamnesis and a physical examination. After the study period of 6 month we transmit the mobility and disease-related data of the surveys of the patients mobile device to our system. The primary endpoint is to find exact recommendations for concrete movement in patients with axSpa. So this is the first study that wants to give concrete recommendations for movement in patients with axSpa with the help of mobility tracking with smartwatches. This could help to prevent flares and also to recover quicker from a flare. 1. López-Medina und Moltó, Update on the epidemiology, risk factors, and disease outcomes of axial spondyloarthritis. 2. Pina Vegas u. a., Factors associated with remission at 5-year follow-up in recent-onset axial spondyloarthritis: results from the DESIR cohort.