Purpose: The "Joint Resources - Sedentary Behavior Study" (JR-SB) revealed significant behavioral and cardio-metabolic effects of reducing daily sedentary behavior replaced by light-intensity physical activity in patients with rheumatoid arthritis. This study explores the participant perception and experiences of the intervention and impact on the participants' health, family and physical activity behavior.Materials and Methods: A mixed-methods study design, including quantitative and qualitative data, was applied. Quantitative data were collected post-intervention using a questionnaire (n = 69) evaluating experiences of participation in the intervention. By maximum variation sampling, 18 participants were recruited to three focus group interviews with discussions of intervention elements. Data from the two sub-studies were collected and analyzed separately, although integrated at the interpretation and reporting level.Results: Based on four overarching themes, results indicated participant satisfaction with the individually tailored, behavioral approach and the focus on light-intensity physical activity rather than higher intensities. Study participation had an additional positive impact on the behaviors of family and social relations. Conversely, the family motivated the participants to achieve their physical activity goals.Conclusions: The study results support the use of individually tailored and behavioral approaches to reduce sedentary behavior, increase light-intensity physical activity and improve physical abilities in patients with rheumatoid arthritis. IMPLICATIONS FOR REHABILITATIONThis paper presents positive participant perception and motivation for an individually tailored, behavioural intervention that aimed to reduce sedentary behaviour replaced by light-intensity physical activity in patients with rheumatoid arthritis.The results indicate that especially the focus on light-intensity physical activity, a consistent focus on the individual's everyday life and continuous support from health professionals motivated the participants to reduce their daily sedentary behaviour - also in the long term.Involvement of participants' family members seems to have influence on their own physical activity behavior as well as on the participants' motivation for changing physical activity behavior.Together with earlier evidence, the results underpin the use of behavioural strategies to support patients with rheumatoid arthritis in achieving their physical activity goals and in improving the abilities needed to manage their everyday lives.