Predictors of sedentary behaviour in adults: the role of social media addiction and physical activity – a cross-sectional study from Turkey

Background: Sedentary behaviour is increasingly recognised as a major global public health concern due to its well-established associations with adverse health outcomes. Despite the rapid rise in digital media use, research examining the relationship between digital media use and sedentary behaviour in adult populations remains limited, especially in developing countries such as Turkey, where digital access and usage patterns are rapidly evolving. Therefore, to examine the associations between social media addiction and sedentary behaviour and to identify the predictors of sedentary behaviour in adults. Methods: This cross-sectional analytical study was conducted online with volunteer participants between April and June 2025. A total of 442 individuals aged 18-65 years living in Turkey participated. Data were collected using the sociodemographic form, the Bergen Social Media Addiction Scale, the Sedentary Behavior Scale, and the International Physical Activity Questionnaire-Short Form. Results: = 0.007, P < 0.05) significantly improved the model. Conclusions: Hierarchical regression analyses showed that daily internet use was the strongest predictor of sedentary behaviour, while social media addiction had a small but significant effect. Physical activity was not a significant predictor, and several sociodemographic factors (age, gender, education, income, and employment) were also associated with sedentary behaviour. Overall, sedentary behaviour appears to be influenced by both demographic and behavioural factors, with digital addiction contributing modestly beyond traditional predictors.