Mental illness is an important public health priority . There is a wealth of research evidence suggesting that regular physical activity is beneficial for individuals with mental health disorders  yet an additional lifestyle factor that may be important is sedentary behavior. Sedentary behavior can be defined as any waking activity characterised by an energy expenditure ≤ 1.5 metabolic equivalents and a sitting or reclining posture . It is now well established that sedentary behavior is independent of an individual’s physical activity levels in their associations with health . Epidemiological studies have consistently shown that spending excessive time engaged in sedentary behaviors may have a negative impact on several physical health outcomes yet the research examining the relationship between sedentary behavior and mental health outcomes (e.g., depression, anxiety, quality of life) is somewhat sparse with limitations in the assessment and classification of sedentary behavior.