Objective: The association of sedentary behaviour and leisure time physical activity with a validated continuous metabolic syndrome risk score was investigated in adults. Subjects/Methods: A number of 992 adults (559 men) without cardiovascular disease or diabetes. Subjects reported time spent in leisure time physical activity and television watching/computer activities. A validated metabolic syndrome risk score, based on waist circumference, triglycerides, blood pressure, fasting plasma glucose and high-density lipoprotein cholesterol, was used. The metabolic syndrome risk score and time spent in sedentary behaviour and physical activity were analysed as continuous variables using multiple linear regression. Results: Metabolic syndrome risk was positively associated with time spent watching television/computer activities, irrespective of physical activity level, and after adjustment for age, education level, smoking status and dietary intake in women aged >= 45 years (beta=0.184, P < 0.05). Independent of the time being sedentary, moderate to vigorous leisure time physical activity was inversely associated with metabolic syndrome risk in men (< 45 years: beta=-0.183, P < 0.01; >= 45 years: beta=-0.192, P < 0.01) and women aged >= 45 years (beta=-0.203, P < 0.01). Conclusions: Although cross-sectional, the present results support inclusion of efforts to decrease sedentary behaviour in metabolic syndrome prevention strategies for women aged >= 45 years, besides promotion of moderate to vigorous physical activity, since both behavioural changes might show additional effects.