The metabolic syndrome is highly prevalent in populations around the world, regardless of the definition used. Physical inactivity and obesity are two of the major modifiable risk factors for the metabolic syndrome. Cross-sectional and prospective studies have generally found that levels of physical activity and fitness are inversely related to the prevalence of this syndrome. More recent research has also suggested that sedentary behaviors, such as excessive time spent watching television or using a computer, are significantly associated with an increased risk for this syndrome. Separate but complementary approaches that encourage increased participation in physical activity and discourage sedentary behaviors, both at the individual and population level, may prove useful in reducing the prevalence of this syndrome.