Abdominal obesity, insulin resistance, and the metabolic syndrome: contribution of physical activity/exercise

The metabolic syndrome, a constellation of metabolic abnormalities, which include abdominal obesity, insulin resistance, an atherogenic dyslipidemia, elevated blood pressure, a prothrombotic profile, and inflammation is associated with an increased risk of type 2 diabetes (1), cardiovascular disease (2), and mortality (3). The prevalence of individuals with these clustering abnormalities has been steadily increasing over the past two decades, is now estimated to affect at least a quarter of the US population, and is particularly prevalent among older adults (4). Similarly, abdominal obesity, as crudely estimated by an elevated waist circumference, is the most prevalent manifestation of the metabolic syndrome and affects 36% of men and 52% of women, according to the 1999-2000 US National Health and Nutrition Examination Study (5).