Review Article Exercise in the Metabolic Syndrome
Saeid Golbidi,1 Azam Mesdaghinia,2 and Ismail Laher1
of Anesthesiology, Pharmacology and Therapeutics, Faculty of Medicine, The University of British Columbia, Vancouver, BC, Canada V6T 1Z32 Physiology Research Center, Kashan University of Medical Sciences and Health Services, Kashan 87155/111, Iran Correspondence should be addressed to Ismail Laher, firstname.lastname@example.org Received 27 March 2012; Accepted 13 May 2012 Academic Editor: Steve R. McAnulty Copyright © 2012 Saeid Golbidi et al. This is an open access article distributed under the Creative Commons Attribution License,which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The metabolic syndrome is a clustering of obesity, diabetes, hyperlipidemia, and hypertension that is occurring in increasing frequency across the global population. Although there is some controversy about its diagnostic criteria, oxidative stress, which is deﬁned asimbalance between the production and inactivation of reactive oxygen species, has a major pathophysiological role in all the components of this disease. Oxidative stress and consequent inﬂammation induce insulin resistance, which likely links the various components of this disease. We brieﬂy review the role of oxidative stress as a major component of the metabolic syndrome and then discuss the impact ofexercise on these pathophysiological pathways. Included in this paper is the eﬀect of exercise in reducing fat-induced inﬂammation, blood pressure, and improving muscular metabolism.
The metabolic syndrome (MS) describes a constellation of hypertension, diabetes, and dyslipidemia that is caused by abdominal obesity [1, 2] and has also been variously termed X syndrome, insulinresistance syndrome, and the deadly quartet . The diagnostic criteria for MS have been set out by diﬀerent organizations with slight variations in these criteria as shown in Table 1. The global increase in prevalence of the MS that is rampant in both industrialized and developing countries is associated with an increase in obesity. For example, in a study of 12363 US men and women using theNational Cholesterol Education Program’s Adult Treatment Panel III guidelines, the MS was diagnosed in 22.8% and 22.6% of the men and women, respectively . This syndrome was present in 4.6%, 22.4%, and 59% of normal weight, overweight, and obese men, respectively, and a similar distribution was observed in women. Higher body mass index (BMI), current smoking, low household income, high carbohydrateintake, and physical inactivity were associated with increased odds. The MS can be present in diﬀerent forms, according to the combination of the diﬀerent components of the syndrome, and it is well established that it increases the risk for the development of cardiovascular disease, type II
diabetes, and cancer [5–7]. It is not yet known how the MS is triggered or how the diﬀerent componentsare causally linked, but insulin resistance is strongly suspected as a common pathophysiologic link [8, 9], since it is clear that there is a positive correlation between body weight and insulin resistance and the risk of developing all the metabolic abnormalities associated with insulin resistance . However, recent data suggests that MS and obesity do not always occur in concordance as there issome evidence for conditions of benign obesity [10–14]. For example, some studies suggest that frank obesity does not necessarily translate into insulin resistance and increased risk for metabolic comorbidities. In a cross sectional study of 5440 participants of the National Health and Nutrition Examination Surveys 1999–2004, 31.7% of obese adults (BMI ≥ 30) were metabolically healthy . In...