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Background-Exercise capacity is inversely related to mortality risk in healthy individuals and those with cardiovascular diseases. This evidence is based largely on white populations, with little information available for blacks. Methods and Results-We assessed the association between exercise capacity and mortality in black (nϭ6749; age, 58Ϯ11 years) and white (nϭ8911; age, 60Ϯ11 years) male veterans with and without cardiovascular disease who successfully completed a treadmill exercise test at the Veterans Affairs Medical Centers in Washington, DC, and Palo Alto, Calif. Fitness categories were based on peak metabolic equivalents (METs) achieved. Subjects were followed up for all-cause mortality for 7.5Ϯ5.3 years. Among clinical and exercise test variables, exercise capacity was the strongest predictor of risk for mortality. The adjusted risk was reduced by 13% for every 1-MET increase in exercise capacity (hazard ratio, 0.87; 95% confidence interval, 0.86 to 0.88; PϽ0.001). Compared with those who achieved Ͻ5 METs, the mortality risk was Ϸ50% lower for those with an exercise capacity of 7.1 to 10 METs (hazard ratio, 0.51; 95% confidence interval, 0.47 to 0.56; PϽ0.001) and 70% lower for those achieving Ͼ10 METs (hazard ratio, 0.31; 95% confidence interval, 0.26 to 0.36; PϽ0.001). The findings were similar for those with and without cardiovascular disease and for both races. Conclusions-Exercise capacity is a strong predictor of all-cause mortality in blacks and whites. The relationship was inverse and graded, with a similar impact on mortality outcomes for both blacks and whites. (Circulation. 2008;117: 614-622.)

Both observational and interventional studies suggest an important role for physical activity and higher fitness in mitigating the metabolic syndrome. Each component of the metabolic syndrome is, to a certain extent, favorably influenced by interventions that include physical activity. Given that the prevalence of the metabolic syndrome and its individual components (particularly obesity and insulin resistance) has increased significantly in recent decades, guidelines from various professional organizations have called for greater efforts to reduce the incidence of this condition and its components. While physical activity interventions that lead to improved fitness cannot be expected to normalize insulin resistance, lipid disorders, or obesity, the combined effect of increasing activity on these risk markers, an improvement in fitness, or both, has been shown to have a major impact on health outcomes related to the metabolic syndrome. Exercise therapy is a cost-effective intervention to both prevent and mitigate the impact of the metabolic syndrome, but it remains underutilized. In the current article, an overview of the effects of physical activity and higher fitness on the metabolic syndrome is provided, along with a discussion of the mechanisms underlying the benefits of being more fit or more physically active in the prevention and treatment of the metabolic syndrome.