Is there any conclusive evidence that exercise alone reduces glucose intolerance?

Abstract

Physical activity improves insulin sensitivity and glucose metabolism, although such effects are short-lasting and regular exercise is needed to sustain them. Weight loss, especially loss of visceral fat, appears to be especially important in improving metabolic function and clinical outcomes. The most important consequences of exercise are probably promotion of weight loss and prevention of weight gain. Substantial weight losses, associated with significant improvements in glycaemic control and reductions in the incidence of type 2 diabetes, have been observed in intervention studies in overweight or obese subjects. These benefits were achieved using intensive lifestyle interventions, pharmacotherapy or surgery. Thus, programmes of diet and exercise aimed at achieving control of body weight should play a central role in strategies for diabetes prevention.