Effects of physical activity on insulin action and glucose tolerance in obesity

Purpose: The purpose of this paper is to examine the effect of physical act ivity on glucose tolerance in relation to obesity. Methods: We reviewed cur rent literature, with particular emphasis on randomized clinical trials, to prepare an evidence-based evaluation of the effects of physical activity o n glucose intolerance in obesity. Results: This literature review indicates that physical activity has favorable effects on reducing insulin resistanc e in obesity and among patients with type 2 diabetes mellitus. Improvement in glucose tolerance is less consistently observed and is related to intens ity of exercise, collateral changes in adiposity, the interval between exer cise and testing of glucose tolerance, and the baseline severity of glucose intolerance. Conclusion: A review of currently published clinical trial da ta supports the conclusion that physical activity can reduce insulin resist ance and improve glucose intolerance in obesity.