HOROWITZ, J.F. Regulation of lipid mobilization and oxidation during exercise in obesity. Exerc. Sport Sci. Rev. Vol. 29, No. 1, pp 42–46, 2001. Obesity is associated with metabolic disorders that may be related to alterations in lipid mobilization and oxidation. Although exercise is essential for successful weight management, the regulation of fatty acid metabolism during exercise in obesity is unclear. This review discusses factors that regulate fat metabolism during exercise and the effects of endurance training on these responses.