These changes in lifestyle resulted in large changes in diabetes risk: 10.6% of the intervention group developed diabetes over 5 years compared with 28.6% of the control group. Improvements in glucose tolerance were related to both increased fitness and weight reduction; both contributed equally and independently to reduction in risk of diabetes. Based on these results, the DPP Steering Committee chose to include a lifestyle arm in the trial and to focus on modifying both body weight and physical activity.