Diabetes has become a nationwide epidemic affecting 18.2 million Americans, and the incidence is expected to increase 122% by the year 2025. The dyslipidemia associated with type 2 diabetes—low HDL-C; high TG; and small, dense LDL-C—contributes to the 2 to 4 times greater risk of individuals with diabetes to have a major cardiovascular event. Niacin, a B vitamin, and aerobic exercise have been shown separately to favorably alter the lipid profile. The present study examined a combination therapy of Niaspan®, an extended-release formulation of niacin, and 16 weeks of aerobic exercise in 23 individuals with type 2 diabetes. The dosage of Niaspan® began at 500 mg/day and increased 500 mg/day every 4 weeks up to a maximum dose of 2000 mg/day. Subjects were advised to gradually progress their frequency, intensity, and duration of aerobic exercise until they were expending at least 1500 kilocalories by week 8. Subjects were instructed to make no changes to their diet or diabetes medication regimen. Lipoproteins and subfractions and selected measures of physical fitness were examined before and after the 16 week intervention. Following the 16 week intervention period, there were significant changes (p<0.05) in HDL-C (+28%), TG (-19%), VLDL-C (-12%), and LDL-C (-9%). There were also significant changes in the larger, more buoyant subfractions HDL2 (+48%), VLDL2 (-15%) and LDL1 (-48%). Other subfractions that are smaller and more dense also changed favorably: HDL3 (+24%) and LDL4 (-15%). Although there was no significant weight loss in this population as a result of the intervention, there were significant changes in submaximal heart rate (124.9±17.6 vs. 116.7±16.3 bpm) and resting systolic (136.8±17.5 vs. 128.3±13.8 mmHg) and diastolic (80.3±12.5 vs. 73.2±9.8 mmHg) blood pressure, adaptations that occur with improvement in physical fitness. There were no changes in fasting plasma glucose or glycosylated hemoglobin, contradicting any deterioration in glucose control. Therefore, the combination of Niaspan® and aerobic exercise is effective at altering the lipid profile in individuals with type 2 diabetes. In addition, this intervention is safe in that it does not adversely affect glucose control. / School of Physical Education, Sport, and Exercise Science