In the US, type 2 diabetes affects 90 percent of the 15.6 million individuals with diabetes (DM) and is associated with a two to fourfold increase in cardiovascular disease (CVD). Although postprandial oxidative stress, CHO and lipid metabolism have been implicated in the pathogenesis of CVD, the ability of acute aerobic exercise to modify these variables has not been explored in type 2 DM. This study will compare the effects of an acute bout of aerobic exercise (45 minutes of treadmill walking at 60 percent V02 Max) in a group of physically untrained subjects with younger-onset type 2 DM and control subjects on: (1) parameters of postprandial CHO and lipid metabolism (glucose, insulin, C-peptides, triglycerides), following 3 meals; (2) parameters of postprandial oxidative stress (total MDA, total hydroperoxides) and LDL susceptibility to oxidation, following 3 meals. In addition, the relationship between baseline insulin sensitivity, antioxidant status, VO2Max and postprandial changes in parameters of oxidative stress CHO and lipid metabolism will be explored. The study will include 11 subjects with type 2 diabetes (age 18-40 years) with duration of diabetes (< 7 years) who will participate in a nonexercise and exercise protocols, performed in random order. On day 1 of the exercise protocol, a euglycemic, hyperinsulinemic glucose clamp will be performed. On day 2 at 0800 hours. baseline parameters of oxidative stress, LDL susceptibility to oxidation, CHO and lipid metabolism will be obtained prior to an acute bout of aerobic exercise and periodically throughout the postexercise period, during which three meals will be consumed. The diet will follow American Heart Association (AHA) National Cholesterol Education Program (NCEP1) guidelines with 30 percent fat as energy, with 10: 10: 10 percent from saturated, monounsaturated and polyunsaturated fat, respectively with 113 of energy requirements to be consumed at each meal. On nonexercise experimental day, the same protocol will be followed without the acute exercise bout. The use of aerobic exercise to influence CHO and lipid represents a new approach to using aerobic exercise as a treatment for type 2 diabetes with a long-term goal of impacting complications, such as CVD.
