Hypothesis: Insulin-resistant African-American and Hispanic adolescents will show significant improvement of insulin sensitivity (SI) and positive changes associated with fibrinolytic markers and lipid profile after a two month supervised aerobic training.

The specific aims of the study are 1) To determine the effects of exercise on insulin sensitivity in insulin-resistant African-American and Hispanic adolescents; 2) To determine the effects of exercise on fibrinolytic markers in insulin-resistant African-American and Hispanic adolescents.

The hypothesis is that insulin-resistant African-American and Hispanic adolescents will show significant improvement of insulin sensitivity (SI) and positive changes associated with fibrinolytic markers and lipid profile after a 1 month pre-training period and two-months of supervised, moderate intensity aerobic exercise.

Part I. Insulin-resistant African American and Hispanic adolescents from the DC metro area will be recruited through various recruitment efforts. Potential participants will have 2 screening visits in which their medical history, physical activity level, body mass index, and fasting plasma glucose and insulin or OGTT results will determine eligibility.

Part 2. If inclusion criteria is met, the subjects will undergo a 2 week dietary stabilization period, treadmill exercise testing, IVGTT, blood draws for fibrinolytic and lipid markers, DEXA scan, and anthropometric measurements. Subjects will have a 1 month pre-training period and 2 months of supervised, moderate intensity aerobic exercise. All baseline testing will be repeated after the exercise period to see any significant differences.

Inclusion Criteria:

• Must be between 14 to 18 years old
• Being African American or Hispanic
• Sedentary (exercising less than twice a week for less than 20 minutes)
• Non-smoker
• At high risk of developing insulin resistance
• BMI for age grater than or equal to the 95th percentile

Exclusion Criteria:

• History of chronic illnesses
• Thyroid dysfunction
• Taking medications know to affect metabolism
• Being pregnant or lactating

Insulin-Resistant Minority Adolescents