Acute Cardiovascular and Metabolic Effects of Exercise Training in Individuals With Insulin Resistance

Physical Inactivity and Insulin Resistance in Skeletal Muscle

The overall aim of the project is to determine whether or not exercise influences cardiovascular or nervous responses to meal ingestion in individuals with insulin resistance or type 2 diabetes.

Participants will undergo a screening procedure, including telephone screening and physical examination, as well as determination of body composition and fitness. Participants will be asked to complete 5-10 days of supervised exercise training and will undergo testing to assess cardiovascular and metabolic responses to an oral glucose tolerance test, including muscle sympathetic nerve activity, blood flow, and circulating glucose and insulin concentrations at baseline and following training. In addition, day-to-day variations in blood glucose will also be monitored. The overall aim of the project is to determine whether or not acute exercise training influences postprandial metabolic, vascular or autonomic nervous system responses in individuals with insulin resistance or T2D.

Inclusion Criteria:

• Insulin resistant: diagnosed with pre-diabetes or fasting blood glucose >/= 100 mg/dL
• T2D: diagnosed by primary care physician
• BMI: less than 43 kg/m2
• Age: 30-65

Exclusion Criteria:

• Smoking
• Insulin use (other than once daily)
• Underlying conditions that limit ability to exercise safely
• Recent weight gain or loss (>5% of body weight in 3 months)
• Physically active (>30 min aerobic exercise, 2 d/wk)
• Recent (<3 mo) changes in medication use or dose
• Uncontrolled T2D (HbA1c>10%)
• Advanced retinopathy or neuropathy
• Pregnancy