Inclusion Criteria:

• 1. Age: 18-45 years old; equal numbers of men and women
• 2. Body mass index (BMI): 25.0-34.9 kg/m2,
• 3. Sleep Habits: habitual self-reported average total sleep time (TST) \<6.5 hours per night for prior 6 months

Exclusion Criteria:

• 1. Clinically diagnosed sleep disorder or major psychiatric illness
• 2. Evidence of significant organ dysfunction or disease (e.g., diagnosed diabetes, cardiovascular disease, or kidney disease)
• 3. Use of prescription drugs or substances known to influence sleep or glucose metabolism
• 4. Shift-work: current or history of within last year
• 5. Weight change: \>10% of body weight over prior six months
• 6. Experiencing menopause or post-menopausal
• 7. Current enrollment in weight loss or physical activity program like the Diabetes Prevention Program
• 8. Currently pregnant or planning to become pregnant, or currently lactating.
• 9. Currently smoking
• 10. Alcohol intake \>3 drinks per day or \>14 drinks per week