This research is being done to determine whether acute exercise causes differences in numbers of novel blood factors associated with vascular health in college-aged adults across different physical activity habits. As only ~50% of cardiovascular (CV) events can be explained by traditional CV risk factors such as high blood pressure and high cholesterol, it is anticipated that this research will provide a more comprehensive look into novel risk factors that may better explain CV risk and that may be modifiable through regular physical activity.

Inclusion Criteria:

• 18-29 years of age; healthy male and female; Physically inactive, defined as participation in less than 20 min of continuous endurance exercise on fewer than 2 days/week; Recreationally active, defined as participation in 30 min/day of moderate-intensity cardiovascular activity on greater than 4 days/week; Highly active- defined as performing 30-60 min of moderate- to vigorous-intensity endurance exercise greater than 5 days/week.

Exclusion Criteria:

• currently pregnant, previously diagnosed coronary heart disease or congenital heart disease, serum total cholesterol >200 mg/dl, low-density lipoprotein cholesterol >130 mg/dl, high-density lipoprotein cholesterol < 35 mg/dl, fasting glucose >100 mg/dl, systolic blood pressure > 130 mmHg, diastolic blood pressure >90 mmHg, and BMI >30 kg/m2.