Nitrate Supplementation and Muscle Blood Flow

Nitric Oxide Bioavailability and Dynamics of Blood Flow and Vasodilation With Age

The main purpose of this study is to evaluate the effects of an acute dose of dietary nitrate in the form of beetroot juice on skeletal muscle blood flow in response to dynamic knee extension exercise in healthy older adults. All subjects will receive active (rich in dietary nitrate) or placebo (devoid of nitrate) supplementation.

Dietary nitrate (beetroot juice) is reduced to nitrite and nitric oxide within the digestive system of humans. Nitric oxide exerts potent vasodilator effects, which have been shown to reduce blood pressure and enhance exercise economy in humans. This pressure reducing effect may have implications within the regulation of blood flow during dynamic exercise in older adults.

Inclusion Criteria:

• Healthy older adults 60-80 years of age

Exclusion Criteria:

• Hypertension,
• Smoking,
• Heart disease,
• Diabetes,
• Body mass index (BMI) ≥ 30 kg/m2,
• Autonomic disorders and other conditions that may alter blood pressure or vascular function
• Medications that might normally alter blood pressure or vascular function.
• Older women taking hormone replacement therapy medications.