David Poole, professor of exercise kinesiology and anatomy and physiology at Kansas State University has shown in previous research that the nitrate found in beetroot concentrate increases blood flow to skeletal muscles during exercise.
In a new study published in the Journal of Nitric Oxide, Biology and Chemistry, Poole and colleagues provide the basis for how beetroot juice may benefit football players by preferentially increasing blood flow to fast-twitch muscle fibres - the ones used for explosive running.
In addition to improving athletic performance, the research also found that beetroot juice can improve the quality of life for heart failure patients.
The benefits of beetroot come from the nitrate found within it. The amount of nitrate in one 70-millilitre bottle of beetroot juice is about the same amount found in 100 g of spinach.
"When consumed, nitrate is reduced in the mouth by bacteria into nitrite," said Scott Ferguson, doctoral student in anatomy and physiology.
"The nitrite is swallowed again and then reduced to nitric oxide, which is a potent vasodilator. The nitric oxide dilates the blood vessels, similar to turning on a water faucet, and allows blood to go where it needs to go," said Ferguson.
The beetroot juice consumption resulted in a 38 per cent higher blood flow to the skeletal muscles during exercise and was preferential to the less-oxygenated, fast-twitch muscles.
"Heart failure is a disease where oxygen delivery to particular tissues, especially working skeletal muscles, is impaired, decreasing the capacity to move the arms or legs and be physically active," Poole said.
"The best therapy for these patients is getting up and moving around. However, that is often difficult. Increasing the oxygen delivery to these muscles through beetroot can provide a therapeutic avenue to improve the quality of life for these patients," Poole added.