Endurance athletes have been supplementing with beetroot juice for years under the understanding that it can enhance endurance performance by dilating the blood vessels allowing for better oxygen flow to the muscles. Recent research suggests that the benefits of ‘supplementing’ with the dietary nitrate, beetroot juice, may also have benefits for heart disease patients.
Heart disease can overstimulate the sympathetic nervous system. This causes increased heart rate, elevated blood pressure and vaso-constriction of the blood vessels due to elevated sympathetic nerve activation. With this in mind the researchers aimed to administer beetroot juice as a means of supplementation to decrease sympathetic neuron outflow.
The study had a subject group of 20 young adults. Subjects were split into two groups: one group would consume beetroot juice and the other a placebo; both groups unaware of the supplement they were consuming.
Subjects had muscle sympathetic nerve activity (MSNA) measured, along with heart rate, blood pressure and grip test – before and after supplementation.
MSNA was measured by analyzing the ‘burst rate’ variable, which measures frequency of nerve activity. This was reduced for the subjects within the beetroot juice group, compared with the placebo group who saw no such improvement.
This – surprisingly – did not translate into a reduction in blood pressure. However these result do suggest that beetroot juice may be an effective way to reduce sympathetic neuron outflow, although more research is now necessary to examine how this translates through to reducing aforementioned physiological symptoms associated with a stimulated sympathetic nervous system.