Beetroot juice is the latest ergogenic phenomenon being used by athletes, writes Hannah Sheridan
The reason beetroot juice is so popular is due to its high concentration of the magic ingredient nitrate. High concentrations of nitrate can be found in a variety of other vegetables, including spinach and lettuce, but the content varies depending on where and when these vegetables are grown. Beetroot remains the most reliable and convenient source of nitrate for use in sport.
Benefits of consuming beetroot juice
» Reductions in the oxygen cost of exercise lasting 5-30min
The efficiency of energy metabolism within the muscle is improved, which means that you require less oxygen to run at the same given speed and the energy cost of muscle power production is reduced
» Enhanced exercise tolerance and capacity
Sparing of certain energy stores and blunted production of fatigue-provoking metabolites improves exercise tolerance, while lowering the energy cost of exercise allows us to exercise for longer
» Reduced blood pressure
Vasodilation of blood vessels reduces blood pressure, demonstrating the wider health benefits of beetroot juice
» Improved cognitive function
Beetroot juice has recently shown to attenuate the decline in decision-making and reaction time that can occur during prolonged exercise events when athletes become increasingly fatigued
» Improved muscle recovery
Beetroot supplementation has recently shown to speed up recovery following eccentric resistance exercise sessions. This finding suggests that beetroot juice may also be useful following weights or plyometric training sessions in addition to running-based sessions. The impact of beetroot supplementation on recovery is a newly investigated topic, which requires further research to fully support the findings.
How does it work?
The underlying mechanisms stimulating improvements in performance occur once dietary nitrates have been converted into nitric oxide within the body. Nitric oxide has the ability to influence muscle function by regulating blood flow, contractility, glucose and calcium homeostasis and mitochondrial respiration and production.
Possible mechanisms include: increased vasodilation of blood vessels resulting in increased blood flow to active muscles; a reduction in the percentage of VO2 max required to complete a given exercise task; the sparing of various energy sources used during high intensity exercise; a reduction in accumulation of metabolites contributing to fatigue.
How much and how often?
A question often asked is ,“how much and how often do I need to consume beetroot juice for it to have performance enhancing effects?” Prolonged (up to 15 days) and acute supplementation with 5-8mmol of nitrate have shown to be effective for improving performance. If you are planning to consume beetroot juice on the day of training or competition, then you will need to consume it two to three hours beforehand allowing time for the nitric oxide levels to peak within the bloodstream.
Beetroot expert, Prof Andy Jones at the University of Exeter, was one of the first researchers to investigate the performance enhancing effects of beetroot juice. His latest review is a great read for those looking to delve further into the research behind the magic bullet, dietary nitrate: Jones, A. M. (2014). Dietary nitrate supplementation and exercise performance. Sports Medicine, 44(1), 35-45.
Nitrate sources Nitrate concentration
Beetroot shots 4-5mmol/shot
100g baked beetroot 4mmol
0.5l beetroot juice 5-6mmol
» Hannah Sheridan BSc, PGDip, MSc, is the lead sports nutritionist at the University of Birmingham Hi-Performance Centre, where she supports national and international level athletes competing across a range of sports