Beetroot juice as a supplement has become a big trend in the sports nutrition world. With a huge amount of research taking place in the area of dietary nitrate (found in beetroot) and some strong evidence of its benefits coming from it, it is not surprising. So, let’s take a little look into what it is and how it works.
What does dietary nitrate do?
Dietary nitrate is an ion found in food. Once you have consumed nitrate it is converted in the body to nitrite and stored and circulated in the blood. In conditions of low oxygen availability, nitrite can be converted into nitric oxide, which is known to play a number of important roles in vascular and metabolic control. Dietary nitrate supplementation increases plasma nitrite concentration and can help reduce resting blood pressure.
In some individuals nitrate supplementation reduces the oxygen cost of submaximal exercise, which can enhance exercise tolerance (preventing fatigue) and performance hence the interest in the sports nutrition world!
It is important to point out at this stage that there is a lot of individual variability with dietary nitrate. Not everyone will benefit from consuming nitrate rich foods/drinks due to each individual having a different abilities when converting nitrate to nitrite. Therefore, whether or not the nitrite then impacts exercise economy of oxygen cost for exercise and performance varies too. If nitrate does reduce oxygen cost of submaximal exercise then it can also benefit performance, however, both need to happen in that order to have a positive impact.
Why beetroot juice?
Beetroot along with other vegetables such as spinach, and lettuce are rich in dietary nitrate. The food first approach should always be taken and recommended to you by sports nutritionists/dietitians however, whole food nitrate concentrations can vary for example, nitrate can be affected by the growing conditions of the vegetables or the cooking method.
Beetroot is commonly used in sports nutrition due to it being easier to buy in a liquid form and the ability to control the concentration of nitrate. However, consuming nitrate in other forms should have a similar affect, you may just have to eat a full bag of spinach to get the ideal 300-600mg of nitrate rather than simple drinking a couple of beetroot juice shots.
Is timing and dosage important?
Both the timing and dosage like many nutrients in sports nutrition is key. The largest performance advantage dosage is said to be 300-600mg which is approximately 1-2 shots of beetroot juice. Studies have shown that in some endurance athletes the plasma nitrite should be elevated at its peak within 2-3 hours, therefore, having nitrate rich foods or your beetroot shots is optimal as a pre nutrition meal/snack.
Nitrate advantages in sports performance:
As mentioned above, the impact nitrate can have varies greatly amongst individuals. Nevertheless, those that have seen benefits from consuming beetroot juice have increased their nitric oxide levels which helps to dilate blood vessels and improve the blood flow resulting in increased oxygen delivery to muscles, which has then improved the muscles efficiency when using oxygen. Some studies have found it can also aid glucose uptake in the muscles, which could see some great benefits for carbohydrate utilisation in endurance athletes however, more research needs to be done.
Although there is some great research out there, not all studies have shown benefits with some studies showing that the nitrate makes little to no difference to performance.
My advice would be if you are intrigued by this trend and enjoy beetroot juice then try the ideal dosage 2-3 hours before your endurance activity or if you prefer the food first approach load your pre exercise meal with spinach and beetroot. Then worse case, if the nitrate doesn’t have benefits on your performance there are still great health benefits coming from the other nutrients you have consumed from the vegetables.
Top Tip: avoid using antibacterial mouthwash when you are consuming beetroot juice, as this can affect the conversion of nitrate to nitric oxide.
Dietary Nitrate Supplementation and Exercise Performance – Andrew Jones: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4008816/
Sports Dietitians Online: https://www.sportsdietitians.com.au/factsheets/supplements/beetroot-juice-nitrate/