My final essay for my Sports Nutrition post-grad was on beetroot and sport performance, which turned out to be such an interesting topic. Everything in this field is relatively new and more and more research is being carried out all the time. Beetroot has long been a remedy for high blood pressure, with the elderly population big fans of beetroot juice. This is to do with beetroot’s vasodilatory properties, opening up the blood vessels and allowing blood to flow through more easily. This knowledge spurred the sports scientists into research on vasodilation and sport performance.
The magical compound within beetroot is the nitrate, which is broken down into nitrites and then nitric oxide in the body – it is nitric oxide that is a powerful vasodilator. Nitric oxide has more recently been found to lower the oxygen cost of exercise, meaning that ATP is produced more efficiently and activity levels can be maintained. Many studies have found that performance is enhanced by this, allowing people to exercise for longer and improving the power output of some exercise tests.
There is speculation over the safety of nitrates as a supplement as nitrite salts are those things used as preservatives in cured meat that when broken down in the body, produce a carcinogenic substance. The wonderful thing about beetroot however (as with many other vegetables), is that the antioxidants contained within them, for example vitamin C, prevent this harmful breakdown process. So the lesson for athletes here is to not consume nitrates and nitrites as a supplement, but to include nitrate-rich vegetables in the diet to reap the benefits of nitric oxide on performance.
A good dose of nitrate can be consumed with 500ml of beetroot juice or through 100-300g of other nitrate-rich vegetables such as spinach, rocket and celery. Recommendations for supplementation are that beetroot juice or similar nitrate be consumed 3 hours before training and competition and a daily dose will allow plasma nitrite levels to remain elevated.
For pre-competition nutrition plans, it is a good idea to include beetroot and other nitrate-rich veg in the week leading up to competition. Beetroot is a great addition to salads, goes nicely with oily fish (try this mackerel, sweet potato and beetroot dish) and can be made into soups and dips (this is a goody). It is also lovely combined with chocolate and I will try and find a healthier chocolate and beetroot brownie recipe soon.