About this Resource
Nitrate (NO3) is a molecule comprised of nitrogen and oxygen and is found in high amounts in green leafy vegetables and beetroot. Beetroot juice is the most common form of nitrate supplement used in clinical research and evidence from systematic reviews and meta-analyses of randomised controlled trials has indicated it can improve endurance exercise capacity and performance.
Grounded in the Research
“NO3 is currently regarded as one of a handful of dietary supplements with a direct, positive effect on athlete’s performance based on the latest consensus statement by the International Olympic Committee (IOC). The effect of NO3 supplementation on performance may be particularly desirable on competition day, where the differences between the competitors are marginal.”
Excerpt from: Macuh, M., & Knap, B. (2021). Effects of nitrate supplementation on exercise performance in humans: A narrative review. Nutrients, 13(9), 3183.
Nitrate is produced in the body as a waste product during oxidation of amino acids. Nitrate (NO3) molecules are then converted into nitrite (NO2), which in turn is converted into nitric oxide (NO). [9] Nitrate supplementation can be used to augment the body’s natural levels of the molecule NO, and it is this which involved in the regulation of blood flow, mitochondrial respiration, muscle contraction and immune function. All of which are important for exercise performance.
Nitrate can be supplemented by consumption of foods high in dietary nitrates. These include leafy green vegetables, some fruits, and even drinking water. By supplementing with nitrate, NO bioavailability within the body can be increased and may lead to improvements in exercise performance. [13]
Beetroot juice has emerged in recent research as a rich source of dietary nitrate, and consumption has been shown to improve a host of factors including endurance exercise performance, exercise economy, submaximal time to exhaustion, cardiorespiratory performance at anaerobic threshold and VO2max. [14]
Why Can Nitrate Help?
Once nitrate is converted to NO, it can have multiple beneficial effects for exercise performance. NO increases the diameter of blood vessels which allows for better oxygen delivery to the working muscles, [10, 15] and may improve perfusion of oxygen into the muscles by increasing the diffusion gradient. [9]
This improved vasodilatory capacity can have beneficial effects for health, such as reduced blood pressure, [16] but also multiple beneficial effects for exercise. Nitrate supplementation has been shown to enhance muscle power, spring, repeated-sprint, and high intensity intermittent exercise performance. [6] This suggests nitrate supplementation can be useful for a wide range of both individual and team sports.
How Should I Use Nitrate Supplementation?
Nitrate consumed is rapidly absorbed through the stomach and small intestine, peaking around an hour after consumption at around 400% of baseline levels. [17, 18] Some nitrate is converted into nitrite by bacteria in the mouth and swallowed, and some is converted into NO in and enters the blood stream, but the majority is absorbed into the blood, where it can be converted to NO as required. Nitrite concentrations take longer to peak in the plasma, at around 2.5 hours after consumption. [19] Interestingly, the use of anti-bacterial mouth wash may blunt this response, by reducing the levels of bacteria in the mouth. [20] With this in mind supplementation should be taken 2-3 hours prior to exercise.
Both chronic (3-15 days) and acute (immediately prior) supplementation of dietary nitrate have been shown to have beneficial effects on exercise economy, capacity and performance. [13]
Nitrate content of individual plants will vary based on factors such as soil, climate and freshness, however the table below contains a guide. In order for supplementation to be effective, it is important that at least 5-6 mmol nitrate is consumed, however it is recommended to use 6-8 mmol/~350-500 mg nitrate as the optimal dose, as this is just as effective as higher doses of 10-12 mmol. [11] The majority of research in this area utilises beetroot juice concentrates which contain ~400 mg nitrate per 70 mL shot, and therefore this is the recommended method of supplementation. [12, 21]
References
[1] McMahon, N. F., Leveritt, M. D., & Pavey, T. G. (2017). The effect of dietary nitrate supplementation on endurance exercise performance in healthy adults: a systematic review and meta-analysis. Sports Medicine, 47, 735-756. https://doi.org/10.1007/s40279-016-0617-7
[2] Maughan, R. J., Burke, L. M., Dvorak, J., Larson-Meyer, D. E., Peeling, P., Phillips, S. M., … & Engebretsen, L. (2018). IOC consensus statement: dietary supplements and the high-performance athlete. International Journal of Sport Nutrition and Exercise Metabolism, 28(2), 104-125. https://doi.org/10.1136/bjsports-2018-099027
[3] Senefeld, J. W., Wiggins, C. C., Regimbal, R. J., Dominelli, P. B., Baker, S. E., & Joyner, M. J. (2020). Ergogenic effect of nitrate supplementation: A systematic review and meta-analysis. Medicine and Science in Sports and Exercise, 52(10), 2250. https://doi.org/10.1249/mss.0000000000002363
[4] Van De Walle, G. P., & Vukovich, M. D. (2018). The effect of nitrate supplementation on exercise tolerance and performance: a systematic review and meta-analysis. The Journal of Strength & Conditioning Research, 32(6), 1796-1808. https://doi.org/10.1519/jsc.0000000000002046
[5] San Juan, A. F., Dominguez, R., Lago-Rodríguez, Á., Montoya, J. J., Tan, R., & Bailey, S. J. (2020). Effects of dietary nitrate supplementation on weightlifting exercise performance in healthy adults: A systematic review. Nutrients, 12(8), 2227. https://doi.org/10.3390/nu12082227
[6] Thompson, C., Vanhatalo, A., Jell, H., Fulford, J., Carter, J., Nyman, L., … & Jones, A. M. (2016). Dietary nitrate supplementation improves sprint and high-intensity intermittent running performance. Nitric Oxide, 61, 55-61. https://doi.org/10.1016/j.niox.2016.10.006
[7] Macuh, M., & Knap, B. (2021). Effects of nitrate supplementation on exercise performance in humans: A narrative review. Nutrients, 13(9), 3183. https://doi.org/10.3390/nu13093183
[8] Campos, H. O., Drummond, L. R., Rodrigues, Q. T., Machado, F. S., Pires, W., Wanner, S. P., & Coimbra, C. C. (2018). Nitrate supplementation improves physical performance specifically in non-athletes during prolonged open-ended tests: a systematic review and meta-analysis. British Journal of Nutrition, 119(6), 636-657. https://doi.org/10.1017/s0007114518000132
[9] Richards, J. C., Racine, M. L., Hearon Jr, C. M., Kunkel, M., Luckasen, G. J., Larson, D. G., … & Dinenno, F. A. (2018). Acute ingestion of dietary nitrate increases muscle blood flow via local vasodilation during handgrip exercise in young adults. Physiological Reports, 6(2), e13572. https://doi.org/10.14814/phy2.13572
[10] Ahmad, A., Dempsey, S. K., Daneva, Z., Azam, M., Li, N., Li, P. L., & Ritter, J. K. (2018). Role of nitric oxide in the cardiovascular and renal systems. International Journal of Molecular Sciences, 19(9), 2605. https://doi.org/10.3390/ijms19092605
[11] Wylie, L. J., Kelly, J., Bailey, S. J., Blackwell, J. R., Skiba, P. F., Winyard, P. G., … & Jones, A. M. (2013). Beetroot juice and exercise: pharmacodynamic and dose-response relationships. Journal of Applied Physiology, 115(3), 325-336. https://doi.org/10.1152/japplphysiol.00372.2013
[12] Gallardo, E. J., & Coggan, A. R. (2019). What is in your beet juice? Nitrate and nitrite content of beet juice products marketed to athletes. International Journal of Sport Nutrition and Exercise Metabolism, 29(4), 345-349. https://doi.org/10.1123/ijsnem.2018-0223
[13] Jones, A. M., Thompson, C., Wylie, L. J., & Vanhatalo, A. (2018). Dietary nitrate and physical performance. Annual Review of Nutrition, 38(1), 303-328. https://doi.org/10.1146/annurev-nutr-082117-051622
[14] Domínguez, R., Cuenca, E., Maté-Muñoz, J. L., García-Fernández, P., Serra-Paya, N., Estevan, M. C. L., … & Garnacho-Castaño, M. V. (2017). Effects of beetroot juice supplementation on cardiorespiratory endurance in athletes. A systematic review. Nutrients, 9(1), 43. https://doi.org/10.3390/nu9010043
[15] Chen, K., Pittman, R. N., & Popel, A. S. (2008). Nitric oxide in the vasculature: where does it come from and where does it go? A quantitative perspective. Antioxidants & Redox Signaling, 10(7), 1185-1198. https://doi.org/10.1089/ars.2007.1959
[16] Bahadoran, Z., Mirmiran, P., Kabir, A., Azizi, F., & Ghasemi, A. (2017). The nitrate-independent blood pressure–lowering effect of beetroot juice: A systematic review and meta-analysis. Advances in Nutrition, 8(6), 830-838. https://doi.org/10.3945/an.117.016717
[17] Jonvik, K. L., Nyakayiru, J., Pinckaers, P. J., Senden, J. M., van Loon, L. J., & Verdijk, L. B. (2016). Nitrate-rich vegetables increase plasma nitrate and nitrite concentrations and lower blood pressure in healthy adults. The Journal of Nutrition, 146(5), 986-993. https://doi.org/10.3945/jn.116.229807
[18] Wylie, L. J., Mohr, M., Krustrup, P., Jackman, S. R., Ermιdis, G., Kelly, J., … & Jones, A. M. (2013). Dietary nitrate supplementation improves team sport-specific intense intermittent exercise performance. European journal of applied physiology, 113, 1673-1684. https://doi.org/10.1007/s00421-013-2589-8
[19] Lansley, K. E., Winyard, P. G., Bailey, S. J., Vanhatalo, A., Wilkerson, D. P., Blackwell, J. R., … & Jones, A. M. (2011). Acute dietary nitrate supplementation improves cycling time trial performance. Med Sci Sports Exerc, 43(6), 1125-1131. https://doi.org/10.1249/mss.0b013e31821597b4
[20] Blot, S. (2021). Antiseptic mouthwash, the nitrate–nitrite–nitric oxide pathway, and hospital mortality: a hypothesis generating review. Intensive Care Medicine, 47(1), 28-38. https://doi.org/10.1007/s00134-020-06276-z
[21] McDonagh, S. T., Wylie, L. J., Webster, J. M., Vanhatalo, A., & Jones, A. M. (2018). Influence of dietary nitrate food forms on nitrate metabolism and blood pressure in healthy normotensive adults. Nitric Oxide, 72, 66-74. https://doi.org/10.1016/j.niox.2017.12.001