REVIEW OF RESEARCH ON BEETROOT JUICE USE PROTOCOLS TO INCREASE ATHLETIC PERFORMANCE

Background. In the past 20 years, nitric oxide has become a milestone in terms of both athlete physiology and
medicine, pharmacology studies. Furthermore, the consumption of beetroot juice, which is rich in nitrates that are
converted into nitric oxide in human body, also has an impact on oxygen delivery to skeletal muscles, muscle efficiency,
increases oxygen and nutrient delivery to various organs and may thus have a positive impact on sports performances
(Bailey et al., 2010). Various protocols are reviewed and the purpose of this review is to find the best protocol that athletes
can use safely and practically.
Research methods. The literature sources used in this paper were obtained from PubMed, MEDLINE,
SportDiscus data, ProQuest, ScienceDirect, Web of science, Scopus and Cochrane central using keywords: beetroot juice,
nitrate, nitric oxide, endurance, protocols. The research analysis provides a summarizing overview regarding the evidence
of beetroot juice used as a dietary supplementation and its effects on training physiology and athletic performance.
Results and discussion. Although most of the studies showed no significant differences in the performance of the
endurance-trained athletes after nitrate supplementation, some studies indicated that with the same maximum and mean
power, the VO2 values decrease after nitrate supplementation (Dominguez et al., 2017). Furthermore, the time to
exhaustion was delayed with nitrate supplementation in a race time trial between 5 and 30 min (Campos et al., 2018). The
results suggest enhanced performance (Jones, 2014). The dose necessary for a significant effect remains unclear since
some results used acute doses of 12 mmol of nitrate and others applied smaller doses (up to 6 mmol/day of nitrate), and
the best period for ingestion is 2–3 h before competing.
Conclusions. The variety of results makes it difficult to draw clear conclusions about nitrate supplementation
among endurance sports performance athletes. Given the plethora of studies connecting vascular NO bioavailability with
markers of vascular health such as blood pressure and endothelial function, further exploration of this topic is clearly
warranted, to clarify the mechanisms underpinning intra and inter compartmental nitrogen-oxide chemistry and resultant
physiological outcomes, such as cardiovascular health and exercise in larger more heterogeneous groups of subjects.
References
Bailey, S. J., Fulford, J., Vanhatalo, A., Winyard, P. G., Blackwell, J. R., DiMenna, F. J., Wilkerson, D. P., Benjamin, N., &
Jones, A. M. (2010). Dietary nitrate supplementation enhances muscle contractile efficiency during knee-extensor exercise in
humans. The American Physiological Society, 109(1), 135–148. doi:10.1152/japplphysiol.00046.2010
Campos, H. O., Drummond, L. R., Rodrigues, Q. T., Machado, F. S. M., 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. The British Journal of Nutrition, 119, 636–657. doi:10.1017/S0007114518000132
Dominguez, R., Cuenca, E., Mate-Munoz, J. L., García-Fernandez, P., Serra-Paya, N., Estevan, M. C. L., Herreros, P. V., &
Garnacho-Castano, 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
Jones, A. M. (2014). Dietary nitrate supplementation and exercise performance. Sports Medicine, 44(1), 35–45. doi:10.1007/s40279-
014-0149-y
Keywords: beetroot juice, nitrate, nitric oxide, endurance, protocols.