Athletes often seek to use dietary supplements to increase performance during exercise. Among various supplements, much attention has been paid to beetroot in recent years. Beetroot is a source of carbohydrates, fiber, protein, minerals, and vitamins; also, it is a natural source of nitrate and associated with improved sports performance. Nitrates can the modification of skeletal muscle contractile proteins or calcium handling after translation. The time to reach the peak plasma nitrate is between 1 and 3 h after consumption of a single dose of nitrate. Nitrate is metabolized by conversion to nitrite and subsequently nitric oxide. Beetroot can have various effects on athletic performance through nitric oxide. Nitric oxide is an intracellular and extracellular messenger for regulating certain cellular functions and causes vasodilation of blood vessels and increases blood flow. Nitric oxide seems to be effective in improving athletic performance by increasing oxygen, glucose, and other nutrients for better muscle fueling. Nitric oxide plays the main role in anabolic hormones, modulates the release of several neurotransmitters and the major mediators of stress involved in the acute hypothalamic-pituitary-adrenal response to exercise. Beetroot is an important source of compounds such as ascorbic acid, carotenoids, phenolic acids, flavonoids, betaline, and highly active phenolics and has high antioxidant properties. Beetroot supplement provides an important source of dietary polyphenols and due to the many health benefits. Phytochemicals of Beetroot through signaling pathways inhibit inflammatory diseases. In this study, the mechanisms responsible for these effects were examined and the research in this regard was reviewed.

In sports competitions, the winning margin is decreasing and, in some cases the results of competitions may change by a fraction of a second due to the performance of athletes. Therefore, athletes are constantly looking for every benefit to improve sport performance. Some athletes maybe resort to dietary supplements (natural and organic resources) to provide these benefits (1). Dietary supplements are a significant option for the elite and recreational athletes to enhance their performance (2). Athletes are exposed to a variety of food products marketed with the claim of improving health, efficiency, and performance. However, few studies confirm these claims, and the affection and safety of these products are questioned (3).

There are many dietary supplements, however in recent years; special attention has been paid to beetroot (BR) supplements. BR is a source of carbohydrates, fiber, protein, vitamins, and minerals (sodium, potassium, calcium, and iron) (as shown in Table 1) (4–8) and among other foods rich in nitrate (NO3-) including spinach, celery, lettuce, and carrot juice has high NO3- (