What is the role of nitric oxide in sports?
Nitric oxide is a short-lived messenger molecule that plays a role in regulating vascular tone, blood flow, and some muscle contraction processes. Increasing its availability can facilitate the dilation of blood vessels and blood delivery to the active tissue.
This mechanism does not mean a definite increase in the performance of all athletes. The type of test, level of preparation, dose, time of consumption and individual differences affect the result.
Two main pathways of NO production
In the enzyme-dependent pathway, L-arginine is converted to NO and L-citrulline with the help of nitric oxide synthase. This pathway is dependent on oxygen and cellular conditions.
In the nitrate-nitrite-NO pathway, dietary nitrate is converted into nitrite after absorption and salivary circulation by oral bacteria, and then into NO under suitable conditions. This pathway can become more important in a low-oxygen and acidic environment.
Nitrate sources and functional evidence
Leafy green vegetables and beets are the main sources of dietary nitrate. Systematic reviews report a small and condition-dependent effect on some indicators such as time to fatigue, muscular endurance or power; But the result is not the same for time trial, highly trained people and all disciplines.
The 2025 umbrella review also showed mixed effects and assessed the methodological quality of many reviews as low. Therefore, the expectation should be realistic and the test should be done in training, before the competition.
Food nitrate is not the same as nitrite and nitrosamine
Nitrate in vegetables is obtained along with vitamin C and polyphenols, and its nutritional context is not the same as that of processed meats. Nitrosamines can form in the presence of nitrites, amines, and conditions such as high heat or improper storage.
Simply dividing all nitrates into "good" or "bad" is not accurate; The source, dose, food composition and processing method are important. Drinking water must meet safety standards.
Practical application and precautions
Concentrated nitrate products may lower blood pressure and may be incompatible with medical conditions or certain medications. People with heart disease, kidney disease or low blood pressure and users of related drugs should consult a doctor before use.
Strong antibacterial mouthwash can disrupt the conversion of nitrate to nitrite. Any supplemental strategy should be tested first in training and should not take the place of sleep, adequate nutrition and training program.
