New Study Finds Dietary Nitrate In Beetroot Juice Increases Muscle Force During Exercise

It is well-established that consuming dietary nitrate can improve exercise performance, by increasing endurance and enhancing high-intensity exercise. However, the underlying mechanisms of how this occurs and how our bodies convert dietary nitrate into nitric oxide, which is utilized by our cells, is not fully understood.

In order to gain further insight into this process, researchers from the University of Exeter and the National Institutes of Health in the United States conducted a study on ten healthy volunteers.

The study aimed to trace the distribution of ingested nitrate in the body and to determine where the dietary nitrate was active. To do this, the researchers measured the levels of nitrate in the participants’ saliva, blood, muscle, and urine before and after they ingested nitrate, and then asked them to perform a high-intensity leg exercise.

Results Of The Study

A study was conducted to examine the effects of nitrate intake on muscle force. The results of the study as per ‘Science Daily‘ showed that an hour after the nitrate was taken, there was a significant increase in nitrate levels in the muscle.

Participants consumed nitrate and then performed a specific exercise involving the quadriceps muscle. The researchers found that the nitrate intake led to an increase in nitrate levels in the muscle and resulted in a 7% increase in muscle force during the exercise, compared to when the participants took a placebo.

This study provides important clues on the mechanisms behind the effects of dietary nitrate on exercise performance and how the body processes this nutrient.

Andy Jones, Professor of Applied Physiology at the University of Exeter, said: “Our research has already provided a large body of evidence on the performance-enhancing properties of dietary nitrate, commonly found in beetroot juice. Excitingly, this latest study provides the best evidence to date on the mechanisms behind why dietary nitrate improves human muscle performance.”

Previous research had found that consuming nitrate-rich foods can lead to an increase of nitrate in body tissue and fluid. However, the exact location of this increase and how it contributes to enhanced exercise performance was not well understood. In a new study, researchers used a tracer to accurately track the distribution of nitrate in the body after ingestion.

This study provided the first direct evidence that nitrate levels in muscle play a crucial role in exercise performance, possibly by functioning as a source of nitric oxide. The results of this study have significant implications not only for the field of exercise science but also for medical areas that focus on treating neuromuscular and metabolic diseases related to nitric oxide deficiency.

The study was conducted in collaboration with researchers from the University of Queensland in Australia, as part of the QUEX partnership with the University of Exeter.

The Benefits And Risks Of Beetroot Juice Consumption

Beetroot juice (BRJ) is a popular beverage among athletes and fitness enthusiasts as it contains a high concentration of nitrate, which is known to enhance sports performance. Nitrate is converted in the human body to nitrite and subsequently to nitric oxide (NO), a compound that has a vasodilatory effect, resulting in reduced blood pressure and increased oxygen- and nutrient delivery to the active muscle. The global beetroot juice market is also growing at a steady rate. Below are some of the benefits and risks associated with beetroot juice consumption.

Benefits Of Beetroot Juice Consumption

• Improved sports performance: Studies have shown that BRJ consumption can improve endurance and high-intensity exercise performance.
• Reduced blood pressure: The nitric oxide in BRJ has a vasodilatory effect, which leads to a decrease in blood pressure.
• Increased oxygen- and nutrient delivery to active muscles.

Risks Of Beetroot Juice Consumption

Nitrate intake contributes to the endogenous formation of N-nitroso compounds (NOCs), a class of chemical carcinogens. Once ingested, about 20% of the nitrate is converted to nitrite by bacteria that are present in the oral cavity. Nitrous acid (HNO2) is formed when nitrite is transformed in the acidic environment of the stomach. N2O3 and water are released from the reaction of two molecules of HNO2, and the formed N2O3 reacts with amines to nitrosamines, a specific subgroup of NOCs.

Protonation of HNO2 followed by a reaction with amides can also lead to the formation of nitrosamides. Reactive intermediates, formed by these NOC’s, can bind to DNA. If these DNA lesions are not repaired, mutations can occur which are potentially involved in the process of cancer development.