Effects of Nitrate Supplementation on Exercise Performance in Humans: A Narrative Review.

Matjaž Macuh,Bojan Knap

doi:10.3390/nu13093183

Abstract

Nitrates have become increasingly popular for their potential role as an ergogenic aid. The purpose of this article was to review the current scientific evidence of nitrate supplementation on human performance. The current recommendation of nitrate supplementation is discussed, as well as possible health complications associated with nitrate intake for athletes, and dietary strategies of covering nitrate needs through sufficient intake of nitrate-rich foods alone are presented. Pubmed, Scopus, and Web of Science were searched for articles on the effects of nitrate supplementation in humans. Nitrates are an effective ergogenic aid when taken acutely or chronically in the range of ~5–16.8 mmol (~300–1041 mg) 2–3 h before exercise and primarily in the case of exercise duration of ~10–17 min in less trained individuals (VO2max < 65 mL/kg/min). Nitrate needs are most likely meet by ingesting approximately 250–500 g of leafy and root vegetables per day; however, dietary supplements might represent a more convenient and accurate way of covering an athlete’s nitrate needs. Athletes should refrain from mouthwash usage when nitrate supplementation benefits are desired. Future research should focus on the potential beneficial effects of nitrate supplementation on brain function, possible negative impacts of chronic nitrate supplementation through different nitrate sources, and the effectiveness of nitrate supplementation on strength and high-intensity intermittent exercise.

Highlights

Nitric oxide (NO) is a signaling molecule involved in numerous vascular and cellular functions, such as cellular respiration, vasodilation, and angiogenesis
Athletes should refrain from mouthwash usage when nitrate supplementation benefits are desired
Oral intake of L-citrulline as a dietary supplement increases the bioavailability of L-arginine to a greater extent than supplementation with L-arginine, as it is directly transported to the kidneys where it is converted to L-arginine, whereas L-arginine is subjected to catabolism via the enzyme arginase [2]

Summary

Introduction

Nitric oxide (NO) is a signaling molecule involved in numerous vascular and cellular functions, such as cellular respiration, vasodilation, and angiogenesis. An extensive review of the literature on the effects of L-arginine and L-citrulline is beyond the scope of this article. It is worth noting that the positive effects of increased NO bioavailability may be induced through NO3− supplementation but potentially through L-arginine and L-citrulline supplementation as well. NO3− supplementation and its effects on different types of exercise performance have gained attention in the past 2 decades. The purpose of this narrative review was to review the current scientific literature on the effects of NO3− supplementation on human performance, mechanisms by which NO3− may act as an ergogenic aid, and whether NO3− supplements are needed. Studies completed in animal models or individuals with certain medical conditions were excluded from the review

Nitrates

Nitrates and Exercise Performance

Main Findings

Findings

Conclusions