Related Experiment Video
Updated: Jun 3, 2026
07:19
Preparation of Rat Skeletal Muscle Homogenates for Nitrate and Nitrite Measurements
Published on: July 29, 2021
Acute dietary nitrate supplementation improves cycling time trial performance
Katherine E Lansley1, Paul G Winyard, Stephen J Bailey
1Sport and Health Sciences, College of Life and Environmental Sciences, St Luke's Campus, University of Exeter, Exeter, United Kingdom.
Medicine and Science in Sports and Exercise
|April 8, 2011
Summary
Dietary nitrate supplementation, found in beetroot juice, enhances cycling performance by increasing power output without affecting oxygen consumption. This leads to significant improvements in both short and long-distance time trials for competitive cyclists.
Area of Science:
- Sports Science
- Nutritional Physiology
- Exercise Metabolism
Background:
- Dietary nitrate supplementation is known to reduce exercise oxygen cost and improve high-intensity exercise tolerance.
- Its effects on simulated competition performance in cyclists remain largely unexplored.
Purpose of the Study:
- To investigate the impact of acute dietary nitrate supplementation on power output (PO), oxygen consumption (VO2), and performance during 4-km and 16.1-km cycling time trials (TT).
Main Methods:
- Nine competitive male cyclists participated in a randomized, crossover study.
- Participants consumed beetroot juice (BR) or a nitrate-depleted placebo (PL) 2.5 hours before completing 4-km and 16.1-km cycling TTs.
Main Results:
- Beetroot juice supplementation significantly increased plasma nitrite levels.
- Mean power output was significantly higher during both 4-km and 16.1-km TTs with BR compared to PL.
- Cycling performance improved by 2.8% in the 4-km TT and 2.7% in the 16.1-km TT with BR supplementation.
Conclusions:
- Acute dietary nitrate supplementation via beetroot juice enhances cycling economy, indicated by higher power output at the same VO2.
- This supplementation strategy improves performance in both 4-km and 16.1-km cycling time trials.
Related Concept Videos
01:16Antianginal Drugs: Nitrates and β-Blockers
In cardiovascular health, antianginal drugs combat angina pectoris — a condition marked by chest pain owing to diminished blood flow to the heart.
Organic nitrates, such as nitroglycerin, play a pivotal role. Once metabolized, they liberate nitric oxide, a molecular marvel. Nitric oxide triggers guanylyl cyclase and augments cGMP production. This biochemical cascade orchestrates the relaxation of vascular smooth muscles, ushering in vasodilation and enhancing coronary blood flow. Administered...
Organic nitrates, such as nitroglycerin, play a pivotal role. Once metabolized, they liberate nitric oxide, a molecular marvel. Nitric oxide triggers guanylyl cyclase and augments cGMP production. This biochemical cascade orchestrates the relaxation of vascular smooth muscles, ushering in vasodilation and enhancing coronary blood flow. Administered...
01:202° Amines to N-Nitrosamines: Reaction with NaNO2
Secondary amines react with nitrous acid to form N-nitrosamines, as depicted in Figure 1. Nitrous acid, a weak and unstable acid, is formed in situ from an aqueous solution of sodium nitrite and strong acids, such as hydrochloric acid or sulfuric acid, in cold conditions. In the presence of an acid, the nitrous acid gets protonated. The subsequent loss of water results in the formation of the electrophile known as nitrosonium ion.
01:28Nitric Oxide Signaling Pathway
Nitric oxide (NO), an inorganic gas, acts as a potent second messenger in most animal and plant tissues. NO diffuses out of the cells that produce it and enters the neighboring cells to generate a downstream response. NO synthase (NOS) catalyzes NO production by the deamination of the amino acid arginine. There are three isoforms of NOS. Endothelial cells have endothelial NOS (eNOS), nerve and muscle cells have neuronal NOS (nNOS), and macrophages produce inducible NOS (iNOS) upon exposure to...
01:49The Nitrogen Cycle
Nitrogen atoms, present in all proteins and DNA, are recycled between abiotic and biotic components of the ecosystem. However, the primary form of nitrogen on Earth is nitrogen gas, which cannot be used by most animals and plants. Thus, nitrogen gas must first be converted into a usable form by nitrogen-fixing bacteria before it can be cycled through other living organisms. The use of nitrogen-containing fertilizers and animal waste products in human agriculture has greatly influenced the...