Sayer Ji
Founder of GreenMedInfo.com

Subscribe to our informative Newsletter & get two FREE E-Books

Our newsletter serves 500,000 with essential news, research & healthy tips, daily.

Depression: 21st Century Solutions + The Dark Side of Wheat

Article Publish Status: FREE
Abstract Title:

Beetroot juice supplementation speeds O2 uptake kinetics and improves exercise tolerance during severe-intensity exercise initiated from an elevated metabolic rate.

Abstract Source:

Am J Physiol Regul Integr Comp Physiol. 2013 Dec 15 ;305(12):R1441-50. Epub 2013 Oct 2. PMID: 24089377

Abstract Author(s):

Brynmor C Breese, Melitta A McNarry, Simon Marwood, Jamie R Blackwell, Stephen J Bailey, Andrew M Jones

Article Affiliation:

Brynmor C Breese

Abstract:

Recent research has suggested that dietary nitrate (NO3(-)) supplementation might alter the physiological responses to exercise via specific effects on type II muscle. Severe-intensity exercise initiated from an elevated metabolic rate would be expected to enhance the proportional activation of higher-order (type II) muscle fibers. The purpose of this study was, therefore, to test the hypothesis that, compared with placebo (PL), NO3(-)-rich beetroot juice (BR) supplementation would speed the phase II VO2 kinetics (τ(p)) and enhance exercise tolerance during severe-intensity exercise initiated from a baseline of moderate-intensity exercise. Nine healthy, physically active subjects were assigned in a randomized, double-blind, crossover design to receive BR (140 ml/day, containing ~8 mmol of NO3(-)) and PL (140ml/day, containing ~0.003 mmol of NO3(-)) for 6 days. On days 4, 5, and 6 of the supplementation periods, subjects completed a double-step exercise protocol that included transitions from unloaded to moderate-intensity exercise (U→M) followed immediately by moderate to severe-intensity exercise (M→S). Compared with PL, BR elevated resting plasma nitrite concentration (PL: 65 ± 32 vs. BR: 348 ± 170 nM, P<0.01) and reduced the VO2τ(p) in M→S (PL: 46 ± 13 vs. BR: 36 ± 10 s, P<0.05) but not U→M (PL: 25 ± 4 vs. BR: 27 ± 6 s, P>0.05). During M→S exercise, the faster VO2 kinetics coincided with faster near-infrared spectroscopy-derived muscle [deoxyhemoglobin] kinetics (τ; PL: 20 ± 9 vs. BR: 10 ± 3 s, P<0.05) and a 22% greater time-to-task failure (PL: 521± 158 vs. BR: 635 ± 258 s, P<0.05). Dietary supplementation with NO3(-)-rich BR juice speeds VO2 kinetics and enhances exercise tolerance during severe-intensity exercise when initiated from an elevated metabolic rate.

Study Type : Human Study

Print Options


Sayer Ji
Founder of GreenMedInfo.com

Subscribe to our informative Newsletter & get two FREE E-Books

Our newsletter serves 500,000 with essential news, research & healthy tips, daily.

Depression: 21st Century Solutions + The Dark Side of Wheat

This website is for information purposes only. By providing the information contained herein we are not diagnosing, treating, curing, mitigating, or preventing any type of disease or medical condition. Before beginning any type of natural, integrative or conventional treatment regimen, it is advisable to seek the advice of a licensed healthcare professional.

© Copyright 2008-2019 GreenMedInfo.com, Journal Articles copyright of original owners, MeSH copyright NLM.