Acute dietary nitrate supplementation does not augment submaximal forearm exercise hyperemia in healthy young men

Jin Kwang Kim, David J. Moore, David G. Maurer, Daniel B. Kim-Shapiro, Swati Basu, Michael P. Flanagan, Ann C. Skulas-Ray, Penny Kris-Etherton, David N. Proctor

Research output: Contribution to journalArticlepeer-review

36 Scopus citations

Abstract

Despite the popularity of dietary nitrate supplementation and the growing evidence base of its potential ergogenic and vascular health benefits, there is no direct information about its effects on exercising limb blood flow in humans. We hypothesized that acute dietary nitrate supplementation from beetroot juice would augment the increases in forearm blood flow, as well as the progressive dilation of the brachial artery, during graded handgrip exercise in healthy young men. In a randomized, double-blind, placebo-controlled crossover study, 12 young (22 ± 2 years) healthy men consumed a beetroot juice (140 mL Beet-It Sport, James White Juice Company) that provided 12.9 mmol (0.8 g) of nitrate or placebo (nitrate-depleted Beet-It Sport) on 2 study visits. At 3 h postconsumption, brachial artery diameter, flow, and blood velocity were measured (Doppler ultrasound) at rest and during 6 exercise intensities. Nitrate supplementation raised plasma nitrate (19.5-fold) and nitrite (1.6-fold) concentrations, and lowered resting arterial pulse wave velocity (PWV) versus placebo (all p < 0.05), indicating absorption, conversion, and a biological effect of this supplement. The supplement-associated lowering of PWV was also negatively correlated with plasma nitrite (r = –0.72, p = 0.0127). Despite these systemic effects, nitrate supplementation had no effect on brachial artery diameter, flow, or shear rates at rest (all p ≥ 0.28) or during any exercise workload (all p ≥ 0.18). These findings suggest that acute dietary nitrate supplementation favorably modifies arterial PWV, but does not augment blood flow or brachial artery vasodilation during nonfatiguing forearm exercise in healthy young men.

Original languageEnglish (US)
Pages (from-to)122-128
Number of pages7
JournalApplied Physiology, Nutrition and Metabolism
Volume40
Issue number2
DOIs
StatePublished - Oct 16 2014
Externally publishedYes

Keywords

  • Inorganic nitrate
  • Pulse wave velocity
  • Vascular function

ASJC Scopus subject areas

  • Endocrinology, Diabetes and Metabolism
  • Physiology
  • Nutrition and Dietetics
  • Physiology (medical)

Fingerprint

Dive into the research topics of 'Acute dietary nitrate supplementation does not augment submaximal forearm exercise hyperemia in healthy young men'. Together they form a unique fingerprint.

Cite this