Dietary nitrate supplementation in cardiovascular health: an ergogenic aid or exercise therapeutic?

Abstract

Oral consumption of inorganic nitrate, which is abundant in green leafy vegetables and roots, has been shown to increase circulating plasma nitrite concentration, which can be converted to nitric oxide in low oxygen conditions. The associated beneficial physiological effects include a reduction in blood pressure, modification of platelet aggregation, and increases in limb blood flow. There have been numerous studies of nitrate supplementation in healthy recreational and competitive athletes; however, the ergogenic benefits are currently unclear due to a variety of factors including small sample sizes, different dosing regimens, variable nitrate conversion rates, the heterogeneity of participants' initial fitness levels, and the types of exercise tests used. In clinical populations, the study results seem more promising, particularly in patients with cardiovascular diseases who typically present with disruptions in the ability to transport oxygen from the atmosphere to working tissues and reduced exercise tolerance. Many of these disease-related, physiological maladaptations, including endothelial dysfunction, increased reactive oxygen species, reduced tissue perfusion, and muscle mitochondrial dysfunction, have been previously identified as potential targets for nitric oxide restorative effects. This review is the first of its kind to outline the current evidence for inorganic nitrate supplementation as a therapeutic intervention to restore exercise tolerance and improve quality of life in patients with cardiovascular diseases. We summarize the factors that appear to limit or maximize its effectiveness and present a case for why it may be more effective in patients with cardiovascular disease than as ergogenic aid in healthy populations.

The Effect of Dietary Inorganic Nitrate Supplementation on Cardiac Function during Submaximal Exercise in Men with Heart Failure with Reduced Ejection Fraction (HFrEF): A Pilot Study

“…Herein, we report that oral inorganic nitrate supplementation resulted in a greater increase in Q in two (out of three) stages of discontinuous incremental exercise. These differences were seen specifically during the higher intensity workloads, which is in line with previous work indicating the effects of nitrate supplementation are more pronounced in low oxygen conditions [13]. This finding is in agreement with an earlier study by Zamani et al in which patients with HFpEF demonstrated increases in Q (measured with echocardiography) following a single acute dose of 12.9mmol inorganic nitrate [17].…”

“…Inorganic nitrate supplementation is an established intervention for increasing NO bioavailability in both healthy and diseased populations [11,12]. While previous studies have demonstrated improvements in exercise performance and vascular outcomes in diverse clinical cohorts, the majority of studies in HFrEF have indicated that supplementation has a minimal effect [13][14][15][16] However, evidence in HFpEF suggests the potential for nitrate (and nitrite) supplementation to improve systemic vascular resistance (SVR) and cardiac output (CO) [10,17]. To our knowledge, no study to date has examined the effects of supplementation on measures of cardiac function during exercise.…”

The use of topical Nitrosomonas eutropha for cosmetic improvement of facial wrinkles

“…As an ammonia‐oxidizing bacteria (AOB), Nitrosomonas eutropha utilizes ammonia from sweat to generate nitrite and nitric oxide. Studies have shown that nitrite and nitric oxide are associated with beneficial physiological effects including vasodilation, anti‐inflammatory properties, improved wound healing, and reduced blood pressure . In pre‐clinical studies, Nitrosomonas eutropha led to a reduction in pathogenic bacteria on the skin (eg, Propionibacterium acnes ), as well as improved skin healing .…”

Inorganic nitrate supplementation and exercise. Is skeletal muscle involved in the heavy lifting?

“…A beneficial effect also appears more likely following chronic dosing regimens in less conditioned individuals (including those with cardiovascular impairments) employing higher intensity activities which utilize fast twitch muscle fibres (Woessner et al . ).…”

“…In healthy human studies the results are mixed with meta-analyses reporting overall no benefit for maximal graded exercise and time trial performance testing, but likely a benefit in time to exhaustion tests. A beneficial effect also appears more likely following chronic dosing regimens in less conditioned individuals (including those with cardiovascular impairments) employing higher Perspectives J Physiol 597.23 intensity activities which utilize fast twitch muscle fibres (Woessner et al 2018).…”