Recent evidence indicates that elevating plasma nitrites through dietary nitrates (NO3−) supplementation is associated with enhanced muscle efficiency, fatigue resistance and performance. Beetroot (in various forms) is the dominant source of dietary NO3− primarily due to its vast availability and the simple form of preparation suitable for final consumption. After a few years of research and experimentation, our scientific team identified alternative source rich with dietary NO3− as possible nitric oxide precursor, amaranth (Amaranthus hypochondriacus) with a standardized concentration 9–11% of NO3−. This study aimed to evaluate the effect of single-dose (±400 mg of dietary NO3−) and long-term (6 days) supplementation of amaranth concentrate derived dietary NO3− on aerobic capacity in physically active young people. We conducted a randomized, double-blind, placebo-controlled human study. Thirteen healthy and physically active young male participants were randomized into experimental and placebo groups. The aerobic capacity was tested during increasing cycling exercise (ICE) with pulmonary gas exchange recording and analysis. The peak power of the ICE, the maximum oxygen consumption and the first ventilatory threshold were significantly increased after long-term consumption of dietary amaranth (from 4.44 ± 0.50 to 4.55 ± 0.43 W/kg; from 37.7 ± 2.7 to 41.2 ± 5.4 mL/kg/min and from 178.6 ± 30.3 to 188.6 ± 35.2 W, p < 0.05; respectively) in experimental group. Long-term (6 days) use of dietary NO3− from amaranth may improve the aerobic capacity during ICE in young physically active male persons. It can be recommended as the nutritional supplement during last week of preparation for competition in endurance events.

中文翻译：

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苋菜（Amaranthus hypochondriacus）膳食硝酸盐对身体活跃的年轻人有氧能力的影响

最近的证据表明，通过膳食硝酸盐 (NO3−) 补充剂提高血浆亚硝酸盐与增强肌肉效率、抗疲劳性和性能有关。甜菜根（以各种形式）是膳食 NO3− 的主要来源，这主要是由于其广泛的可用性和适合最终消费的简单制备形式。经过几年的研究和实验，我们的科学团队确定了富含膳食 NO3− 的替代来源，作为可能的一氧化氮前体，苋菜 (Amaranthus hypochondriacus) 的标准浓度为 9–11% 的 NO3−。本研究旨在评估单剂量（±400 毫克膳食 NO3−）和长期（6 天）补充苋菜浓缩物衍生膳食 NO3− 对身体活跃的年轻人有氧能力的影响。我们进行了一项随机、双盲、安慰剂对照的人体研究。13 名健康和身体活跃的年轻男性参与者被随机分为实验组和安慰剂组。通过肺气体交换记录和分析，在增加自行车运动 (ICE) 期间测试有氧能力。长期食用苋菜后，ICE的峰值功率、最大耗氧量和第一通气阈值显着增加（从4.44±0.50到4.55±0.43 W/kg；从37.7±2.7到41.2±5.4 mL/ kg/min 和从 178.6 ± 30.3 到 188.6 ± 35.2 W，分别为 p < 0.05；在实验组中。长期（6 天）使用来自苋菜的膳食 NO3− 可以提高年轻身体活跃男性在 ICE 期间的有氧能力。