The effects of dietary nitrate ingestion on physical performance tests in 50–65 years old postmenopausal women: A pilot randomized, double-blind, placebo-controlled, and crossover study

• Published in: Clinical nutrition (Edinburgh, Scotland) Scotland), 2024-07, Vol.43 (7), p.1642-1646
• Main Authors: Benjamim, Cicero Jonas R., Lopes da Silva, Leonardo Santos, da Silva Gonçalves, Leonardo, Tasinafo Júnior, Márcio Fernando, Spellanzon, Bruno, Rebelo, Macario Arosti, Tanus-Santos, José E., Bueno Júnior, Carlos Roberto
• Format: Article
• Language: English
• Subjects: Aged; Aging; Beta vulgaris - chemistry; Cross-Over Studies; Dietary Supplements; Double-Blind Method; Exercise; Female; Fruit and Vegetable Juices; Hand Strength - physiology; Humans; Middle Aged; Nitrates - administration & dosage; Nitrates - blood; Nitric oxide; Nitrite; Physical capacity; Physical Functional Performance; Pilot Projects; Postmenopause
• ISSN: 0261-5614; 1532-1983; 1532-1983
• DOI: 10.1016/j.clnu.2024.05.031

The post-menopausal period represents a noteworthy stage in a woman's life characterized by hormonal shifts that can influence diverse biological processes encompassing energy metabolism and physical performance. NO3− effects on physical performance in 50–65 years old postmenopausal women after short-term supplementation remain unknown. This is a randomized, double-blind, placebo-controlled, crossover study. After two sessions in non-consecutive days of familiarization tests, fifteen post-menopausal women aged between 50 and 65 were enrolled in this study. The trial consisted of two eight-day arms: a) NO3− −70 mL of beetroot juice (BRJ) with ˜400 mg of NO3−, and b) placebo (PLA) −70 mL of BRJ NO3− depleted. Both interventions were obtained from the same manufacturer's product, presenting the same organoleptic properties. After this period, five physical performance tests (handgrip strength, arm curl, sit-to-stand, agility and dynamic balance and 6-min walk test (6MWT)) were applied. Fourteen participants completed all experimental protocols, including a minimum seven-day washout period between protocols. NO2− plasma concentrations were consistently elevated in the NO3− condition at 0.41 (0.40) μM compared to the PLA at 0.18 (0.18) μM (p  0.05). Our findings suggest benefits in the physical performance of activities with longer durations, indicating that the adaptation caused by ingestion of NO3− may be related to the cardiorespiratory capacity. NO2−/NO3− = nitrite/nitrate; 6MWT(M) = 6-min walk test; PLA = placebo. [Display omitted]