Dose-Response Effect of Dietary Nitrate on Muscle Contractility and Blood Pressure in Older Subjects: A Pilot Study.
We have recently demonstrated that dietary nitrate, a source of nitric oxide (NO) via the nitrate → nitrite → NO enterosalivary pathway, can improve muscle contractility in healthy older men and women. Nitrate ingestion has also been shown to reduce blood pressure in some, but not all, studies of ol...
| Publicado en: | Journals of Gerontology Series A: Biological Sciences & Medical Sciences Vol. 76; no. 4; pp. 591 - 599 |
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| Autores principales: | , , , , , |
| Formato: | research randomized controlled trial Journal Article |
| Publicado: |
Oxford University Press / USA
Apr2021
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| Acceso en línea: | Ver este registro en EBSCOhost |
| fields | @attributes: recordID: 1 pdfLink: plink: https://search.ebscohost.com/login.aspx?direct=true&db=ccm&AN=149634671&site=ehost-live header: @attributes: shortDbName: ccm uiTerm: 149634671 longDbName: CINAHL Complete uiTag: AN controlInfo: bkinfo: dissinfo: jinfo: jid: 10795006 JGA jtl: Journals of Gerontology Series A: Biological Sciences & Medical Sciences issn: 10795006 maglogo: N pubinfo: dt: Apr2021 vid: 76 iid: 4 pid: 622 pub: Oxford University Press / USA artinfo: ui: 149634671 149634671 NLM33301009 149634671 10.1093/gerona/glaa311 NLM33301009 149634671 ppf: 591 ppct: 8 formats: tig: atl: Dose-Response Effect of Dietary Nitrate on Muscle Contractility and Blood Pressure in Older Subjects: A Pilot Study. aug: au: Gallardo, Edgar J Gray, Derrick A Hoffman, Richard L Yates, Brandon A Moorthi, Ranjani N Coggan, Andrew R affil: Department of Kinesiology, School of Health and Human Sciences, Indiana University Purdue University Indianapolis sug: subj: Nitrates Pharmacodynamics Dose-Response Relationship, Drug Muscle Contraction Drug Effects Nitric Oxide Analysis Nitric Oxide Metabolism Beet Pilot Studies Monitoring, Physiologic Methods Male Research Subjects Human Double-Blind Studies Phytochemicals Pharmacodynamics Female Aged Breath Tests Methods Dietary Supplements Blood Pressure Drug Effects Comparative Studies Multicenter Studies Randomized Controlled Trials Evaluation Research Validation Studies Aged: 65+ years Male Female ab: We have recently demonstrated that dietary nitrate, a source of nitric oxide (NO) via the nitrate → nitrite → NO enterosalivary pathway, can improve muscle contractility in healthy older men and women. Nitrate ingestion has also been shown to reduce blood pressure in some, but not all, studies of older individuals. However, the optimal dose for eliciting these beneficial effects is unknown. A pilot randomized, double-blind, placebo-controlled crossover study was therefore performed to determine the effects of ingesting 3.3 mL/kg of concentrated beetroot juice containing 0, 200, or 400 µmol/kg of nitrate in 9 healthy older subjects (mean age 70 ± 1 years). Maximal knee extensor power (Pmax) and speed (Vmax) were measured ~2.5 hours after nitrate ingestion using isokinetic dynamometry. Blood pressure was monitored periodically throughout each study. Pmax (in W/kg) was higher (p < .05) after the lower dose (3.9 ± 0.4) compared to the placebo (3.7 ± 0.4) or higher dose (3.7 ± 0.4). Vmax (in rad/s) also tended to be higher (p = .08) after the lower dose (11.9 ± 0.7) compared to the placebo (10.8 ± 0.8) or higher dose (11.2 ± 0.8). Eight out of 9 subjects achieved a higher Pmax and Vmax after the lower versus the higher dose. These dose-related changes in muscle contractility generally paralleled changes in breath NO levels. No significant changes were found in systolic, diastolic, or mean arterial blood pressure. A lower dose of nitrate increases muscle speed and power in healthy older individuals, but these improvements are lost at a higher dose. Blood pressure, on the other hand, is not reduced even with a higher dose. pubtype: Academic Journal doctype: research randomized controlled trial Journal Article ougenre: Article language: English refInfo: holdings: @attributes: islocal: N |
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