title: Effects of Beetroot Juice Supplementation on Cardiorespiratory Endurance in Athletes. A Systematic Review.
abstract: Athletes use nutritional supplementation to enhance the effects of training and achieve improvements in their athletic performance. Beetroot juice increases levels of nitric oxide (NO), which serves multiple functions related to increased blood flow, gas exchange, mitochondrial biogenesis and efficiency, and strengthening of muscle contraction. These biomarker improvements indicate that supplementation with beetroot juice could have ergogenic effects on cardiorespiratory endurance that would benefit athletic performance. The aim of this literature review was to determine the effects of beetroot juice supplementation and the combination of beetroot juice with other supplements on cardiorespiratory endurance in athletes. A keyword search of DialNet, MedLine, PubMed, Scopus and Web of Science databases covered publications from 2010 to 2016. After excluding reviews/meta-analyses, animal studies, inaccessible full-text, and studies that did not supplement with beetroot juice and adequately assess cardiorespiratory endurance, 23 articles were selected for analysis. The available results suggest that supplementation with beetroot juice can improve cardiorespiratory endurance in athletes by increasing efficiency, which improves performance at various distances, increases time to exhaustion at submaximal intensities, and may improve the cardiorespiratory performance at anaerobic threshold intensities and maximum oxygen uptake (VO2max). Although the literature shows contradictory data, the findings of other studies lead us to hypothesize that supplementing with beetroot juice could mitigate the ergolytic effects of hypoxia on cardiorespiratory endurance in athletes. It cannot be stated that the combination of beetroot juice with other supplements has a positive or negative effect on cardiorespiratory endurance, but it is possible that the effects of supplementation with beetroot juice can be undermined by interaction with other supplements such as caffeine.
authors.affiliation: College of Health Sciences, University Alfonso X El Sabio University, Madrid 29651, Spain. rdomiher@uax.es.
authors.forename: Raúl
authors.initials: R
authors.lastname: Domínguez
authors.affiliation: Tecnocampus, College of Health Sciences, University of Pompeu Fabra, Mataró-Maresme, Barcelona 08302 Spain. educuen@hotmail.com.
authors.forename: Eduardo
authors.initials: E
authors.lastname: Cuenca
authors.affiliation: College of Health Sciences, University Alfonso X El Sabio University, Madrid 29651, Spain. jmatmuo@uax.es.
authors.forename: José Luis
authors.initials: JL
authors.lastname: Maté-Muñoz
authors.affiliation: College of Health Sciences, University Alfonso X El Sabio University, Madrid 29651, Spain. pablgafe@uax.es.
authors.forename: Pablo
authors.initials: P
authors.lastname: García-Fernández
authors.affiliation: Tecnocampus, College of Health Sciences, University of Pompeu Fabra, Mataró-Maresme, Barcelona 08302 Spain. nserra@tecnocampus.cat.
authors.forename: Noemí
authors.initials: N
authors.lastname: Serra-Paya
authors.affiliation: College of Health Sciences, University Alfonso X El Sabio University, Madrid 29651, Spain. mloza@myuax.com.
authors.forename: María Carmen Lozano
authors.initials: MC
authors.lastname: Estevan
authors.affiliation: College of Health Sciences, University Alfonso X El Sabio University, Madrid 29651, Spain. pveigher@uax.es.
authors.forename: Pablo Veiga
authors.initials: PV
authors.lastname: Herreros
authors.affiliation: Tecnocampus, College of Health Sciences, University of Pompeu Fabra, Mataró-Maresme, Barcelona 08302 Spain. mgarnacho@escs.tecnocampus.cat.
authors.forename: Manuel Vicente
authors.initials: MV
authors.lastname: Garnacho-Castaño
mesh_terms: D056352:Athletes; D027461:Beta vulgaris / Q000737:chemistry*; D000072599:Cardiorespiratory Fitness; D016208:Databases, Factual; D000067030:Fruit and Vegetable Juices; D006801:Humans; D015201:Meta-Analysis as Topic; D010101:Oxygen Consumption; D058573:Performance-Enhancing Substances; D010807:Physical Endurance; D018517:Plant Roots / Q000737:chemistry*
chemical_list: D058573:Performance-Enhancing Substances
keywords: exercise; nitric oxide; nutrition; physical activity; sport