A Single Dose of Beetroot Juice Enhances Cycling Performance in Simulated Altitude

Muggeridge, David J.; Howe, Christopher C. F.; Spendiff, Owen; Pedlar, Charles; James, Philip E.; Easton, Chris

Abstract

INTRODUCTION: Increasing nitric oxide bioavailability via supplementation with nitrate-rich beetroot juice (BR) has been shown to attenuate the negative effect of hypoxia on peripheral oxygen saturation and exercise tolerance.

PURPOSE: We investigated the effects of a single dose of concentrated BR on the physiological responses to submaximal exercise and time trial (TT) performance in trained cyclists exposed to moderate simulated altitude (approximately 2500 m).

METHODS: Nine competitive amateur male cyclists (age, 28 ± 8 yr; V˙O2peak at altitude, 51.9 ± 5.8 mL·kg·min) completed four exercise trials consisting of an initial graded test to exhaustion and three performance trials on a cycle ergometer. The performance trials comprised 15 min of submaximal steady-state exercise at 60% maximum work rate and a 16.1-km TT. The second and third trials were preceded by ingestion of either 70 mL of BR or nitrate-depleted BR (PLA) 3 h before exercise.

RESULTS: Plasma nitrate (PLA, 39.1 ± 3.5 µM; BR, 150.5 ± 9.3 µM) and nitrite (PLA, 289.8 ± 27.9 nM; BR, 678.1 ± 103.5 nM) measured immediately before exercise were higher after ingestion of BR compared with that after PLA (P < 0.001, P = 0.004). V˙O2 during steady-state exercise was lower in the BR trial (2542 ± 114 mL·min) than that in the PLA trial (2727 ± 85 mL·min, P = 0.049). TT performance was significantly faster after BR (1664 ± 14 s) than that after PLA (1702 ± 15 s, P = 0.021).

CONCLUSION: A single dose of BR lowered V˙O2 during submaximal exercise and enhanced TT performance of trained cyclists in normobaric hypoxia. Consequently, ingestion of BR may be a practical and effective ergogenic aid for endurance exercise at altitude.

Citation

Muggeridge, D. J., Howe, C. C. F., Spendiff, O., Pedlar, C., James, P. E., & Easton, C. (2014). A Single Dose of Beetroot Juice Enhances Cycling Performance in Simulated Altitude. Medicine and Science in Sports and Exercise, 46(1), 143-150. https://doi.org/10.1249/mss.0b013e3182a1dc51

• Journal Article Type: Article
• Acceptance Date: Jun 1, 2013
• Publication Date: 2014-01
• Deposit Date: Oct 22, 2020
• Journal: Medicine & Science in Sports & Exercise
• Print ISSN: 0195-9131
• Electronic ISSN: 1530-0315
• Publisher: Lippincott, Williams & Wilkins
• Peer Reviewed: Peer Reviewed
• Volume: 46
• Issue: 1
• Pages: 143-150
• DOI: https://doi.org/10.1249/mss.0b013e3182a1dc51
• Public URL: http://researchrepository.napier.ac.uk/Output/2694148