Effects of chronic beetroot juice supplementation on maximum oxygen uptake, velocity associated with maximum oxygen uptake, and peak velocity in recreational runners: a double-blinded, randomized and crossover study

Eur J Appl Physiol. 2019 May;119(5):1043-1053. doi: 10.1007/s00421-019-04094-w. Epub 2019 Feb 12.

Abstract

Purpose: This study investigated the effects of chronic 3-day beetroot juice (BRJ) supplementation on maximum oxygen uptake (VO2max), velocity associated with VO2max(vVO2max), and peak velocity (Vpeak) in recreational runners.

Methods: Thirteen male recreational runners (age 28.2 ± 3.0 years, height 176.8 ± 0.1 cm, body mass 74.4 ± 9.5 kg) performed four tests on a treadmill in a randomized, double-blind, crossover design: two maximum incremental tests to determine VO2max and vVO2max, and two tests to determine Vpeak. Trials were performed following 3 days of supplementation of NO3--rich BRJ in natura (8.4 mmol NO3- day- 1) or BRJ NO3--depleted placebo (0.01 mmol NO3- day- 1), with the last dose being ingested 2 h before each test. During the tests, maximum heart rate (HRmax), maximal rating of perceived exertion (RPEmax), pre- and post-test glucose concentrations (Glucpre, Glucpost), and peak blood lactate concentration were determined.

Results: VO2max was higher following BRJ vs PLA (46.6 ± 6.4 vs 45.1 ± 5.8 mL kg- 1 min- 1; P = 0.022), as well as vVO2max (14.5 ± 0.8 vs 13.9 ± 1.0 km h- 1P = 0.024) and Vpeak (15.5 ± 1.1 vs 15.2 ± 1.2 km h- 1P = 0.038), with no differences in the other variables.

Conclusion: Consumption of NO3--rich BRJ in natura (8.4 mmol NO3- day- 1) once per day for 3 days improved VO2max, vVO2max and Vpeak in recreational runners without changing the other analyzed variables.

Keywords: Exercise nutritional science; Nitrate supplementation; Nitric oxide; Physical endurance; Running.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Adult
  • Beta vulgaris / chemistry*
  • Blood Glucose / analysis
  • Dietary Supplements
  • Double-Blind Method
  • Fruit and Vegetable Juices*
  • Heart Rate
  • Humans
  • Lactic Acid / blood
  • Male
  • Oxygen Consumption / drug effects*
  • Plant Extracts / administration & dosage
  • Plant Extracts / pharmacology*
  • Running / physiology*

Substances

  • Blood Glucose
  • Plant Extracts
  • Lactic Acid