Nutrients (Sep 2022)

Effects of Dietary Nitrate Supplementation on Performance and Muscle Oxygenation during Resistance Exercise in Men

  • Rachel Tan,
  • Adam Pennell,
  • Katherine M. Price,
  • Sean T. Karl,
  • Noelle G. Seekamp-Hicks,
  • Keonabelle K. Paniagua,
  • Grant D. Weiderman,
  • Joanna P. Powell,
  • Luka K. Sharabidze,
  • Isabella G. Lincoln,
  • Justin M. Kim,
  • Madeleine F. Espinoza,
  • Maya A. Hammer,
  • Richie P. Goulding,
  • Stephen J. Bailey

DOI
https://doi.org/10.3390/nu14183703
Journal volume & issue
Vol. 14, no. 18
p. 3703

Abstract

Read online

The purpose of the current study was to assess the effects of acute and short-term nitrate (NO3−)-rich beetroot juice (BR) supplementation on performance outcomes and muscle oxygenation during bench press and back squat exercise. Fourteen recreationally active males were assigned in a randomized, double-blind, crossover design to supplement for 4 days in two conditions: (1) NO3−-depleted beetroot juice (PL; 0.10 mmol NO3− per day) and (2) BR (11.8 mmol NO3− per day). On days 1 and 4 of the supplementation periods, participants completed 2 sets of 2 × 70%1RM interspersed by 2 min of recovery, followed by one set of repetitions-to-failure (RTF) at 60%1RM for the determination of muscular power, velocity, and endurance. Quadriceps and pectoralis major tissue saturation index (TSI) were measured throughout exercise. Plasma [NO3−] and nitrite ([NO2−]) were higher after 1 and 4 days of supplementation with BR compared to PL (p p > 0.05). The number of RTF in bench press was 5% greater after acute BR ingestion compared to PL (PL: 23 ± 4 vs. BR: 24 ± 5, p p > 0.05). These data improve understanding on the ergogenic potential of BR supplementation during resistance exercise.

Keywords