Acute Effects of Beetroot Juice Ingestion on Cognitive Function and Neuromuscular Performance in Elite Female Taekwondo Athletes

Beetroot juice is a good source of nitrate (NO3-), which is a precursor of nitric oxide (NO) through the NO3- to nitrite (NO2-) to NO pathway (Lundberg et al., 2008). This pathway is thought to promote increased sarcoplasmic reticulum calcium release and re-uptake with ensuing enhancements in force output within type II muscle fibers (Hernandez et al., 2012), as well as increased neurotransmitter release (Esen et al., 2022) and attenuated muscle potassium efflux (Wylie et al., 2013) that could benefit neuromuscular performance. Consequently, it is thought that a minimum threshold may exist for dietary NO3- consumption of at least 5 mmol to enhance athletic performance (Senefeld et al., 2020). In turn, systematic reviews have documented that the use of beetroot juice supplementation enhances muscle strength and power-related attributes (Gonzalez et al., 2023), as well as performance in repeated high-intensity activity bouts (Alsharif et al., 2023; Dominguez et al., 2018). However, beetroot juice supplementation has been shown to have equivocal effects on neuromuscular performance specifically among individual sport athletes (e.g. taekwondo). Thus, the aim of this study was to determine the effects of acute beetroot juice ingestion (140 mL, 12.8 mmol NO3-) on neuromuscular performance in elite female taekwondo athletes.