Ergogenic effects of beetroot juice supplementation on neuromuscular function and simulated combat demands in elite female taekwondo athletes

Beetroot juice supplementation has been widely examined across various sport disciplines due to its potential ergogenic effects. However, evidence regarding its impact on combat sports particularly in female athletes remains limited. The aim of this study was to evaluate the acute effects of beetroot juice supplementation on simulated taekwondo combat performance and neuromuscular function in elite female taekwondo athletes. Seven elite female Olympic taekwondo athletes (age: 20.3 ± 3.7 years), participated in a randomized, double-blind, placebo-controlled study consisting of two experimental trials). Each trial involved the consumption of either 140 mL of beetroot juice (which contains 12.8 mmol NO₃⁻) or 140 mL of a placebo (with 0.08 mmol NO₃⁻) followed by a simulated taekwondo combat session and assessments of neuro-muscular function (i.e., vertical jump and visual cognitive performance). In addition, metabolic (i.e., blood lactate), and perceptual responses (i.e., rate of perceived exertion) were measured before, after, and 3 minutes post-combat. No significant differences during the simulated taekwondo combat (e.g., attack time; p = 0.531–0.989; ηp² = 0.01–0.05), neuromuscular function battery (p = 0.302-0.700; ηp² = 0.02-0.04), blood lactate concentrations (p = 0.705; ηp² = 0.13), or rate of perceived exertion values (RPE) (p = 0.717; ηp² = 0.12) were obtained between beetroot juice and placebo conditions. Acute ingestion of beetroot juice (140 mL) did not enhance simulated combat performance or neuromuscular function in female Olympic taekwondo athletes.

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