Multiday Beetroot Juice Ingestion Improves Some Aspects of Neuromuscular Performance in Semi-Professional, Male Handball Players: A Randomized, Double-Blind, Placebo-Controlled, Crossover Study

The aim of this study was to examine the effects of multiday beetroot juice ingestion on neuromuscular performance in semiprofessional, male handball players. Twelve handball players competing in the second Spanish national division received 70 ml of beetroot juice (6.4 mmol of nitrate [NO3-]) or 70 ml of a placebo beetroot juice (0.04 mmol NO3-) for three consecutive days in a randomized, double-blind, crossover manner with a 1-week washout between conditions. Following supplementation in each condition, players completed a neuromuscular test battery involving handball throwing, isometric handgrip strength, countermovement jump, change-of-direction speed, and repeated-sprint assessments, with side effects also measured. Countermovement jump (4.7%; p = .038; Hedge's g(av) = 0.29) and isometric handgrip strength (7.8%; p = .021; g(av) = 0.59) were significantly superior with beetroot juice ingestion compared to the placebo. In contrast, nonsignificant differences were evident between conditions for all other neuromuscular performance variables (p > .05; g(av )= 0.00-0.27). Red urine production was the only side effect, demonstrating a significantly higher prevalence (p = .046) with beetroot juice ingestion. Three days of beetroot juice supplementation may be a useful nutritional strategy in semi-professional, male handball players given its ergogenic benefit to some aspects of neuromuscular performance.