Dietary Nitrate Does Not Improve Neuromuscular Performance And Match-play Demands In Elite Female Hockey Players.

Abstract

PURPOSE: Beetroot juice is a commonly used ergogenic aid that contains high levels of inorganic nitrate (NO3-) and that its intake has proven effectivity at increasing blood nitric oxide (NO) concentrations. The ingestion of beetroot juice has shown good evidence of benefits in endurance sports while team sports has been barely studied. In our knowledge, only a few studies have been developed in team sports athletes. The present study was designed to compare the acute effects of beetroot juice supplementation on physical performance and match-play demands in elite female field hockey players METHODS: Eleven well-trained female hockey players (22.78 ± 5.12 years) participated during the preparatory period of their hockey season in this study. Participants were randomly divided into two groups undergoing a neuromuscular test battery with ingestion of 70 mL beetroot juice (6.4 mmol NO3-) or 70 mL placebo (0.04 mmol NO3-) in two separated days with one week between protocols. A neuromuscular test battery consisted in different test such as; countermovement jump (CMJ), isometric handgrip strength (IHS), and repeated sprint ability test (RSA) were realized. Afterwards a simulated hockey match play (2 x 20 minutes) was realized and the data was recorded by Global Positioning System (GPS). RESULTS: No significant improvements were observed in any physical parameters analysed comparing beetroot juice versus placebo ingestion, CMJ (p = 0.776), IHS (p = 0.829), RSA (p = 0.466). Therefore, no differences were reported in any physical match demands measured by GPS (i.e., total distance covered, number of accelerations/decelerations, etc) (p = 0.063-0.941) CONCLUSIONS: Beetroot juice acute supplementation did not produce any statistically significant improvement in physical performance or match-play demands in elite female field hockey players