Beetroot Beverage and Repeated Sprint Power Output During RAST
This randomized, double-blind, placebo-controlled crossover trial aims to evaluate the acute effects of a nitrate-rich beetroot-based beverage on repeated sprint performance in trained athletes. Ten athletes will complete two experimental conditions in randomized order: beetroot beverage (BET) and placebo (PLA), separated by a 7-day washout period. The beetroot beverage consists of 200 mL of a mixture containing beetroot, cocoa, and green tea, providing approximately 6.4 mmol of nitrate. In each condition, participants will perform a Running Anaerobic Sprint Test (RAST), consisting of six maximal 35-meter sprints with 10 seconds of passive recovery between sprints. The primary outcome is mean power output across the six sprints. Secondary outcomes include fatigue index, sprint-by-sprint power output, heart rate, rating of perceived exertion (Borg 6-20 scale), maximal oxygen uptake (VO₂max), and sleep quality assessed using the Insomnia Severity Index (ISI).
Healthy trained athletes