Effects of Acute Ecklonia cava Supplementation on Submaximal Cycling and Repeated-Sprint Performance in Trained Cyclists: A Randomised Double-Blind Placebo-Controlled Crossover Trial

Background/Objectives: This study examined whether acute Ecklonia cava (EC) ingestion altered physiological responses during submaximal cycling or power output during subsequent repeated maximal sprints in experienced male cyclists.

Methods

Twelve cyclists completed a randomised, double-blind, placebo-controlled crossover trial. Participants ingested 263 mg of EC extract or placebo 30 min before 60 min of cycling at 55% of the maximum work rate, followed by three 20 s maximal sprints. Blood glucose, blood lactate, heart rate, oxygen uptake and respiratory exchange ratio (RER) were measured during submaximal cycling; peak power, mean power, blood glucose and blood lactate were assessed during the repeated-sprint test. Outcomes were analysed using linear mixed-effects models incorporating treatment, time, treatment × time, experimental period and allocated sequence.