Effects of Caffeine on Agility in Amateur Soccer Players

This randomized, double-blind, placebo-controlled crossover clinical trial aims to investigate the acute effects of caffeine supplementation on motor and perceptual-cognitive components of agility performance in male amateur soccer players. The main questions are: i) Does acute caffeine supplementation improve motor performance, including countermovement jump height, drop-jump reactive strength, and planned agility? ii) Does acute caffeine supplementation improve perceptual-cognitive performance during reactive agility tasks involving light and human stimuli? Participants will complete two experimental conditions in randomized order, receiving either 300 mg of caffeine (\~3.7 miligrams/kilograms of body mass) or placebo pills. Following ingestion, participants will perform countermovement and drop jumps and three Y-shaped agility tests assessing planned agility, reactive agility to a light stimulus, and reactive agility to a human stimulus.