The effect of caffeine, glucose, and combined caffeine-glucose mouth rinsing on vertical jump performance among male amateur volleyball players

This study investigated whether mouth rinsing with caffeine glucose or a combined solution improves vertical jump performance in male amateur volleyball players. Twelve participants aged eighteen to twenty five completed four randomized testing sessions evaluating placebo six-point four percent glucose one point two percent caffeine and a combined caffeine glucose solution each separated by a forty-eight-hour washout period. Before performing countermovement jumps measured on a Vertec device participants rinsed twenty-five milliliters of the given solution for ten seconds. The overall design allowed researchers to assess if activating oral receptors with carbohydrate and caffeine solutions without swallowing could enhance explosive lower body strength and jumping height.