Acute Effects of Guarana (Paullinia cupana) Supplementation on Cognitive Performance, Technical Skills, and Physiological Responses in Amateur Soccer Players

This study investigated the acute effects of guarana supplementation on cognitive, technical, physiological, and psychological responses in soccer players prior to, during, and following high-intensity 4 vs. 4 small-sided games (SSGs). Thirty-two male amateur soccer players (20.1 ± 2.9 years) completed a randomized, double-blind, placebo-controlled crossover trial involving guarana (300 mg) and placebo, separated by a 7-day washout. After a 70 min absorption period, participants performed the Trail Making Test (TMT-A/B) and Loughborough Soccer Passing Test (LSPT) before and after a 20 min SSG protocol. Heart rate (HR), HR recovery, perceived physical exertion, perceived mental exertion, mood state, and 24 h wellness were assessed. Guarana significantly improved TMT-A performance compared with placebo (p = 0.005, η2p = 0.05), whereas no significant differences were observed for TMT-B (p = 0.08, η2p = 0.02). A significant Group × Time interaction was found for total LSPT performance time (p = 0.01, η2p = 0.06), driven by a significant technical performance optimization at pre-exercise (p < 0.01) that dissipated post-exercise (p > 0.05). Guarana significantly increased mean exercise HR (p < 0.05) and slowed early recovery kinetics (p < 0.05) without altering perceived physical exertion (p > 0.05). Concurrently, it significantly reduced perceived mental exertion (p < 0.01) and attenuated Total Mood Disturbance (p < 0.001). No significant between condition variations were noted for 24 h wellness indices (p > 0.05). These findings suggest that acute low-dose guarana administration may improve basic attentional readiness and was associated with improved pre-exercise technical performance, although this performance advantage was attenuated following high-intensity physical exertion.