Effects of Caffeine and Nicotine Gum on Balance Performance in Athletes

This randomized, single-blind, placebo-controlled, four-condition crossover study evaluates the acute effects of caffeine gum (\~3 mg/kg) and nicotine gum (4 mg) on balance performance in healthy, trained adults. Each participant completes four test visits (caffeine gum, nicotine gum, xylitol-based placebo gum, and no-gum control) separated by ≥24 hours. Static and dynamic balance are assessed using the ProKin 252 system under standardized procedures. The primary outcomes are postural sway (ellipse area) and center-of-pressure path length over predefined test trials/time frames. The objective is to determine whether acute administration of these stimulants alters balance-related performance relative to placebo and control.