How Does Caffeine Enhance Athletic Performance? A Literature Review of Its Effects, Mechanisms of Action, Safety, Side Effects, and Sport- and Sex-Based Differences.

Introduction: Caffeine is a methylxanthine compound naturally found in coffee beans, tea leaves, and cocoa. It is among the most widely consumed psychoactive substances worldwide. Its primary mechanism of action involves antagonism of adenosine receptors within the central nervous system, resulting in reduced perception of fatigue and enhanced alertness. Caffeine’s effects on the peripheral nervous system include increased intracellular calcium release and inhibition of phosphodiesterase activity, thereby enhancing muscle contractility and promoting utilization of energy substrates [1]. The metabolic effects of caffeine encompass multiple biochemical pathways [8]. Although caffeine exerts a multifactorial effect on aerobic performance its use should be carefully considered in the context of potential adverse effects [12]. Evidence derived from studies conducted in diverse athletic populations suggests that caffeine supplementation may represent an effective strategy for optimizing performance while preserving long-term athlete health.Aim of the study :The aim of this study is to systematically analyze available literature regarding the effects of caffeine, its mechanisms of action, safety profile, adverse effects, and variability in response according to sport discipline and sex.Material and Methods: Review and analysis of randomized clinical trials and clinical trials from 2010 to 2025 available on PubMed and Google Scholar.Conclusions: The findings indicate that caffeine may serve as an effective ergogenic aid across a wide range of sports disciplines, provided that it is administered within safe dosage ranges tailored to individual needs—taking into account the specific characteristics of the discipline, athlete-related factors and individual tolerance [2]. Furthermore, current evidence indicates comparable magnitude of benefits in both female and male athletes across various disciplines [5], highlighting the broad applicability of caffeine as an ergogenic aid.