Cortez, LuisMackay, KarenContreras, EdwinPeñailillo, Luis2024-09-242024-09-242017-01RICYDE: Revista Internacional de Ciencias del Deporte Volume 13, Issue 47, Pages 52 - 62January 20171885-3137https://repositorio.unab.cl/handle/ria/60448Indexación: ScopusCaffeine is considered an enhancing aid and most consumed in sports, mainly due to its stimulant properties on the central nervous system, improving athletic performance and decreasing muscle fatigue. Objective: The aim of this study was to investigate the acute effect of caffeine on the reaction time and muscle activity of a Dollyo Chagi kick in taekwondo fighters. Methods: Thirteen taekwondo fighters ingested either 5 mg of caffeine per kg of body mass or a placebo. Reaction time and muscle activity were measured 60 min before the intake of caffeine or placebo, 60 min after ingestion and after a fatigue stimuli. Surface electromyogram (sEMG) amplitude, and time of reaction of the muscles rectus femoris, vastus lateralis, vastus medialis and biceps femoris during a circular kick related to a sound stimulus were measured. Results: Caffeine ingestion decreased the reaction time of the rectus femoris muscle 60-minutes after ingestion of caffeine and after strenuous stimulation (P<0.05). No significant decrease in reaction time was observed in other muscles. Furthermore, no changes in muscles activity in any other muscles were found. Conclusion: Caffeine supplementation in taekwondo athletes could reduce the reaction time of a Dollyo Chagi round kick after 60 minutes of ingestion and after a fatigue stimuli.esCombat sportsErgogenic aidFatigueMuscle activitySupplementationArtículo10.5232/ricyde2017.04704