Effects of Caffeine Intake on 20-30 Year Old Athletes Reaction Time According to the Stroop Test: A Critically Appraised Topic

Authors

  • Carlos Vallejo
  • Kayli Murphy
  • Dr. Matthew O'Brien

Abstract

Clinical Scenario: Caffeine is the most commonly used ergogenic substance in the world. Athletes are frequently identified as a population with high utilization rates, but their use has been a topic of ongoing controversy, particularly in regards to the permissible limits set by athletics governing bodies. Reaction time is a large part of cognitive performance that is incorporated into sports. While caffeine has been found to improve different aspects of athletic performance, it could also have some effects on reaction time in team-sport athletes. Focused Clinical Question: In team-sport athletes ranging from 20 to 30 years of age, does caffeine consumption decrease reaction time according to the Stroop test? Summary of Findings: Patients were given a low to moderate (5mg/kg-1 to 6mg/kg-1) dosage of caffeine prior to exercise protocols. The Stroop test was then utilized to measure their reaction time compared to a placebo sugar pill or solution. After the Stroop test results were evaluated, it was found that males had a small, insignificant decrease in reaction time performance on two of the three tests. The females did not have any remarkable findings in terms of reaction time. Clinical Bottom Line: There were no significant effects on reaction time from caffeine consumption in male or female team-sport athletes compared to a placebo. Athletic trainers can utilize this information to educate coaches, athletes, and other AT’s on making decisions to implement caffeine into their pre-activity routines or rehabilitation plans. Strength of Recommendation: Based on the Oxford Center for Evidence-Based Medicine, the CEBM level of recommendations of these articles were 1b (Almeida RF, et al.) and 2 (Ali A, et al.). 

Keywords: Caffeine AND reaction time AND team sport AND athlete AND placebo

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Published

2026-05-14

Issue

Vol. 10 No. 1 (2026): Articles

Section

Athletic Training

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