Can caffeine improve your performance? Psychophysiological effects - A systematic review.

Caffeine is a widely used ergogenic aid in society, which has made it a topic of interest due to its various benefits at cognitive, physiological, and sports levels, among others. This review aims to investigate the potential benefits of caffeine supplementation in psychophysiological performance through a structured search in the SportsDiscus/Scopus/MEDLINE and Web of Science databases (October 2022). This review followed the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guideline, and the inclusion criteria were defined based on the PICOS model. Double-blind, randomized/semi-randomized crossover articles comparing caffeine intake with an identical placebo condition were included. Filters by age or gender of the participants were not applied. The initial search gave a result of 201 articles, which after eliminating duplicates and applying the inclusion and exclusion criteria, the final sample for this review was 8 studies. The review concluded that 3 (37.5 %) found favorable ergogenic effects, 4 (50 %) found partial effects, and 1 (12.5 %) found no effects of caffeine supplementation on variables related to psychophysiological performance. In general, both partial and negative results could be linked to insufficient doses to produce any change, likewise, habitual caffeine consumption is also a variable that could be attenuating its potential ergogenic effect. In conclusion, moderate doses of caffeine 3-6 mg/kg seem to be an effective strategy to improve the psychophysiological response in various contexts without generating detrimental effects on performance, as long as the intervention designs consider the variables that could condition its effect.