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Influence of the CYP1A2 genotype on the exercise performance of physically active individuals under caffeine
Gabriel Peres Messenburger1, Fernanda Ferreira Nuñez2, Olavo Porepp3
1College of Nutrition, Federal University of Pelotas, Pelotas, RS, Brazil.
Abstract:
This study aims to evaluate the influence of the CYP1A2 genotype on the exercise performance of athletes and physically active individuals with caffeine supplementation. We followed the recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-Analysis. The search was performed up to May 2025 and included the following databases: PubMed, EMBASE, Scopus, Web of Science, Cochrane Central Register of Controlled Trials, CINAHL, LILACS, and SPORTDiscus. Only randomized clinical trials evaluating the effects of caffeine supplementation and the influence of the CYP1A2 genotype on exercise performance were included. The risk of bias was evaluated using the updated version of the Cochrane tool for assessing bias risk in randomized trials (RoB 2). We included 19 studies, involving 732 participants, and published between 2012 and 2024. Dosages of caffeine supplementation ranged from 2 to 9 mg/kg. Although there is no consensus among all studies, caffeine supplementation has shown positive results in sports performance in individuals with the AA genotype, as well as positive for AC individuals with smaller effect sizes, and null or negative for individuals with the CC genotype. The majority (84%) of the included studies were classified as "some concerns" in our risk of bias analysis, with only two studies classified as having a low risk of bias. Caffeine may enhance athletic performance in various sports modalities and physical tests in individuals with the AA genotype, may also demonstrate marginal improvement in AC individuals, and has null or detrimental effects on individuals with the CC genotype.
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