{
  "abstract": "Background: Caffeine mouth rinse (Caf-MR) has been investigated as a non-ingestive strategy that may influence cognitive performance and psychological responses. However, evidence in trained individuals remains limited, and psychological responses have not been comprehensively synthesized. This systematic review evaluated the effects of Caf-MR on cognitive performance and psychological responses in trained individuals. Methods: Six electronic databases were searched through 24 September 2026 for randomized controlled studies comparing Caf-MR with a non-caffeinated placebo or control. Reference lists of relevant reviews and eligible studies were also screened. Owing to heterogeneity in protocols and outcomes, findings were synthesized qualitatively. Results: Ten studies were included; five assessed cognitive outcomes and six psychological responses, with one study contributing to both domains. Cognitive findings were heterogeneous, with improvements observed in selected reaction-time measures and Stroop interference time, as well as fewer errors during a sport-specific cognitive–motor task, while other reaction-time and accuracy outcomes showed no clear benefit. Among psychological studies, only one reported a Caf-MR-specific increase in felt arousal, with no consistent effects on mood, motivation, mental effort, mental fatigue, or enjoyment. Methodological quality ranged from fair to good, and all studies had some concerns regarding overall risk of bias. Conclusions: Overall, despite improvements in selected cognitive outcomes, current evidence remains insufficient to establish consistent cognitive or psychological benefits of Caf-MR in trained individuals. Future research should prioritize assessing blinding effectiveness, comparing Caf-MR protocols under standardized experimental conditions, and using comparable outcome measures to clarify potential differences across tasks and contexts.",
  "abstract_shown": true,
  "affiliations": [
    "Master Program of Sport Facility Management and Health Promotion, National Taiwan University, Taipei 10617, Taiwan",
    "Department of Sport Psychology, Faculty of Sport Science, Universität Leipzig, 04109 Leipzig, Germany",
    "NTU Plus Academy, National Taiwan University, Taipei 106319, Taiwan",
    "Center for Cognitive Interaction Technology (CITEC), Bielefeld University, 33619 Bielefeld, Germany"
  ],
  "article_type": null,
  "arxiv": null,
  "author_total": 3,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Chieh-Ju Lu",
      "orcid": "0009-0007-7939-2615"
    },
    {
      "affs": [
        1
      ],
      "name": "Chi-Lun Tsai",
      "orcid": "0000-0002-1882-6738"
    },
    {
      "affs": [
        0,
        2,
        3
      ],
      "name": "Kuo-Pin Wang",
      "orcid": "0000-0001-8097-7927"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/b3jz8maazzdsf.bib",
  "cited_by": 0,
  "doi": "10.3390/nu18213695",
  "fulltext_url": null,
  "id": "b3jz8maazzdsf",
  "issns": [
    "2072-6643"
  ],
  "landing_url": "https://www.mdpi.com/2072-6643/18/21/3695",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [],
  "openalex": null,
  "pdf_url": null,
  "pmcid": null,
  "pmid": null,
  "published": "2026-11-07",
  "publisher": "MDPI AG",
  "ris": "https://research.draconitic.com/paper/b3jz8maazzdsf.ris",
  "sources": [
    {
      "first_seen": "2026-11-10T00:21:40Z",
      "native_id": "10.3390/nu18213695",
      "source": "crossref",
      "url": "https://www.mdpi.com/2072-6643/18/21/3695"
    }
  ],
  "subjects": [
    {
      "field": "medicine",
      "origin": "issn:2072-6643",
      "subfield": "nutrition"
    }
  ],
  "title": "Effects of Caffeine Mouth Rinse on Cognitive Performance and Psychological Responses in Trained Individuals: A Systematic Review",
  "title_text": "Effects of Caffeine Mouth Rinse on Cognitive Performance and Psychological Responses in Trained Individuals: A Systematic Review",
  "type": "peer-reviewed",
  "updated_at": "2026-11-10T00:21:40Z",
  "url": "https://research.draconitic.com/paper/b3jz8maazzdsf",
  "venue": "Nutrients",
  "versions": []
}