Effects of Caffeine Mouth Rinse on Cognitive Performance and Psychological Responses in Trained Individuals: A Systematic Review
4 affiliations
- 1Master Program of Sport Facility Management and Health Promotion, National Taiwan University, Taipei 10617, Taiwan
- 2Department of Sport Psychology, Faculty of Sport Science, Universität Leipzig, 04109 Leipzig, Germany
- 3NTU Plus Academy, National Taiwan University, Taipei 106319, Taiwan
- 4Center for Cognitive Interaction Technology (CITEC), Bielefeld University, 33619 Bielefeld, Germany
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.
Related
- Cognitive Performance and Psychological Characteristics in Patients With Clinically Isolated Syndrome: A Case–Control Study
- The Effects of Combined Caffeine and Sodium Bicarbonate Supplementation on Exercise Performance, Physiological Responses, and Gastrointestinal Tolerability: A Systematic Review and Meta-Analysis
- Effects of cognitive behavioral therapy on psychological and physical outcomes in adults with rheumatoid arthritis: a systematic review and meta-analysis of randomized controlled trials
- Effects of brain endurance training on cognitive function, physical performance and perceived exertion in healthy adults: a systematic review and three-level meta-analysis.
- Effects of Occupational Therapy Interventions on Occupational Performance and Physical and Cognitive Fatigue in Adults with Multiple Sclerosis: A Systematic Review of Randomized Controlled Trials
BibTeX
@article{lu2026effects,
title = {{Effects of Caffeine Mouth Rinse on Cognitive Performance and Psychological Responses in Trained Individuals: A Systematic Review}},
author = {Chieh-Ju Lu and Chi-Lun Tsai and Kuo-Pin Wang},
journal = {Nutrients},
year = {2026},
month = nov,
doi = {10.3390/nu18213695},
url = {https://www.mdpi.com/2072-6643/18/21/3695},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - Effects of Caffeine Mouth Rinse on Cognitive Performance and Psychological Responses in Trained Individuals: A Systematic Review
AU - Chieh-Ju Lu
AU - Chi-Lun Tsai
AU - Kuo-Pin Wang
PY - 2026
DA - 2026/11/07
JO - Nutrients
DO - 10.3390/nu18213695
UR - https://www.mdpi.com/2072-6643/18/21/3695
AB - 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.
SN - 2072-6643
ER -