Start here
- • Food and sleep first — then the few evidence-backed supplements (e.g., caffeine) with a protocol.
- • Avoid anything banned/unsafe; this lab excludes red-line topics.
- • Test in training, never first on race day.
Topic guides
Practical starting points to test conservatively.
Related outcomes
Study library (reference)
Individual studies for deeper reading.
Effects of Caffeine Intake on Endurance Running Performance and Time to Exhaustion: A Systematic Review and Meta-Analysis.
Human research · 2022 · Nutrients · PubMed 36615805
Ergogenic effects of supplement combinations on endurance performance: a systematic review and meta-analysis of randomized controlled trials.
Human research · 2025 · Journal of the International Society of Sports Nutrition · PubMed 40619880
Effect of Pre-Exercise Caffeine Intake on Endurance Performance and Core Temperature Regulation During Exercise in the Heat: A Systematic Review with Meta-Analysis.
Human research · 2022 · Sports medicine (Auckland, N.Z.) · PubMed 35616851
Effects of caffeine chewing gum supplementation on exercise performance: A systematic review and meta-analysis.
Human research · 2023 · European journal of sport science · PubMed 35239468
Effects of caffeine supplementation on muscle endurance, maximum strength, and perceived exertion in adults submitted to strength training: a systematic review and meta-analyses.
Human research · 2021 · Critical reviews in food science and nutrition · PubMed 32551869
Caffeine and Bicarbonate for Speed. A Meta-Analysis of Legal Supplements Potential for Improving Intense Endurance Exercise Performance.
Population not classified in the source record · 2017 · Frontiers in physiology · PubMed 28536531
Acute Effects of Caffeine Supplementation on Physical Performance, Physiological Responses, Perceived Exertion, and Technical-Tactical Skills in Combat Sports: A Systematic Review and Meta-Analysis.
Population not classified in the source record · 2022 · Nutrients · PubMed 35889953
Nutritional Ergogenic Aids in Cycling: A Systematic Review.
Human research · 2024 · Nutrients · PubMed 38892701
Caffeine Placebo Effect in Sport and Exercise: A Systematic Review.
Human research · 2024 · Nutrients · PubMed 39339818
Effect of caffeine ingestion on time trial performance in cyclists: a systematic review and meta-analysis.
Human research · 2024 · Journal of the International Society of Sports Nutrition · PubMed 38836626
Effects of taurine combined with caffeine on repetitive sprint exercise performance and cognition in a hypoxic environment.
Human research · 2025 · Scientific reports · PubMed 39948152
Performance-enhancing effects of caffeine and L-Theanine among Iranian elite wrestlers: a focus on cognitive and specific physical performance.
Human research · 2025 · Journal of the International Society of Sports Nutrition · PubMed 40977612
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Sources
- Effects of Caffeine Intake on Endurance Running Performance and Time to Exhaustion: A Systematic Review and Meta-Analysis.
- Ergogenic effects of supplement combinations on endurance performance: a systematic review and meta-analysis of randomized controlled trials.
- Effect of Pre-Exercise Caffeine Intake on Endurance Performance and Core Temperature Regulation During Exercise in the Heat: A Systematic Review with Meta-Analysis.
- Effects of caffeine chewing gum supplementation on exercise performance: A systematic review and meta-analysis.
- Effects of caffeine supplementation on muscle endurance, maximum strength, and perceived exertion in adults submitted to strength training: a systematic review and meta-analyses.
- Caffeine and Bicarbonate for Speed. A Meta-Analysis of Legal Supplements Potential for Improving Intense Endurance Exercise Performance.
- Acute Effects of Caffeine Supplementation on Physical Performance, Physiological Responses, Perceived Exertion, and Technical-Tactical Skills in Combat Sports: A Systematic Review and Meta-Analysis.
- Nutritional Ergogenic Aids in Cycling: A Systematic Review.