Study note • PMID 23573201
The metabolic and performance effects of caffeine compared to coffee during endurance exercise.
Worth trying if it fits your goal and context.
ELI5
In plain language
There is consistent evidence supporting the ergogenic effects of caffeine for endurance based exercise. (randomized trial; trained triathletes).
The abstract doesn’t indicate a clear change in Time-trial performance under the tested conditions. Treat this as a signal, not a guarantee; confirm methods and context in the full paper.
Takeaways
What the abstract suggests
- • Study question: There is consistent evidence supporting the ergogenic effects of caffeine for endurance based exercise.
- • The abstract doesn’t indicate a clear change in Time-trial performance under the tested conditions.
- • Population: trained triathletes.
- • Protocol cues (title/abstract): 5 mg • 5 mg/kg • 30 min • 45 min • 1.22 min • 1 h.
Protocol
Protocol (as reported)
- • Intervention/exposure: caffeine (vs placebo).
- • Dose/time/duration cues in abstract/title: 5 mg • 5 mg/kg • 30 min • 45 min • 1.22 min • 1 h • 55% VO2max • 04 m.
- • Outcomes: Time-trial performance, Time to exhaustion.
- • Replication note: abstracts often omit adherence and timing; confirm details before changing training or supplementation.
Fit
Who it helps, and who should skip it
Who it helps
- • Athletes similar to the study population (trained triathletes) working on supplements.
- • Athletes who can measure Time-trial performance, Time to exhaustion with a repeatable workout or time-trial effort.
Who should skip
- • If you have symptoms or conditions that make the intervention risky, get professional guidance.
- • If you’re near race day and can’t safely test, defer the experiment.
Methods
What the study actually did
- • Design: randomized trial (placebo-controlled).
- • Population: trained triathletes.
- • Comparator: placebo.
- • Outcomes measured: Time-trial performance, Time to exhaustion.
- • Protocol cues mentioned: 5 mg • 5 mg/kg • 30 min • 45 min • 1.22 min • 1 h • 55% VO2max • 04 m.
- • Source: PubMed PMID 23573201 (2013) — PloS one.
Results excerpt
What the abstract reports
“No significant differences were observed between placebo and decaf during the TT.”
Note: excerpts are short; for full context, read the paper.
Limits
Limitations & bias
- • Abstract-only summaries can miss critical details (population, protocol, adherence, and context).
- • Single studies often don’t generalize to your event, history, and training load; treat results as a starting point.
- • If your context differs (elite vs recreational; cycling vs running), adjust expectations and be conservative.
- • This is performance information, not medical advice.
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Time-trial performance research for endurance athletes
Practical performance outcome used in many studies: closer to racing than lab-only metrics.
Time to exhaustion research for endurance athletes
A lab outcome that can still guide training: it often tracks fatigue resistance.