Study note • PMID 32708555
Caffeine Supplementation for 4 Days Does Not Induce Tolerance to the Ergogenic Effects Promoted by Acute Intake on Physiological, Metabolic, and Performance Parameters of Cyclists: A Randomized, Double-Blind, Crossover, Placebo-Controlled Study.
Worth trying if it fits your goal and context.
ELI5
In plain language
The present study investigated whether the caffeine supplementation for four days would induce tolerance to the ergogenic effects promoted by acute intake on physiological, metabolic, and performance parameters of cyclists. (randomized trial; trained cyclists).
The abstract suggests a positive effect on 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: The present study investigated whether the caffeine supplementation for four days would induce tolerance to the ergogenic effects promoted by acute intake on physiological, metabolic, and performance parameters of cyclists.
- • The abstract suggests a positive effect on Time-trial performance under the tested conditions.
- • Population: trained cyclists.
- • Protocol cues (title/abstract): 6 mg • 4 Days • 4 days • 60 min • 10 min • 16 km.
Protocol
Protocol (as reported)
- • Intervention/exposure: caffeine (vs placebo).
- • Dose/time/duration cues in abstract/title: 6 mg • 4 Days • 4 days • 60 min • 10 min • 16 km.
- • 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 cyclists) 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 (double-blind, placebo-controlled).
- • Population: trained cyclists.
- • Comparator: placebo.
- • Outcomes measured: Time-trial performance, Time to exhaustion.
- • Protocol cues mentioned: 6 mg • 4 Days • 4 days • 60 min • 10 min • 16 km.
- • Source: PubMed PMID 32708555 (2020) — Nutrients.
Results excerpt
What the abstract reports
“CC and PC showed improvements in time (3.54%, ES = 0.72; 2.53%, ES = 0.51) and in output power (2.85%, ES = 0.25; 2.53%, ES = 0.20) (p < 0.05) compared to CP and PP conditions, respectively.”
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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