Study note • PMID 34010807
Habitual Caffeine Consumption Does Not Interfere With the Acute Caffeine Supplementation Effects on Strength Endurance and Jumping Performance in Trained Individuals.
Worth trying if it fits your goal and context.
ELI5
In plain language
The long-standing caffeine habituation paradigm was never investigated in strength endurance and jumping exercise performance through a straightforward methodology. (randomized trial; trained participants).
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: The long-standing caffeine habituation paradigm was never investigated in strength endurance and jumping exercise performance through a straightforward methodology.
- • The abstract doesn’t indicate a clear change in Time-trial performance under the tested conditions.
- • Population: trained participants.
- • Protocol cues (title/abstract): 11 mg/day • 33 mg/day • 167 mg/day • 6 mg/kg.
Protocol
Protocol (as reported)
- • Intervention/exposure: caffeine (vs placebo).
- • Dose/time/duration cues in abstract/title: 11 mg/day • 33 mg/day • 167 mg/day • 6 mg/kg.
- • 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 participants) 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 participants.
- • Comparator: placebo.
- • Outcomes measured: Time-trial performance, Time to exhaustion.
- • Protocol cues mentioned: 11 mg/day • 33 mg/day • 167 mg/day • 6 mg/kg.
- • Source: PubMed PMID 34010807 (2021) — International journal of sport nutrition and exercise metabolism.
Results excerpt
What the abstract reports
“Caffeine side effects were similar in low, moderate, and high caffeine consumers.”
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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