Study note • PMID 33077119
Low caffeine dose improves intermittent sprint performance in hot and humid environments.
Worth trying if it fits your goal and context.
ELI5
In plain language
While the effects of caffeine have been evaluated in relation to endurance exercise, few studies have assessed the ergogenic effects of low caffeine doses on intermittent exercise performance in… (randomized trial; participants).
The abstract doesn’t indicate a clear change in Time-trial performance, Performance in heat 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: While the effects of caffeine have been evaluated in relation to endurance exercise, few studies have assessed the ergogenic effects of low caffeine doses on intermittent exercise performance in…
- • The abstract doesn’t indicate a clear change in Time-trial performance, Performance in heat under the tested conditions.
- • Population: participants.
- • Protocol cues (title/abstract): 3 mg • 60 min.
Protocol
Protocol (as reported)
- • Intervention/exposure: caffeine (vs placebo).
- • Dose/time/duration cues in abstract/title: 3 mg • 60 min.
- • Outcomes: Time-trial performance, Time to exhaustion, Performance in heat.
- • 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 (participants) working on supplements.
- • Athletes who can measure Time-trial performance, Time to exhaustion, Performance in heat 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: participants.
- • Comparator: placebo.
- • Outcomes measured: Time-trial performance, Time to exhaustion, Performance in heat.
- • Protocol cues mentioned: 3 mg • 60 min.
- • Source: PubMed PMID 33077119 (2020) — Journal of thermal biology.
Results excerpt
What the abstract reports
“A significant improvement in the total amount of work was observed in the caffeine condition compared to the placebo condition (155.0 +/- 15.8 vs 150.8 +/- 14.5 kJ, respectively; p < 0.05, d = 0.28).”
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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