Study note • PMID 34074584
Effect of acute caffeine supplementation before intermittent high-intensity exercise on cytokine levels and psychobiological parameters: A randomized, cross-over, placebo-controlled trial.
Worth trying if it fits your goal and context.
ELI5
In plain language
The present study aimed to verify the effects of caffeine supplementation on psychobiological parameters and its relationship with inflammatory cytokines in non-athlete subjects. (randomized trial; athletes).
The abstract reports an association involving Time to exhaustion (not necessarily causation). 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 aimed to verify the effects of caffeine supplementation on psychobiological parameters and its relationship with inflammatory cytokines in non-athlete subjects.
- • The abstract reports an association involving Time to exhaustion (not necessarily causation).
- • Population: athletes.
- • Protocol cues (title/abstract): 6 mg • 1 min • 2 min • 1 h.
Protocol
Protocol (as reported)
- • Intervention/exposure: caffeine (vs placebo).
- • Dose/time/duration cues in abstract/title: 6 mg • 1 min • 2 min • 1 h.
- • 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 (athletes) 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: athletes.
- • Comparator: placebo.
- • Outcomes measured: Time-trial performance, Time to exhaustion.
- • Protocol cues mentioned: 6 mg • 1 min • 2 min • 1 h.
- • Source: PubMed PMID 34074584 (2021) — Cytokine.
Results excerpt
What the abstract reports
“Moreover, 1 h post-PE vigor level was higher in the CAF group versus PLA group (4.53; 95% CI: 1.27 to 7.80; z = 2.72; p = 0.006; d = 0.46), and fatigue was lower in CAF group than PLA group (-5.08; 95% CI:…”
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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