Study note • PMID 32551869
Effects of caffeine supplementation on muscle endurance, maximum strength, and perceived exertion in adults submitted to strength training: a systematic review and meta-analyses.
Worth trying if it fits your goal and context.
ELI5
In plain language
This study aimed to determine the effects of caffeine supplementation on muscle endurance, maximum strength, and ratings of perceived exertion (RPE) in individuals undergoing strength training with external resistance exercises. (systematic review / meta-analysis; participants).
In this systematic review / meta-analysis, the abstract doesn’t find a clear benefit for Time-trial performance, Time to exhaustion. Treat this as a signal, not a guarantee; confirm methods and context in the full paper.
Takeaways
What the abstract suggests
- • Study question: This study aimed to determine the effects of caffeine supplementation on muscle endurance, maximum strength, and ratings of perceived exertion (RPE) in individuals undergoing strength training with external resistance exercises.
- • In this systematic review / meta-analysis, the abstract doesn’t find a clear benefit for Time-trial performance, Time to exhaustion.
- • Population: participants.
- • Protocol cues: abstract may omit dose/timing; use the full paper to replicate accurately.
Protocol
Protocol (as reported)
- • Intervention/exposure: caffeine.
- • Dose/time/duration: abstract doesn’t include enough detail; use the full paper’s methods section.
- • 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 (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: systematic review / meta-analysis (double-blind, placebo-controlled).
- • Population: participants.
- • Outcomes measured: Time-trial performance, Time to exhaustion.
- • Source: PubMed PMID 32551869 (2021) — Critical reviews in food science and nutrition.
Results excerpt
What the abstract reports
“More investigations are needed to clarify the contradictions in its effects regarding lower-body exercises.”
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).
- • Reviews and consensus statements mix protocols and populations; recommendations may not match your exact constraints.
- • 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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Performance Science Lab
Research-backed protocols and evidence grades for endurance performance — built for athletes.
Supplements performance research
Supplements are optional. Only a few reliably move the needle, and context matters.
Caffeine for endurance performance: a practical protocol
Evidence-informed protocol: Caffeine for endurance performance: a practical protocol. Practical steps, who it helps, and what to watch out for.
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.