Study note • PMID 31894415
Rising vs. falling phases of core temperature on endurance exercise capacity in the heat.
Useful, but technique/population sensitive.
ELI5
In plain language
Core temperature (T(c)) shows rising (05:00-17:00 h) and falling (17:00-05:00 h) phases. (controlled study; participants).
Effects on Performance in heat are mixed or unclear from the abstract alone. Treat this as a signal, not a guarantee; confirm methods and context in the full paper.
Takeaways
What the abstract suggests
- • Study question: Core temperature (T(c)) shows rising (05:00-17:00 h) and falling (17:00-05:00 h) phases.
- • Effects on Performance in heat are mixed or unclear from the abstract alone.
- • Population: participants.
- • Protocol cues (title/abstract): 00 h • 16.3 min • 14.6 min.
Protocol
Protocol (as reported)
- • Intervention/exposure: rising, falling.
- • Dose/time/duration cues in abstract/title: 00 h • 16.3 min • 14.6 min.
- • Outcomes: 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 heat.
- • Athletes who can measure 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: controlled study.
- • Population: participants.
- • Outcomes measured: Performance in heat.
- • Protocol cues mentioned: 00 h • 16.3 min • 14.6 min.
- • Source: PubMed PMID 31894415 (2020) — European journal of applied physiology.
Results excerpt
What the abstract reports
“Moreover, perceived fatigue during exercise and thermal perception during and following exercise are lower in the late evening than morning.”
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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