Study note • PMID 16556786
Core temperature and hydration status during an Ironman triathlon.
Worth trying if it fits your goal and context.
ELI5
In plain language
To measure core temperature (Tcore) in triathletes during a 226 km Ironman triathlon, and to compare Tcore with markers of hydration status after the event. (controlled study; well-trained triathletes).
The abstract doesn’t indicate a clear change in 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: To measure core temperature (Tcore) in triathletes during a 226 km Ironman triathlon, and to compare Tcore with markers of hydration status after the event.
- • The abstract doesn’t indicate a clear change in Performance in heat under the tested conditions.
- • Population: well-trained triathletes.
- • Protocol cues (title/abstract): 226 km.
Protocol
Protocol (as reported)
- • Intervention/exposure: hydration, sodium.
- • Dose/time/duration cues in abstract/title: 226 km.
- • Outcomes: Time to exhaustion, Performance in heat, Cramp risk.
- • 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 (well-trained triathletes) working on hydration.
- • Athletes who can measure Time to exhaustion, Performance in heat, Cramp risk 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: well-trained triathletes.
- • Outcomes measured: Time to exhaustion, Performance in heat, Cramp risk.
- • Protocol cues mentioned: 226 km.
- • Source: PubMed PMID 16556786 (2006) — British journal of sports medicine.
Results excerpt
What the abstract reports
“Mean (SD) performance time in the Ironman triathlon was 611 (49) minutes; heart rate was 143 (9) beats/min (83 (6)% of maximum) and Tcore was 38.1 (0.3) degrees C.”
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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