Study note • PMID 24950110
Hydration strategies, weight change and performance in a 161 km ultramarathon.
How to use this page
This note summarizes one study record. Check the participants, methods, results, and limitations before applying it to training.
- • Design signal: controlled study.
- • Population relevance: mixed/unclear athlete specificity.
- • Consistency: single-study evidence.
- • Practical recommendation depends on tolerance, context, and whether it protects training consistency.
ELI5
In plain language
To examine controversies about hydration strategies, participants (383 starters) of a 161 km ultramarathon (maximum temperature 39.0 degrees C) underwent body weight measurements before, during and after the race;… (controlled study; runners).
The abstract doesn’t indicate a clear change in Time to exhaustion, Performance in heat, Cramp risk 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 examine controversies about hydration strategies, participants (383 starters) of a 161 km ultramarathon (maximum temperature 39.0 degrees C) underwent body weight measurements before, during and after the race;…
- • The abstract doesn’t indicate a clear change in Time to exhaustion, Performance in heat, Cramp risk under the tested conditions.
- • Population: runners.
- • Protocol cues (title/abstract): 161 km • 90 km.
Protocol
Protocol (as reported)
- • Intervention/exposure: hydration, sodium.
- • Dose/time/duration cues in abstract/title: 161 km • 90 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 may help, and who should be cautious
Who it helps
- • Athletes similar to the study population (runners) 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 be cautious
- • 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: runners.
- • Outcomes measured: Time to exhaustion, Performance in heat, Cramp risk.
- • Protocol cues mentioned: 161 km • 90 km.
- • Source: PubMed PMID 24950110 (2014) — Research in sports medicine (Print).
Results excerpt
What the abstract reports
“There was no difference in the extent of weight loss (mean 2.0-3.1%) or the weight change pattern when comparing groups using different hydration strategies.”
Note: excerpts are short; for full context, read the paper.
Limits
Limitations and 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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