Study note • PMID 24444237
Fluid balance of cyclists during a 387-km race.
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: expert consensus / guideline.
- • 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
Current hydration guidelines are designed to address the fine balance between minimising dehydration while reducing the risk of hyponatremia. (expert consensus / guideline; cyclists).
In this expert consensus / guideline, the abstract suggests potential trade-offs that could affect Time to exhaustion, Performance in heat, Cramp risk. Treat this as a signal, not a guarantee; confirm methods and context in the full paper.
Takeaways
What the abstract suggests
- • Study question: Current hydration guidelines are designed to address the fine balance between minimising dehydration while reducing the risk of hyponatremia.
- • In this expert consensus / guideline, the abstract suggests potential trade-offs that could affect Time to exhaustion, Performance in heat, Cramp risk.
- • Population: cyclists.
- • Protocol cues (title/abstract): 387 km.
Protocol
Protocol (as reported)
- • Intervention/exposure: hydration, fluid.
- • Dose/time/duration cues in abstract/title: 387 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 (cyclists) 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: expert consensus / guideline.
- • Population: cyclists.
- • Outcomes measured: Time to exhaustion, Performance in heat, Cramp risk.
- • Protocol cues mentioned: 387 km.
- • Source: PubMed PMID 24444237 (2014) — European journal of sport science.
Results excerpt
What the abstract reports
“Upon completion of the race 7 of the 18 (39%) cyclists had blood sodium concentrations of 135 mmol L(-1) or lower with one cyclist recording a value of 132 mmol L(-1).”
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).
- • 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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