Study note • PMID 25729305
Effects of oral sodium supplementation on indices of thermoregulation in trained, endurance athletes.
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: athlete/trained context.
- • Consistency: single-study evidence.
- • Practical recommendation depends on tolerance, context, and whether it protects training consistency.
ELI5
In plain language
Guidelines recommend the consumption of sodium during exercise to replace losses in sweat; however, the effects of sodium on thermoregulation are less clear. (expert consensus / guideline; trained athletes).
In this expert consensus / guideline, the abstract doesn’t find a clear benefit for Time to exhaustion, Performance in heat. Treat this as a signal, not a guarantee; confirm methods and context in the full paper.
Takeaways
What the abstract suggests
- • Study question: Guidelines recommend the consumption of sodium during exercise to replace losses in sweat; however, the effects of sodium on thermoregulation are less clear.
- • In this expert consensus / guideline, the abstract doesn’t find a clear benefit for Time to exhaustion, Performance in heat.
- • Population: trained athletes.
- • Protocol cues (title/abstract): 1800 mg • 3.88 minutes • 3.61 minutes.
Protocol
Protocol (as reported)
- • Intervention/exposure: hydration, fluid.
- • Dose/time/duration cues in abstract/title: 1800 mg • 3.88 minutes • 3.61 minutes.
- • 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 (trained athletes) 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 (double-blind, placebo-controlled).
- • Population: trained athletes.
- • Outcomes measured: Time to exhaustion, Performance in heat, Cramp risk.
- • Protocol cues mentioned: 1800 mg • 3.88 minutes • 3.61 minutes.
- • Source: PubMed PMID 25729305 (2015) — Journal of sports science & medicine.
Results excerpt
What the abstract reports
“Sweat rate was 1015.53 +/- 239.10 ml.hr(-1) during the SS trial and 1053.60+/-278.24 ml/hr during the PL trial, with no difference between trials (p = 0.459).”
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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