Study note • PMID 23731903
Sodium supplementation has no effect on endurance performance during a cycling time-trial in cool conditions: a randomised cross-over trial.
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: randomized trial.
- • 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
BACKGROUND: Sodium ingestion during exercise may exert beneficial effects on endurance performance by either its ability to attenuate the decrease in plasma volume or reduce the risk of Exercise… (randomized trial; well-trained cyclists).
The abstract reports an association involving Time to exhaustion, Performance in heat, Cramp risk (not necessarily causation). Treat this as a signal, not a guarantee; confirm methods and context in the full paper.
Takeaways
What the abstract suggests
- • Study question: BACKGROUND: Sodium ingestion during exercise may exert beneficial effects on endurance performance by either its ability to attenuate the decrease in plasma volume or reduce the risk of Exercise…
- • The abstract reports an association involving Time to exhaustion, Performance in heat, Cramp risk (not necessarily causation).
- • Population: well-trained cyclists.
- • Protocol cues (title/abstract): 700 mg • 40 min • 171 min • 172 min • 3 h • 72 km.
Protocol
Protocol (as reported)
- • Intervention/exposure: hydration, sodium (vs placebo).
- • Dose/time/duration cues in abstract/title: 700 mg • 40 min • 171 min • 172 min • 3 h • 72 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 (well-trained 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: randomized trial (double-blind, placebo-controlled).
- • Population: well-trained cyclists.
- • Comparator: placebo.
- • Outcomes measured: Time to exhaustion, Performance in heat, Cramp risk.
- • Protocol cues mentioned: 700 mg • 40 min • 171 min • 172 min • 3 h • 72 km.
- • Source: PubMed PMID 23731903 (2013) — Journal of the International Society of Sports Nutrition.
Results excerpt
What the abstract reports
“Sodium supplements had no effect on time-trial performance (overall time = 171 min sodium vs.”
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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