Research

Mixed

Conservative fluid intake strategies are recommended for ultra-endurance events in moderate conditions to avoid hyponatremia, while oral sodium supplementation assists in maintaining hydration balance.

In moderate weather, do not over-drink. Aim for 500-800 mL/h on the bike and 300-500 mL/h on the run. Include sodium in your fluids to prevent hyponatremia. Smaller athletes should drink less.

ModerateQualifiesMEDIUM confidence
According to Sharwood et al. [41], conservative drinking policy can be advocated for those Ironman triathlons that are held in moderate environmental conditions... Oral sodium supplementation has been shown to assist in maintaining hydration balance during ultra-endurance events [39].
Calvin Zaryski et al. · Current Sports Medicine Reports · 2005

Why this rating

Review article citing specific studies on fluid balance.

Source

Training Principles and Issues for Ultra-endurance Athletes

Calvin Zaryski et al. · Current Sports Medicine Reports · 2005

DOI 10.1097/01.csmr.0000306201.49315.73

narrative_reviewCited 224×
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DOI resolved against Crossref · corpus check 2026-06-10

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