How much should I drink during a run?

Drink to thirst for runs under 1 hour in moderate conditions. For longer or hotter runs, aim to replace 75-80% of sweat losses. Drinking too much (hyponatremia) is as dangerous as drinking too little.

Does temperature affect hydration needs?

Yes significantly. At 35 degrees C vs 20 degrees C, sweat rates can increase by 50-100%. Hot humid conditions require much more aggressive hydration strategies.

Does drinking cold water improve performance?

Pre-cooling and drinking cold fluids (5-10 degrees C) modestly improves endurance performance in the heat (roughly 1-3%) by reducing core body temperature and thermal sensation.

Hydration Needs During Running Calculator

Calculate fluid intake needs per hour during running based on sweat rate, temperature, and exercise intensity.

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Frequently Asked Questions

How much should I drink during a run?

Does temperature affect hydration needs?

Does drinking cold water improve performance?