Training Hydration Calculator

Your daily water target based on body weight and training intensity. Two protocols, one number

60 min
Your daily target
— oz
Daily baseline —
Training addition —

The science

ACSM baseline protocol

Your body weight in pounds, divided by two, equals your daily baseline in fluid ounces. This accounts for metabolic water needs at rest. A 170 lb person needs roughly 85 oz (2.5L) before any exercise

American College of Sports Medicine — Exercise and Fluid Replacement Position Stand

Galpin Equation (training)

Body weight in pounds divided by 30 equals ounces needed every 20 minutes during exercise. A 170 lb person needs ~5.7 oz every 20 minutes. This is Dr. Andy Galpin's protocol for training hydration, widely used by elite athletes

Dr. Andy Galpin — Huberman Lab Podcast, Guest Series on Exercise Physiology

Intensity multiplier

Sweat rate varies with intensity. Easy sessions (zone 1-2) use 75% of the Galpin baseline. Hard sessions (zone 4-5, HYROX race pace, heavy lifting) use 125%. The calculator adjusts accordingly

HYDROX does all of this automatically. Free on iOS

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