Calculation & Generation Results
About This Tool
Calculate hourly sweat fluid loss rate (L/hr), total sodium electrolyte depletion (mg Na+ / hr), and hypotonic sports drink electrolyte replenishment for marathoners and triathletes.
Frequently Asked Questions
Why is sodium the most critical electrolyte lost in sweat?
Sodium accounts for over 90% of the electrolyte minerals lost in human perspiration (typically 800 to 1,500 mg per liter of sweat). Potassium, magnesium, and calcium are lost in negligible amounts (<5%).
What is Exercise-Associated Hyponatremia (EAH)?
EAH occurs when an endurance athlete drinks excessive plain water without adequate sodium replacement, diluting blood serum sodium below 135 mEq/L, causing brain swelling (cerebral edema), seizures, and death.
What does a 2% dehydration threshold mean for athletic performance?
Losing more than 2.0% of your body weight in fluid reduces cardiac stroke volume, elevates core body temperature, spikes heart rate, and degrades aerobic endurance output by 10% to 15%.
How do you know if you are a 'salty sweater'?
Salty sweaters develop visible white salt crust on their face, hat, and shirt after running, experience burning eyes from stinging sweat, and taste noticeably salty perspiration.