Hydration is a range, not a number
Your kidneys handle wide swings in intake without trouble. The goal is to avoid the extremes: chronic mild dehydration, which shows up as headaches and flat training performance, and overdrinking to the point of diluting sodium.
- • Sessions over 60–90 minutes in heat need electrolytes, not just water.
- • Weigh before and after a long workout — each pound lost is about 16 oz of fluid.
- • Coffee and tea count toward daily fluid despite their mild diuretic effect.
FAQ
How much water should I drink a day?
For most adults, roughly half an ounce per pound of body weight plus replacement for exercise and heat. That lands most people between 2.5 and 4 liters of total fluid including food.
Is 8 glasses a day right?
It is a reasonable baseline for a sedentary average-sized adult but too little for anyone larger, active, or in a hot climate.
Can you drink too much water?
Yes. Consuming several liters in a short window without electrolytes can dilute blood sodium, which is dangerous. Spread intake across the day.
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