LESSON 3 · What Your Body Actually Needs
Water and Performance
During intense exercise, athletes can lose 1 to 2 liters of sweat per hour. That sweat is not just water — it carries electrolytes like sodium, potassium, chloride, and magnesium out of your body.

This is why sports drinks exist — though most pack in far more sugar than your body needs. A simpler, cheaper fix is plain water with a pinch of salt and a squeeze of citrus, which puts back the sodium you sweated out without the sugar hit.