There is no universally applicable liter amount. The European authority EFSA cites 2.5 liters per day for men and 2.0 liters for women as a guideline. Important: this is total water — beverages plus water from food. Approximately 20 to 30 percent comes from food. As a beverage amount, roughly 1.5 to 2.0 liters remain.
This guideline applies to temperate climates and moderate activity. It is derived from observed drinking amounts, not from a measured requirement — a guideline, not a mandate.
During training, sweat loss is added, and it varies greatly from person to person. That is why self-measurement is more meaningful than any table: weigh body weight before and after the session. A kilogram of loss corresponds to approximately one liter of fluid.