Starting from a simple recalculation, that a healthy person staying under normal conditions loses from 25 to 50 ml of water per hour, it is easy to calculate the recommended capacity by multiplying your own weight in kilograms by about 30 ml for every kilogram of a body. Of course, the demand increases with heatwaves or physical exertion. This means that a person with a weight of 50 kg should drink 1.5 litres of water, and a person with a weight of 100 kg should drink 3.0 litres of water. All this to satisfy the basic needs of your body. Remember, the balance must break even!