We need water to live. All our cells soak in it, though some tissues (such as muscle) have a higher water content than others (such as body fat).

Most adults need around 3 L (about 12 cups) of fluid each day as a baseline. Since 1 L (about 4 cups) comes from our food, this means that 2 L (about 8 cups) comes from drinking.

If you’re exercising hard, you might need up to 6 L (about 24 cups) per day.

You can estimate fluid needs by bodyweight. For every kilogram of bodyweight, ingest 30-40 ml of water.

We lose both water and salts when sweating. But since we lose more water than salts, we risk electrolyte imbalance when exercising hard for a long time. Losing even small amounts of water can affect our athletic performance and energy. Changes include reduced muscular endurance time, reduced muscle strength, reduced endurance time and heat cramps.

Symptoms of dehydration include; headache, fatigue, low blood pressure, dizziness and/or fainting, nausea, flushing, and, rapid heart rate.

Fill up a one-litre bottle of water and keep it near you throughout the day. When you notice it, take a few sips. Your goal is to finish two of these bottles by the end of the day.

For most average people, plain water in moderate amounts is just fine. You don’t need sports drinks or extra-hydration. But if we sweat a lot, we lose enough electrolytes for it to matter. Electrolytes are minerals such as sodium, potassium, chloride, calcium and magnesium. Only then do you need to consider an electrolyte replacer.