How much water to drink daily and after training

Water is not a minor detail: it moves nutrients, lubricates your joints and helps you perform and recover. If you train, you sweat; and if you live in Puerto Rico, you sweat more. Here is how much water to drink, with numbers that are easy to follow.

Short answer: aim for about 8 glasses (2 to 3 liters) a day as a base, drink before, during and after training, and weigh yourself before and after: for every pound you lost sweating, drink about 20 to 24 ounces over the next hours. Check the color of your urine: light, you are doing fine; dark, you need more water.

How much water should I drink a day?

A practical guide is to aim for 2 to 3 liters (about 8 to 12 glasses) of fluid a day between what you drink and what your meals provide. The U.S. National Academies reference about 3.7 liters of total water a day for men and 2.7 liters for women (from everything you eat and drink). You need more when it is hot, when you sweat a lot or when you train hard.

You do not have to count to the milliliter. Keep a bottle handy, drink at every meal and do not wait until you are very thirsty: thirst already means you are behind.

How much water should I drink when training?

• Before: arrive hydrated. Drink through the day and a glass or two in the hours before training.
• During: take sips every 15 or 20 minutes, without waiting to be very thirsty.
• After: replace what you sweated out (see the weigh-in trick below).

The weigh-in trick: how much water after training?

It is the easiest way to know how much fluid you lost:

1. Weigh yourself before training (ideally with little clothing).
2. Weigh yourself after, wiping off the sweat.
3. The difference is almost all water you sweated out. For every pound you lost, drink about 20 to 24 ounces of fluid over the next hours.

Example: if you dropped 2 pounds, replace about 40 to 48 ounces (a bit over a liter) over the next hours, not all at once.

How do I know if I am well hydrated?

Check the color of your urine: light, like pale lemonade, you are doing fine. Dark, like apple juice, you need more water. It is the simplest sign and it does not fail.

Do I need drinks with electrolytes?

For most sessions, water is enough. Electrolytes (sodium, potassium) help when:

• You train for more than an hour straight, especially in the heat.
• You sweat a lot or you see white salt on your clothes.

In those cases, a drink with electrolytes or a meal with some salt replaces what you lost. You do not need extra sugar: many sports drinks carry plenty.

Can I drink too much water?

Yes, although it is rare. Drinking huge amounts in a short time can drop your body's sodium too low (hyponatremia), which is dangerous. Do not force liters all at once: spread your water through the day and replace based on what you sweated out.

Training in the island's heat and humidity? See how to train safely in Puerto Rico's heat. And if you want to start moving, try the 20-minute no-equipment home workout.

Sources

• National Academies of Sciences, Engineering, and Medicine (2005). Dietary Reference Intakes for Water, Potassium, Sodium, Chloride, and Sulfate. The National Academies Press. nationalacademies.org
• Sawka M. N. et al. (2007). American College of Sports Medicine position stand: Exercise and fluid replacement. Medicine & Science in Sports & Exercise, 39(2):377-390. doi.org/10.1249/mss.0b013e31802ca597
• Centers for Disease Control and Prevention (CDC). Water and Healthier Drinks. cdc.gov