How Much Water Should You Drink?

How much water or other fluid you need before, during and after exercise largely depends upon the intensity and duration of exercise. But other factors, such as the air temperature, humidity, altitude and even your own physiology can affect how much water you need during exercise.

Although it can be a difficult to determine exactly how much water individuals need to drink each day, the following recommendations will provide a good starting point for most athletes.

How Much Water Should You Drink Each Day?

If you are training regularly, you will probably need between one half and one whole ounce of water (or other fluids) for each pound of body weight per day.

To determine your baseline range for water requirement, use the following formula:

Low end of range= Body weight (lbs) x 0.5 = (ounces of fluid/day)
High end of range=Body weight (lbs) x 1 = (ounces of fluid/day)

For example, if you weigh 150 pounds, your approximate water requirement will be between 75 and 150 ounces each day.

When to Drink Water During Exercise

Begin the day with a large glass of water each morning, whether it's a training or a rest day. On training days, the following schedule works well for most athletes:

Water (Fluid) Intake Schedule
1. Before Exercise
   • Drink two to three cups of water within the two hours before your workout.
   • Weigh yourself immediately before you begin your workout.
2. During Exercise
   • Drink one cup of water every 15 minutes.
3. After Exercise
   • Weigh yourself immediately after you finish your workout.
   • Drink two to three Cups of water for each pound lost during exercise.

How Much Water to Drink During Endurance Exercise

If you are exercising at a moderate to high intensity for more than 90 minutes, you will want to consume more than plain water. You need to replenish glycogen stores with easy-to-digest carbohydrate. Sports drinks can be an easy way to add the necessary energy. For longer workouts, choose a drink with 60 to 100 calories per eight ounces and consume eight to ten ounces every 15 to 30 minutes based upon your preference.

For those exercising in extreme conditions over three, four or five hours, you'll need to replace electrolytes. A complex sports drink, NUUN tablets, or other foods will help provide the needed calories and electrolytes required for continuous performance.