Water intake, moderate activity
This page is for a moderate activity routine. The sample person weighs 163 lb with 30 minutes of exercise.
How it works
Multiply your weight in kilograms by 35 to get milliliters of water. Add 350 milliliters for every 30 minutes of exercise. The page converts the total to liters and ounces. For 163 lb with 30 minutes of exercise, the exercise part is 350 ml.
Worked example
Take a person who weighs 163 lb with 30 minutes of exercise. In metric that is 73.94 kg. Multiply by 35: 73.94 × 35 = 2587.9 ml. Exercise adds 350 × 30 divided by 30 = 350 ml. The total is 2937.9 ml. Divide by 1000 to get 2.94 liters. Divide 2937.9 by 29.5735 to get 99.3 ounces. Divide by 8 to get 12.4 cups.
Common questions
Does food count toward the total?
Food contains water. Treat the result as a goal for your total fluid across the day and not a quota for drinks alone. At 163 lb with 30 minutes of exercise, treat 2.94 liters as a goal for the day, not a quota for one sitting.
What if I exercise more or less than this?
Change the exercise minutes. Each 30 minutes adds 350 milliliters. At 30 minutes the page adds 350 ml. An extra 30 minutes would bring the total to 3287.9 ml.
Is 35 milliliters per kilogram right for everyone?
No. It is a common starting estimate. Heat, illness, pregnancy and some health conditions change needs. For 163 lb the starting figure is 2587.9 ml before exercise, and 2937.9 ml with 30 minutes of exercise.
Can I drink too much water?
Yes, though it is uncommon. Drinking far more than you need in a short time can dilute the salts in your blood. Spread your intake through the day. At 163 lb with 30 minutes of exercise, spread over 16 waking hours, 2.94 liters is about 184 ml an hour.
How many ounces or cups is that?
A US fluid ounce is 29.5735 milliliters and a cup is 8 ounces. At 163 lb with 30 minutes of exercise, 2937.9 ml is 99.3 ounces or 12.4 cups.