Water intake, high activity
Your activity level changes how much water you need. This page covers a person who weighs 163 lb with 90 minutes of exercise.
How it works
Start with 35 milliliters for each kilogram you weigh. Add 350 milliliters for every 30 minutes you exercise. Divide milliliters by 29.5735 to get fluid ounces. On this page 163 lb with 90 minutes of exercise gives a weight term of 73.94 × 35 = 2587.9 ml.
Worked example
Say a person weighs 163 lb with 90 minutes of exercise. That is 73.94 kg. The body weight part is 73.94 × 35 = 2587.9 ml. Exercise adds 350 × 90 divided by 30 = 1050 ml. Together that is 3637.9 ml, which is 3.64 liters or 123.0 ounces. In cups that is 15.4.
Common questions
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 90 minutes of exercise, spread over 16 waking hours, 3.64 liters is about 227 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 90 minutes of exercise, 3637.9 ml is 123.0 ounces or 15.4 cups.
Do coffee and tea count toward my water?
Most drinks count toward your fluid total, though plain water is the simplest choice. At 163 lb with 90 minutes of exercise, 3.64 liters a day is about 15 cups spread across the day.
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 90 minutes of exercise, treat 3.64 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 90 minutes the page adds 1050 ml. An extra 30 minutes would bring the total to 3987.9 ml.