Many of us have grown up hearing the 8 x 8 rule- drink eight 8 oz. glasses per day. However, the U.S. National Academies of Sciences, Engineering, and Medicine determined that our adequate daily intake is much higher. For adult men, the daily intake of fluids should be about 15.5 cups
(3.7 liters) while for women it should be about 11.5 cups (2.7 liters)
For those who are athletes or exercise recreationally, hydration is critical for maximizing the benefits of exercise, maximizing performance, and avoiding dehydration. The American Council on Exercise has set guidelines for how much water should be consumed around a workout
Before your workout, you should drink 18-20 oz of water 2 to 3 hours prior and 8 oz within 30 minutes of your warm-up. After every 10 to 20 minutes of exercise, you should be drinking 8-10 oz of water to help minimize fatigue.
Once you have completed your workout, you should be
drinking 16 to 24 oz per pound of body weight lost during exercise. For those who have completed 60+ minutes of high-intensity exercise, replenishing with water or a sports drink with electrolytes can benefit muscle recovery. 
Thirst is one of the first signs of dehydration. Other symptoms include dark urine, nausea, headache, dizziness, mouth & skin dryness, and irritability. One way you can stay on top of your fluid intake is to grab a water bottle or a journal to record each glass throughout the day. While
it may seem daunting to drink two liters or more per day, what we eat can help reach this goal.
About 20% of the food we eat can contribute to our daily fluid intake. Foods such as watermelon, cantaloupe, strawberries, cucumbers, celery, bell peppers, broths and soups all have water contents above 90%.
1. Thomas DT, et al. Position of the Academy of Nutrition and Dietetics, Dietitians of Canada, and American College of Sports Medicine: Nutrition and athletic performance. Medicine & Science in Sports & Exercise. 2016; doi:10.1016/j.jand.2015.12.006.
2. American Council on Exercise. (2009).
Fit Facts: Healthy Hydration.