Experts advise healthy adults to sip water or other fluids throughout the day and to aim for an average of about 8 to 12 cups. That amount might vary depending on age, size, gender, activity level and medical conditions.
A sports nutritionist who worked with the Boston Celtics recently said he advises athletes to consume 80% of their fluids for the day by 4 p.m. to give their bodies enough time to process the liquid before bedtime.
This suggestion, reported by Business Insider, does not appear to come from any specific research, and may be too extreme or arbitrary to benefit most adults who are not elite athletes, according to dietitians
Source: The San Francisco Chronicle