It is important to drink little and often to keep hydration topped up every hour! It isn't adviseable to drink it all in one go! It is best to sip water through the day and never drink more than 2 pints in one hour. Do not excede 6 pints in any day. If you are a runner or professional athlete then you may need to trust your judgement and drink more than that but never excede 6 pints, but on average, 4 pints (or 2 litres) of water per day is recommended for the average person.