How much should you drink when exercising?

Found this on the interweb, I have no idea if it's accurate, legit, kosher or believable in any way.

"How much you should drink when exercising to cover your body's fluid requirements depends on many factors. The nature of the activity is decisive. Jogging, cycling, aerobic, rowing, cross-country skiing and similar activities require lots of energy for moving, which makes you sweat a lot and lose a lot of fluid that has to be replaced in your body so that it can work at its best. Activities such as yoga, workout and some kinds of dancing are not as energy-demanding and consequently produce considerably less sweat. During and after such activities, you therefore do not need to drink that much. The rate of stomach evacuation, that is, the rate by which water gets from your stomach to your intestines where it is absorbed in your bloodstream, is 2½ dl per 15 minutes. This means that at maximum 2½ dl of water can be moved from your stomach to your intestines per quarter of an hour of exercising - no matter how hard you exercise. It is therefore not useful to drink more than 2½ dl per 15 minutes, it will just make the water slosh around in your stomach and possibly make you uncomfortable. Some activities such as jogging can, however, easily make you lose 2-3 l of water per hour, depending on the temperature and how fast you jog, and it is not possible to keep up with replacing the loss. To ensure an optimum hydration of your body during activity, you need to drink enough during the hours preceding exercising. If you are in deficiency already before jogging, for instance, your performance will be considerably reduced. The rate of stomach evacuation can be further reduced if nutrients such as salts and sugar are added to the water. So, if you are going to exercise long you should consider whether the most important thing to do is to drink as much water as possible or whether you should also get some salt and sugar so that you will not risk getting a sugar level that is too low."

If true ..... you can absorb 1 litre per hour but can obviously sweat way more than that. So .... for a 4 or 5 hour stint I'm guessing I should have 4 or 5 litres of liquids on standby, with the *right* balance of electrolytes, salts and sugar (whatever), and make sure I'm hydrated fully in the couple of taper days beforehand so my pee is nearly clear. That sounds about as good as it's going to get. And deal with the consequences afterwards ... so have a couple more litres of recovery juice waiting at the finish line. And a beer !!

Sorted! Just need to get fit now :)