| Take your water with a pinch of salt
I've been reading this group for about a week, now, and I feel I must
post to point out that some advice being dished out here is complete
and utter nonsense.
In various threads I've seen people state that you should drink x
litres of water per hour (or x/3 litres per 20 minutes, or whatever).
Now, just think about this for a moment. Someone is advising everyone
who reads this ng, that they require a certain rate of liquid intake
to maintain correct hydration.
Does that seem to make any sort of sense? If it does, think about it a
little more.
Q: Why does one need to keep drinking water on a ride?
A: To replace water lost by perspiration. (We also lose a little
because exhaled breath is wetter than inhaled).
Q: Why do we perspire?
A: To cool down.
Q: What factors affect the amount we need to perspire in order to
remain at an acceptable temperature?
A1: Body size
A2: Velocity
A3: Ambient temperature
A4: Ambient humidity
A5: Clothing
A6: Wind
A7: Weight of cycle
A8: Efficiencly of cycle
A9: Expertise of rider
All of these things will affect how much sweat we need to produce.
The difference in fluid intake requirements between:
a) A 45 kg woman cycling expertly at 10mph in cool non humid
conditions with just enough clothing to keep warm on an efficient,
lightweight cycle,
and
b) A 120kg man cycling inexpertly at 20 mph in hot humid conditions,
wearing more clothing than necessary a poorly maintained heavy cycle.
Will certainly exceed a factor of 10 (much more likely to be nearer
30).
Hydration *is* important, and should certainly not be taken lightly,
and it is true to say, that, within reason, too much is better than
too little.
Having said that, if you see a recommendation, *any* recommendation,
that specifies a certain rate of consumption without any
qualifications based on the factors mentioned above, *please* do not
take it seriously. Even being as charitable as possible, one cannot
say other than that the person making the recommendation hasn't a clue
what they are talking about (although of course, the figure given may
be spot on for themself, and the conditions under which *they* cycle).
Even to give a figure (3 litres per hour is often quoted), and say
it's a "base", is really nonsensical given the actual possible range
of "correct" values.
I don't know if anyone has produced a set of charts based on body
weight v speed v ambient temperature (which should be good enough for
a starting point). If not, the best way to check is to observe the
colour of your urine at the end of a ride. If it is noticably yellow,
then you should drink a little more water as you go. If it is orange,
you are drinking far too little. Remember that it is very easy to
become dehydrated before you feel thirsty, but don't force yourself to
drink amounts of water that make you feel uncomfortable.
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