From: jbrandt@hpl.hp.com (Jobst Brandt)
Newsgroups: rec.bicycles.racing
Subject: Re: Keep knees covered in cold weather
Date: 9 Jan 1999 01:07:58 GMT

Robin Hubert writes:

>> On the other hand, if you are wearing tights made of the right
>> material, like lycra/polypro blend, it wicks the moisture away from
>> your skin while keeping you warm.  The fibers don't soak up a lot
>> of the moisture-it evaporates into the air, since it is usually
>> warmer than the ambient temperature.

> You believe that marketing crap too, eh?  Explain to me how wicking
> moisture away from the body, to be evaporated into thin air, can
> help conserve heat, especially when the water leaving the skin
> starts at 98 degrees F or so.  Any water that leaves the body is
> taking heat with it.

How about looking at materials in general.  Cotton of the same weight
and weave as wool is decidedly colder for the perspiring body than
wool because it holds water better and draws the evaporation process
out longer.  Even if you believe this takes place through different
means, I think you will agree that there is a difference between
materials.  On that basis, you might consider that there are better
materials than wool.  In fact that is why wool is not used much in
bicycling today.

If you have washed polypropylene in a conventional spin-dry wash
machine, you may have noticed that it comes out practically dry while
the remaining clothing is heavy and wet, ready for the clothes dryer.
This is the feature of the material that makes it desirable for sports
clothing.  Unfortunately, as with peanuts on airplanes that adversely
affect some folks, some folks stink in polypropylene, so we can hardly
find it on the market anymore.

> Perhaps this miracle fabric acts like a heat pump and takes the heat
> out of the water and puts it back into your body?  The fabric works
> as a heat sink?

Dry clothing is warmer than wet clothing and I, for one, prefer
polypropylene to other materials for its comfort and durability.  If
you attend local century rides in the SF bay area, you'll find many
riders still wearing the shorts and jerseys of polypropylene that
haven't been made for more than 20 years.  The stuff is durable and
comfortable.

Jobst Brandt      <jbrandt@hpl.hp.com>