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- Newsgroups: rec.running
- Path: sparky!uunet!utcsri!torn!maccs!mcshub!nimios!krasnor
- From: krasnor@nimios.eng.mcmaster.ca (Carl Krasnor)
- Subject: Re: To wear a shirt or not?
- Message-ID: <1992Jul28.202853.22746@mcshub.dcss.mcmaster.ca>
- Sender: krasnor@McMaster.CA (Carl Krasnor)
- Nntp-Posting-Host: nimios.eng.mcmaster.ca
- Organization: Communications Research Laboratory, McMaster Univ
- References: <1992Jul27.101434.4374@verifone.com> <92124@bu.edu>
- Date: Tue, 28 Jul 1992 21:14:11 GMT
- Lines: 37
-
- In article <92124@bu.edu> dmf@buengf.bu.edu (David Franklin) writes:
- >
- >I have been told by former coaches that running with a shirt on will decrease
- >the rate of water evaporation from the skin. This in turn will decrease the
- >rate of dehydration. So if you want to run in hot weather without a shirt on,
- >you probably should be careful to hydrate yourself frequently during the run...
- >
- >---B-O-S-T-O-N---U-N-I-V-E-R-S-I-T-Y-----------------------------------------
- >-------------------------------C-O-L-L-E-G-E---O-F---E-N-G-I-N-E-E-R-I-N-G---
- >
-
- Wrong! Wrong! Wrong! You oversimplyfy and come to a false conclusion. If you
- are correct that a shirt will decrease the rate of evaporation, then wearing
- a shirt will INCREASE the rate of dehydration. Your body dehydrates via
- perspiring and perspiring is a response to elevated body temperature. The
- reduced evaporation rate you refer to reduces the rate of cooling and the
- body will compensate by sweating MORE. Your body has no sensors to check that
- the skin is already wet.
-
- To convince you further, another factor which decreases evaporation rate is
- increased humidity. No one would try to argue that elevated humidity levels
- reduce your rate of dehydration during a run. (However this may be true for
- a lettuce in the fridge!).
-
- To take your logic to its absurd conclusion, if one were to wear a snug
- body suit made out of latex rubber, one should be able to cover enormous
- distances without water.
-
- To summarize, in the heat, runners should do everything possible to
- FACILITATE evaporation of perspiration from the skin and this will
- MINIMIZE the rate of dehydration!!!!!
-
- --
- ===============================================================================
- Carl Krasnor, Communications Research Lab, McMaster U., Hamilton, Ont. CANADA
- krasnor@McMaster.CA VE3EGK Tel:(416) 525-9140 x4171 FAX:(416) 521-2922
- ===============================================================================
-