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  #1  
Old 12 June 2008, 09:34 PM
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Icon204 Fanning makes you hotter

Comment: I have heard recently from people who I work with that fanning
myself with an improvised paper fan (or any hand-operated fan, for that
matter) will only serve to make me hotter. They claim using the energy
will heat me up. I disagree, because although I am using energy and body
heat is inevitably produced, it is being expended in one of my
extremities, so I think it would not have any noticeable effect on me. I
never feel anything but cooler, and I normally fan only my face and neck.
I'm not entirely sure which side is right.
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  #2  
Old 12 June 2008, 10:43 PM
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I was always told this by teachers in elementary school when the kids would make paper fans and start fanning themselves on hot days. I've always doubted its veracity.
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  #3  
Old 12 June 2008, 10:52 PM
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But the energy expended is not limited to the extremity moving the fan, you heart rate will rise, you will start to metabolise food more quickly etc etc....

I'm not sure how the balance works out, but I would postulate that the benefits would reduce the longer you fan yourself for...
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  #4  
Old 12 June 2008, 11:08 PM
BamaRainbow BamaRainbow is offline
 
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I think as a technicality, fanning yourself does make you hotter, but then so does eating ice cream (or, indeed, consuming nearly anything that has calories). What you're doing when you fan yourself is to create some air circulation which would presumably help evaporate the sweat your body's producing and the circulation of air is what helps. (Especially if you're sitting in an un-air-conditioned Southern Baptist church in the Deep South in the middle of summer on a Sunday listening to the preacher go on and on for hours and all you have at hand is a fan while you're sitting there in your "Sunday best" and feeling like that preacher's description of hell might actually be a pretty inviting place, after all.)
It's pretty well-known that fanning your face creates a mostly psychological reaction that helps you feel cooler (if your face is hot while the rest of the body is relatively cool, you'll generally feel less comfortable than if the reverse applies).
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Old 13 June 2008, 12:26 AM
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It would depend on how vigorously you wave the fan.

I know that sounds like a silly or sarcastic answer, but it's true. If you move the fan gently, just enough to move air across your face -- or, perhaps better, your chest -- then you benefit from evaporative cooling at a very low cost in increased metabolic activity. So, sure, if you vigorously flap a big towel up and down, you're probably gaining more heat from the exercise than you are from evaporative cooling...but if you just flap a little hand-fan up and down gently, you could, indeed, be achieving more cooling than heating.

It isn't a violation of the laws of physics, either: the energy goes into the state-change of water itself. The transition of water from liquid to gas involves a really surprising amount of energy. Your body is paying for it simply in "wicking" the water to the surface of your skin.

(I think that the capillary effect is also in play, but I do not know exactly how that is accounted for -- a debit or a credit -- only that the books always balance...and that sometimes, you can trick the other guy into paying. Ultimately, "the other guy" is almost always the Sun.)

Silas
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Old 13 June 2008, 12:57 AM
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Coincidentally, this morning I was fanning myself with a small index card while standing outside waiting for the library to open. After about a minute I stopped because the small amount of air flushing against my face was not enough to compensate for exertion of energy I was putting into the act. Had I been using an actual fan instead of a piece of discarded library card catalog, I might have been a little cooler (in more ways than one).
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  #7  
Old 13 June 2008, 01:09 AM
DaGuyWitBluGlasses DaGuyWitBluGlasses is offline
 
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Also your arm is more effective in venting heat than almost all other parts of your body (due to increased surface to volume ratio) .. so the heat being generated jsut below the elbow, isn't necessarily going to make it you your core. I.E. even if you were to generate more heat than is being removed, it wouldn't necessarily raise your core temperature.
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  #8  
Old 13 June 2008, 03:34 AM
Singing in the Drizzle Singing in the Drizzle is offline
 
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You need to factor air humidity as well. If you fan your self in a hot August day in the South East with 99% humidity it is not going to help evaporation any. Other the other hand some place like Phoenix AZ with 100 deg. temps and very low humidity the fanning works well.
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  #9  
Old 13 June 2008, 04:53 AM
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Quote:
Originally Posted by BamaRainbow View Post
I think as a technicality, fanning yourself does make you hotter, but then so does eating ice cream (or, indeed, consuming nearly anything that has calories).
Are you sure about this? I find it hard to believe that eating a frozen confection, no matter how calorie-laden, will raise your body temperature.
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Old 13 June 2008, 06:07 AM
Troberg Troberg is offline
 
 
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Isn't the idea that the fanning should be done by servant girls in thin, transparent veils? Of course, that doesn't exactly cool one down either...
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  #11  
Old 13 June 2008, 08:48 AM
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Quote:
Originally Posted by Cervus View Post
Coincidentally, this morning I was fanning myself with a small index card while standing outside waiting for the library to open. After about a minute I stopped because the small amount of air flushing against my face was not enough to compensate for exertion of energy I was putting into the act. Had I been using an actual fan instead of a piece of discarded library card catalog, I might have been a little cooler (in more ways than one).
That's what happens to me. I've fanned myself with a bus ticket before now. Not very effective.
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  #12  
Old 13 June 2008, 09:09 AM
Jay Tea Jay Tea is offline
 
 
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Ponder

For 'fanning' I read 'farting'.

After the chili and Guinness which made up last night's repast, I was thinking "Gee you're not wrong!"
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  #13  
Old 13 June 2008, 09:11 AM
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Quote:
Originally Posted by Troberg View Post
Isn't the idea that the fanning should be done by servant girls in thin, transparent veils? Of course, that doesn't exactly cool one down either...
Also palm leaves should be used as fans.
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  #14  
Old 13 June 2008, 09:12 AM
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Quote:
Originally Posted by Esprise Me View Post
Are you sure about this? I find it hard to believe that eating a frozen confection, no matter how calorie-laden, will raise your body temperature.
I've heard that before, although I don't have a cite.

A nice hot cup of tea, on the other hand, always seems to cool me down.
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  #15  
Old 13 June 2008, 10:55 AM
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I subscribe to the keep-as-still-as-possible school of thought on keeping cool. I'm not sure it fanning heats you up more than it cools down but I know that if someone is flapping about on a busy tube on a hot day they certainly raise my temprature- why can't they keep still!
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  #16  
Old 13 June 2008, 10:56 AM
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Quote:
Originally Posted by Red Squirrel has Returned View Post
I subscribe to the keep-as-still-as-possible school of thought on keeping cool. I'm not sure it fanning heats you up more than it cools down but I know that if someone is flapping about on a busy tube on a hot day they certainly raise my temprature- why can't they keep still!
Sitting still certainly works better but the stress of being hot tends to make you want to move around.

Also when I'm sat still I can almost hear myself sweating. Lovely.
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  #17  
Old 13 June 2008, 11:05 AM
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Quote:
Originally Posted by Syllavus View Post
I was always told this by teachers in elementary school when the kids would make paper fans and start fanning themselves on hot days. I've always doubted its veracity.
This is the only other time I've ever heard it, too. Followed by a thwack with that damn saints dictionary that hurt like hell. >giggle<
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  #18  
Old 13 June 2008, 12:07 PM
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Quote:
Originally Posted by Tarquin Farquart View Post
Also palm leaves should be used as fans.
Handled by scantly clad young Nubian boys (if you happen to be called Cleopatra).
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  #19  
Old 13 June 2008, 12:09 PM
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Quote:
Originally Posted by Floater View Post
Handled by scantly clad young Nubian boys (if you happen to be called Cleopatra).
I don't mind who's handling them as long as they keep me cool.
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  #20  
Old 13 June 2008, 12:56 PM
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Quote:
Originally Posted by Syllavus View Post
I was always told this by teachers in elementary school when the kids would make paper fans and start fanning themselves on hot days. I've always doubted its veracity.

You too huh?
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