Does your body temp drop after taking a leak?

[McRhea]

This is mostly concerned with males. Sorry Holly. Anyway, does your core body temp drop after taking a leak, going to the bathroom, draining your dragon, watering the tree? (hehehehe)

I'm living in South Korea for a while, and all the girls here say that a male's body temp DOES drop after going to the bathroom. All the guys say that it DOES NOT drop though. I'm in the middle... Both arguments have legit points... sooooooo.....

What say Ye? And can you back up your opinion with some valid scientific proof please? I have 1000 dollars, yes, that's right, 1000 dollars riding on this bet.

[Rags]

McRhea,

It is funny you should ask this. In a biology course I took at college, we had the very same discussion. It seems that when you take a leak, your perception of temperature changes due to the relief from nerves, making you feel colder. Now, when you urinate, your body uses many different muscles, and using muscles burns calories, and what happens when you burn calories? Heat is let-off. Thus your body temp rises. The urine in your body is the same temp as your body when it leaves you, but since it is not a heat generating source, the sole act of it leaving your body has no effect on your average body temp, but the muscles that have to work to get it out of your system does raise your body temp, albeit by a small amount, but it is measurable, and is different for every person. Now, this is assuming that we are two bodies sitting next to each other who have been in a normal state (not excercising before), and at their normal body temp before urination. Simply put, urinating warms your body.

Rags

[McRhea]

Yes!! Although no one here had it right, I'm glad I don't owe anyone 1000 dollars!
Thanks Rags.

[Paddy]

Actually, urinating can only involve the relaxation of muscles (detrusor/urethral sphincter specifically) only, therefore you may not get any heat generated from that.

I suppose that you could measure the friction being generated by the passing of the urine, but that would be silly.

Bottom line is you are moving a large ammount of warm fluid out of your body. Although the urine is not generating heat, you still loose heat through it.

Core temperature is essentially blood temperature, urine is essentially an ultra-filtrate of plasma, therefore it will be the same temperature.

The passage of this hot (37.4'C) fluid will warm the external genetalia, therefore men will feel warmer, but as it corresponds to a loss of fluid - you should actuall get colder (also remembering that water has an unusually high specific heat capacity)...

So, yes urinating will cause a slight reduction in body temperature - although the nerves to your bladder and various other parts of your body are autonomic and they cannot detect heat only the sensation of pressure.

So although you get colder, you cant feel it.

Unless you dribble down your leg.... in which case the urine should be warmer that your leg, so you therefore feel warm...

aaaagh!


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btw, I have not looked at physics since I was 16 - so i could be talking a big pile of poo!

[This message has been edited by Cheggers (edited 13 March 2000).]

[cjolley]

My sugestion is that none of you become science teachers any time soon.
1, Your body temp does not go up with mild exercize let alone the "work" of peeing.
2, Loosing fluid that is the same temp as the rest of your body does not affect the temp of the remaining fluid in your body.
chuck

[Paddy]

see i know i was talking poo!

I can cope with anatomy but not physics.

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"trust me i'm not a doctor"

[This message has been edited by Cheggers (edited 14 March 2000).]

[Rags]

Sorry Cjolley, but yes your body does generate more heat any time a muscle is moved. Even if your excercise is anaerobic, there is oxygen in your blood stream that will be sufficient for your body to create heat anytime ANY muscle is moved, there is proof that just the mere act of kissing burns calories (when calories are used up, heat is produced).

And Cheggers, you are correct that the muscles that control your urination do relax, but the act of them relaxing then restricting, relaxing, then restricting (which they do throughout the entire urination process) in addition to the other involuntary muscle movements (in your ass, toes, legs, and your sphincter) all contribute to burning of calories.

Rags

[Paddy]

So Rags, what do you do besides engineering?

Patrick

[Rags]

LOL, I do all kinds of things. Right now my main employment is working on cars. But I design software (very little), consult for an engineering firm here ocassionally when needed. My first major was Pre-Med until I realized I cannot stand being around other people's bodily fluids (which makes it hard on me being a single father). I also build computers for people I know and people they know. I also do tea parties for my daughter when the need arises

Rags

[Paddy]

Well,
Going on your scientific background, would it be fair to say that:

• Your body does more work retaining urine than it does expelling it?

Only going on the fact that people who have abdominal surgery quite often become incontinent due to damage of the pudendal nerve. Therefore they can't retain urine as they have lossed the coordination required...

I believe that once your bladder reaches a critical volume, it becomes more pf an effort to retain the urine rather than to expell it.

Therefore, by urinating you are conserving energy you would normally use to retain the urine - therefore by urinating you are increasing the avaliable energy overall and therefore heat?

God this has got my head twisted.

Right, i am off to bed (1:34 am) as I have a neuro exam on friday.

Cheers for the comments, what do you think?


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as allways, any information disclosed may be entirely crap

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trust me i'm not a doctor

[HedsSpaz]

Good points guys. Heres another one to consider. One of the first things you learn when you do cold weather camping is that if you have to pea, do so. You'll be warmer after you do so.

So, heres the reasoning for this. Liquids, and especially water, which is what uring mostly is, soak up heat very rapidly. So by not peaing, you are to a certain extent "losing" heat. Actually it's just sort of being relocated to your urine. Which is why urine is so warm. When you release it however, while there may initially be a loss of heat, very quickly your net temp goes back up becasue the water in your bladder is no longer absorbing it all.

So, thats why when you're lieing in your sleeping bag and you're cold and you have to pea, you get up and do so, cause while it may make you cold for 5 minutes or so, within 15 minutes you'll be much warmer than you were.

And on that note, I'm going to go practice what I preach....

[paulcs]

Someone should solve this by taking hsi temperature before and after. Of course, washing your hands afterwards would most likely reduce your temperature. And you'd have have to wash your hands before sticking something in your mouth.

Then again, there are alternatives to oral thermometers.

Maybe one of the married guys could ask his wife to help us solve this problem. For the sake of science, of course.

Paul
paulcs@flashcom.net

[cjolley]

Hmmmmm. There seams to be a basic confusion here about the difference between heat & temperature.

1. Your body has systems that keep your temperature constant despite variations in its heat output over time. The muscles that contract produce some heat as a byproduct, but your body acts like a giant heatsink & fan to get rid of it. (Had to reconnect this to computers)
Experiment: Take your temperature, take a long walk, take temp again.


2. The heat that your body looses in the fluid that you pee has nothing to do with the temperature of your body!
Experiment: Take your temperature, take a pee, take temp again.

I can't stand it.

chuck

btw. This has nothing to do with whether or not you feel warmer or cooler after peeing.




[This message has been edited by cjolley (edited 14 March 2000).]

[Paddy]

Liquids, and especially water, which is what uring mostly is, soak up heat very rapidly

Water as an unusually high specific heat capacity, therefore any heat produced within your body can go to heat the urine up. However, if the urine is not there (ie. having a wee wee) then that heat can go else where?

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I still think that when you bladder reaches a critical volume, it takes more energy to retain it (sphincter and urethral constriction) than it does to expell it (sphincter and urethral relaxation).

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Another confusion is the concept of core temperature. Your core temp is significantly higher than that of your forhead, mouth etc...
therefore the only way to accurately measure it is to swallow a probe (either up or down )

Your core temp should not be affected regardless, as urination occurs at an essential peripheral part of the body (some men more than others!).

And as i said earlier, regardless of what actually happens, as the nerves which supply the urinary tract are autonomic (you cant control them) therefore you can't feel the heat anyway?

I have noticed that you feel warmer when you urinate, but that could be due to the cutaneous nerves around the skin of the dangly bits 'sensing' the warm fluid below...

I can only speak from an anatomical and physiological point of view and physics are way beyond me so who knows!

Whatever actually happens, the potential temperature change is going to be so small that it wont be measurable, especially with a rectal thermometer (which wiuld be the best one to use!)

Patrick

[Jorden]

Okay, so this means we can kill McRhea by now for bringing this up in the first place??

Does this even belong in the 'Box?

A rectal thermometer might not do, but what of an IR-thermometer? Or a body thermometer?

Jord.