Do cold baths use more calories ...

... than hot baths?

21 to 38 of 38 messages
17/11/2006 at 09:12
Well, FWIW - you'd presumably lose weat as the surrounding temp was lower (the cold water), and I'd guess that the body would try to compensate for this (homeostasis 8-), so it would have to get the heat energy from soemwhere. I do vaguely remember seeign somethign on one of the Royal Society Xmas lectures where they did an experiment like this

where's it going to get the heat from? It's a biological thing but I'd guess as a by-product of cellular respiration - i.e. burning whatever fuel was around
17/11/2006 at 09:14
you'd probably lose heat as well ;o)
17/11/2006 at 09:21
Isn't this a bit like the hot drink vs cold drink debate where people say that hot drinks actually cool the body down? What really matters is the temperature difference between the drink and your body so both hot and cold drinks will have a cooling effect (unless you mix them together first). Never been convinced by the idea that you need a hot meal in the winter for the same reason. My nan always used to say that she needed something warm inside her - she would sometimes say that she needed a banana just to fill a little hole. It wasn't easy keeping a straight face sometimes.
17/11/2006 at 09:41
What temperature is a cold bath normally at?
I guess it changes depending on where your cold water tank is and what time of year it is, but I'd be surprised if it where less than 10 degrees C. Apparently a bath holds 65-80 litres when completely full (so only half full for a cold bath?) and room temp of a bathroom is around 22-23 degrees. I'm also pretty sure that in if you stayed in it for around 10 minutes that the temperature only rises a couple of degrees rather than fully up to room temp. So we are talking raising around 30 to 40 litres (30,000 to 40,000g) of water by only a couple of degrees . One calorie (0.001 kcal) raises one gram of water one degree C
So, that equals 30 to 40 kcal per degree of raised temperature. I seem to remeber that the human body produces around 25-30 kcal per hour of radiated heat in a ambient room (though I could be making this bit up).
so the answer is , it probably makes bugger all difference. And none of the above takes into account that the water will be heated by the air temp and absorb heat through the sides of the bath etc.


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17/11/2006 at 09:55
I'm inclined to agree with you, Vrap.

Anyway, cold baths make my willy small.
cougie    pirate
17/11/2006 at 10:00
Jeez - you dont need that do you !?
17/11/2006 at 10:09
[shakes head slowly]

No sir, I certainly do not.
17/11/2006 at 11:20
FYI..
1 calorie (imperial measurement) raises the temperature of 1 ounce of water through 1 degree farenheit.
1 Joule (SI measure) raises the temperature of 1 gramme of water through one degree centigrade.

I don't know the answer to the question, but your body will react in two different ways surely? Cold water, blood vessels to extremities constrict to reduce heat loss. Warm water = vasodilation and body having to work harder (=sweating?) to try to prevent overheating.
17/11/2006 at 11:22
How about saunas? Much more fun than cold baths!
17/11/2006 at 13:58
Yes peashead I did have a cold bath after Dublin , first one ever and not a pleasant experience, it took me ages to get in, and I had to say too my self come on woman you have just run a marathon you CAN get in this bath of cold water, dont know about the calorie thing (although it make sense that your body is using energy ie caloreis to warm up,)but I really did recover quicker than after London, I would see it that, if you injure yourself you apply ice, so surly having a cold/icey bath would repair any miro muscle damage.
17/11/2006 at 15:56
There have been some cases of people surviving unscathed from near drowning in very cold water as their metabolism effectively shuts down. Assuming, however, that you don't get to that stage by taking a cold bath I guess that you would burn more calories through shivering in a cold bath than heating up in a warm one but can't find proof one way or the other
17/11/2006 at 16:16
I believe "studies have shown" that swimmers, for the same amount of effort expended
(measured as O2 thoughput)
have LESS of a tendency to lose fat than runners

and it's hypothesised to be because the immersion in cold (colder than body temp) water
causes the body to want to be protected by a nice layer of blubber

whereas getting all hot running makes the body
want to be less insulated.

Note the physiques of Inuits and Kenyans.

So I think cold baths will not help anyone get thin.

Clearly the basic thermodynamics that you'll have to expend energy
that dissipates into the water
must be true,
but the body has regulatory mechanisms that
compensate for that over the longer term.
IMHO.
17/11/2006 at 17:23
weighed myself before cold bath - 48.9 kg (yes, on the rather small scale of thin - nothing i can do about it, not matter what i eat)..........after cold bath and much shivering - 48.8kg. so there you go - proven that you lose weight in a bath. therefore i am not going to take anymore icy soaks or i might disappear and never be seen again.
17/11/2006 at 17:43
FF - specific heat capacity of water = 4200J/kg/degree, so 4.2J to raise temp of 1g water by 1 degree. Not that anyone really cares...

17/11/2006 at 21:33
<puts on D cap and goes to sit in the corner>
19/11/2006 at 12:02
pearplumpie, loss of .1 kg ? are you sure you just didnt have a wee to warm the water up ?
19/11/2006 at 15:56
no, ALWAYS do a wee before i get in the bath. too tempting to do it while sitting in ice cold water. tell children off for doing it in their WARM bath (not that cruel!), and besides i have to clean the bath - so no weeing in it.......!
19/11/2006 at 15:57
do you use calories thinking? have to make myself do a whole sudoku or other puzzle in a cold bath so i stay in for long enough - maybe it is the extra brain strain that causes the weight loss too?

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