Well, why would they feel good? It would make the most sense if people enjoyed being surrounded by water that would keep their body temperature the most constant (I am guessing 85-90 degrees?*). This would be analogous to the fact that most people like to be in air temperature of 70-80** degrees because it keeps us from overheating or getting too cold.
However, this doesn’t seem true for most people with water. I don’t have hard-core research to back this up but it seems that most people obtain pleasure from taking baths and showers where the water would NOT keep them at a constant temperature indefinitely. For example, there are several places online that indicate the “average” water temperature in a shower/bath is 105 degrees. We do that because it feels good.
So, here is the question: Why would our bodies like to be surrounded by water that is really “too hot” for us to be in very long?
For those unlucky enough to not live in the Bahamas, Belize, the Cayman Islands, Palau, and the United States (and associated territories) this translates to 29ish to 32ish.
** YMMV
air next to the body and water next to the body, either immersed or a steady shower, extracts different amounts of heat.
while showering or bathing you are also still and either loosing or gaining heat based on water temperature that is on your skin and the amount of water in contact.
A nice hot bath is only slightly hotter than body temperature - maybe 38-40C. Any hotter than that is pretty uncomfortable - even 45C is perceived as “scalding hot”.
So there is really not much temperature differential - and bear in mind that bath water cools down pretty quickly, so even if it starts out at 40C, it won’t stay that warm for very long.
Not everyone likes hot showers. I like very warm showers. I also don’t like hot tubs or swimming pools that are over 90 degrees.
I may be part of the minority, but except for the times I am extremely cold having been outside during the winter, hot showers and baths make be feel sweaty and clammy.
I think you would find a wide variety of temperature preferences for showers and baths if you canvased the world.
I wondered the same thing once and the conclusion I came to was its a homeostasis thing.
Our bodies often burn calories just to keep us warm. We lose alot of heat to our environment. When we immerse ourselves in an environment that creates a temperature where our bodies do not have to expend energy to warm or cool ourselves we find it very relaxing.
The variation in answers so far makes me think that maybe I didn’t word my thoughts correctly.
I realize that water does a much better job at transferring heat to/away from your body. So why does our skin/brain enjoy surrounding itself with water that is too hot to be sustained*. Our body could not stay in water that is 105 degrees or even 98 degrees (body temperature) for very long because the heat generated in our bodies could not be expelled. We would overheat.
Comparing the transfer of heat, this would be like surrounding yourself in 110 degree air for 10 minutes every morning. Most people would not enjoy that! Why is water different? There must be something programmed in our brains to like it.
*Maybe not everyone in the world enjoys hot showers, but I am pretty sure millions of people do.
"Heat opens up blood vessels, which increases blood flow and supplies oxygen and nutrients to reduce pain in joints and relax sore muscles, ligaments, and tendons. The warmth also decreases muscle spasms and can increase range of motion. Applying superficial heat to your body can improve the flexibility of tendons and ligaments, reduce muscle spasms, and alleviate pain.
How is it applied?
Sources of heat can supply either dry or moist warmth. Dry heat sources may dry the skin. Moist heat may penetrate better. Heat can be applied by an electric or microwavable heating pad, hot water bottle, gel packs, or hot water baths."
Essentially the answer is the dry heat of a 110 deg day isn’t as typically comfortable as a hot bath because it dries our skin and nasal passages. However there is some comfort in it though - hence why sauna’s are also popular.
The hot bath or hot tub does all of the above without any negative effects - the heat transfer is faster too.
Maybe it has less to do with temperature and more to do with being clean?
There are social advantages to being clean. Physically, cleaning yourself with soap of some kind generally removes excess dead skin and oils. My hair feels nice and light and ‘fluffy’ after its shampooed, rinsed and dried.
There’s this. When we are cold, we shiver: The muscles doing basically useless “make-work” just to burn energy and generate heat.
When we are hot, exactly the opposite happens: The muscles go into low-energy “power-saving” shut-down mode, to reduce the internal heat generation. That is why it is relaxing to be hot, and why hot weather makes people feel lethargic and floppy.
Most buildings are overcooled for my taste (including my home, which is set to a compromise between what my wife and I want.) I live in NC where it’s often over 100 degrees in the shade, and I always enjoy the first few minutes when I leave a cold room and hit the nice hot air. And then, of course, reality sinks in, in the form of heat, and I head back inside where it’s not so freaking hot!
With regards to a shower, only a small part of your body is being hit with the +100 F water in the first place, so your body would have no reason to feel uncomfortable (especially considering the muscle relaxing effect of hot temperatures).
With regards to a hot bath, most people can only tolerate being in a hot tub for only so long, and then it really does start feeling uncomfortable. For me personally, I enjoy a hot tfnordub if it’s nice and cool outside. Sitting in a hot tub on a sweltering summer day sounds like torture to me.
WAG: It’s an evolutionary holdover from the days before central air. A hot blooded creature that seeks heat will require slightly fewer calories to survive than one that is indifferent to external heat sources. True there aren’t many heat sources when food is scarce, but a patch of sun, a hot spring, or fellow hot-blooded creature could save several precious calories.
Because a little bit of pain doesn’t feel like pain, it feels like pleasure. Endorphins are released when hot water hits the skin to reduce the pain, and endorphins make you feel good. Stay in that hot water too long, and the body adjusts the blood flow and the endorphins stop, leaving you tired, and then you decide it would be nice to get out of the shower or hot tub or sauna and go jump in the cooler pool or a snowbank, because adrenaline.
This may actually be the right answer. Lizards are cold blooded and regulate temperature using external environmental changes.
While we do regulate our body temperatures we also maintain an environment based on a habit of wearing clothes. Take the clothes off and we are now cooler than normal in our preset environment. Showers feel good for a short period of time.
I had “heard” that some Japanese people take hot baths at like 160F. I was young when I heard this and I had no clue about how hot that actually was. I had assumed I was liking baths in the 120F range - I had no data to base this on, but the Japanese thing sounded awesome - and I figured I was not quite that awesome in my ability to withstand the heat - but still imagined myself at 120.
After all, I thought, I could easily withstand 100 degree heat outside, surely if I had to slowly lower myself into the tub thinking “HOT, HOT, HOT!” - it had to be at least 120. I knew that water and air were different, but facts were no obstacle to my strong belief it had to be way higher than body temp.
It wasn’t until I got my own place and a thermometer and had control over the water tank that I realized:
Fucking 140 degrees is hot as shit - my water tank is set at that and my thermometer reads that too if I use 100% hot water. There is no way I could stand this - as my hand instantly retracts. My 120 degree estimate was starting to lose some strength, but that is still 20 degrees hotter than what I had guessed.
I filled up the tub with the water super hot as I like it. It seemed to be a little tricky using an infrared thermometer with water (but it seemed to accurately peg the hot water at 140 - same as the tank said) - turns out my super hot baths I like - were around 101.
I constantly have to keep topping it up with hot water to keep it comfortably hot.