If you’ve ever been in a steam room, you’ve probably noticed that your skin is quickly covered in water droplets. So, does that mean that you sweat more in the steam room than a sauna, or is that just water on your skin?
People sweat more in a steam room than in a sauna. This is because the air is completely saturated with water, therefore your sweat is unable to evaporate. This matters because evaporation is how sweat works to cool you off. So, your body will continue to heat up and sweat more in an attempt to cool off – at a much higher rate than drier conditions.
Perhaps you already knew that sweat works by evaporation. But did you know the exact science behind why that works, exactly how much sweat is lost in a sauna, or how to tell for yourself how much you are sweating? Read on to learn more!
Do people produce more sweat in a steam room or a sauna?
Anyone who has used a steam room has probably wondered at some point if the water droplets on their skin are sweat or just a collection of the water vapor. Simply put – it’s both a combination of sweat and condensation, where water droplets from humid air collect on a surface with a cooler temperature (your skin).
Naturally, that brings us to the next question. How much of those droplets are sweat, and how much is condensation? The answer depends on the conditions of the sauna as well as your individual tendency to sweat, but it’s probably more sweat than one might think!
I can tell you with certainty that if two environments are of the same temperature but one is a steam room, you will definitely sweat more in the steam room – it’s just physics!
Are you the type of person that needs to see it to believe it? Then keep reading – we’re going to dive deep into why, and even teach you how to conduct your own experiment!
Why do you sweat more in a steam room than a sauna?
Sweat goes hand in hand with steam rooms and saunas, so why is it that steam rooms make you sweat more than saunas? In a steam room, the air is fully saturated with water vapor.
Because of this, your sweat has nowhere to go and it stays on your skin. Your body continues to heat up and sweat in an attempt to cool off, producing even more sweat that continues to collect on the skin.
This happens because, in order for sweating to actually work, the sweat needs to evaporate. It can’t evaporate into saturated air, which continues the cycle of sweating. For this reason, you will always sweat more in a steam room than a sauna of equivalent temperature.
How does sweating work to cool you down?
When you sweat, it cools you by evaporation. This phenomenon is called evaporative cooling, and any substance that water evaporates from loses heat in the process.
So, how does this work? On a molecular level, heat exists as thermal energy. When water changes from liquid form to gas form, it has even more thermal energy. Thermal energy exists as a form of movement or kinetic energy.
Imagine the particles bumping around – the faster they move, the hotter the substance. Water moves faster in gas form, and as your skin heats up, the water molecules in your sweat “speed up” until they turn into gas (or in other words, evaporate).
That energy of movement has to come from somewhere – and in the case of sweating, that energy comes from your skin. So, as the thermal kinetic energy from your skin “transfers” to your sweat, it then evaporates once it has “collected” enough thermal energy from your skin. Think of it like a row of dominos or Newton’s cradle.
In turn, you cool down as the water in your sweat evaporates and removes heat from your skin. But, in a steam room, this phenomenon can’t occur because your sweat can’t evaporate into the saturated air.
So, how much sweat are we talking about?
How much do people sweat in a sauna?
Most people sweat an average of about a pint during a sauna session – wow! And within minutes, your skin temperature can reach 104° F.
How much do people sweat in the steam room?
Although the exact volume of sweat in a steam room hasn’t been measured, there is a plethora of scientific evidence that we sweat more in more humid environments. There is a strong, measurable correlation between humidity level and sweat rate.
Given that the average level of humidity in a steam room is around 100 percent, versus the average five to ten percent humidity of the sauna, the simple answer for how much we sweat in a steam room would be: more than we do in a sauna of the same temperature.
So, if we sweat about a pint in the sauna, it’s likely that you’d be sweating more than a pint in a steam room.
We all know what that means – hydrate, hydrate, hydrate!
How can I see for myself how much I sweat in a steam room or sauna?
If you’re interested in a spa experiment, there are ways to calculate exactly how much sweat you’re losing. Measuring your own sweat rate is a fairly simple process.
First, you’ll need some equipment:
- An accurate body weight scale
- A dry towel
- An accurate handheld scale
Then, you’ll need to follow these steps:
- Measure and take note of the weight of the water you plan to drink. Be careful not to include the weight of the bottle with the water weight – then your results would be inaccurate. You can use the “tare” function on the handheld scale, or just measure the empty bottle then subtract the weight of the bottle from the total weight.
- Be sure to fully empty your bladder.
- Weigh yourself, and take note of your weight.
- Go enjoy your sauna session!
- When you’re done, you’ll need to towel yourself off completely dry, as dry as you can possibly get yourself.
- Weigh yourself again. Add the weight of the water you drank to both weight measurements. Then, subtract your second total from the first total. It would look like this: (First Weight + Water Drank) – (Second Weight + Water Drank)
And now, you’ll have a measured amount of exactly how much sweat you lost! So, if you really want to know exactly how much more you would sweat in a steam room, that’s how you would do it. You would just repeat these steps between each room and compare the difference.
I’m not great at math. Can I still tell how much I sweat without the calculations?
Yes! There are other ways to undergo your own spa mini-experiment without having to do much (or any) math!
Biometric scales use a technology called bioimpedance to measure your muscle mass, fat, body water levels, bone mass, and more. You can use biometric body weight scales to measure the difference in body water composition before and after the steam room or sauna.
There are many options out there at different price points, they are pretty accurate and good ones can be found as low as around $30, like this one. It will do the trick just fine, but if you want all the bells and whistles, check out ones like this, or even go all out with this one.
The way you would find out how much you’ve sweat with this type of scale is more straightforward than the bodyweight method. You would simply step on the scale and take note of how much water is in your body before and after the sauna. You still need to account for the water you drink, so this is how you would do it with a biometric scale:
- Hydrate yourself beforehand
- Empty your bladder
- Weigh yourself, take note of body water levels
- Enjoy the sauna
- Dry yourself thoroughly
- Weigh yourself again, and take note of the difference in body water levels
There are also wearable devices (like this one!) that will tell you how hydrated you are, so you can easily get an idea of how much water you’re losing between the steam room or the sauna.
This is also a straightforward method, and you would take the same steps as with a bioimpedance scale. Remember, though it might be tempting to wear the device into the sauna and watch your hydration levels change in real-time, these devices are water-resistant but are usually not heat-resistant.
So, be sure to measure your body water levels before and after the steam room or sauna, then take note of the difference.
Everything is best in moderation, no matter which one you choose.
Both the sauna and the steam room have their benefits, but one thing is certain: We sweat a lot more in a steam room than we do in a sauna. As such, it is important to make sure you don’t sweat too much and dehydrate yourself. Remember, the goal is to relax and enjoy yourself – try not to overdo it, no matter which one you prefer.