Many people swear by short exposure to cold water and believe that’s enough. However, staying in too briefly has little effect, while overdoing it can be risky. So what’s the right amount of time for a cold plunge?
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Pain and Shivering Are Good Indicators to Stop
“The cold plunge should not exceed three minutes,“ explains Hanns-Christian Gunga, Professor of Space Medicine and Extreme Environments at the Charité in Berlin. Other sources speak of up to 5 minutes. As with saunas, it is not possible to say exactly when you should stop cold plunging. Ultimately, you should mainly listen to your own body. Once the cold becomes painful or you start shivering intensely, it’s time to get out.
Aim for 2 to 5 Minutes
To experience the benefits, you need more than a quick dip. Think of it like a workout or sauna session: just a few seconds won’t do much. The minimum time for a cold plunge, once you’ve built some tolerance, should be around 2 minutes. A range of 2–5 minutes is generally considered optimal for gaining the positive effects of cold exposure.
Dosage Guidelines from Russian Doctors Latyshev and Bokshej
Two Russian doctors created a table that shows how long you can safely stay in cold water depending on temperature and experience. The differences between beginners and trained people are quite significant. This means that cold water swimming tolerance improves with training. At a water temperature of 15 °C, for example, the two doctors say that a trained person can stay in the water approximately 30 times longer than beginners.
| Water temperature | Beginners | Advanced | Trained |
|---|---|---|---|
| 0°C | 5 – 30 s | 30 s – 1:15 min | 3 – 5 min |
| 5°C | 10 – 25 s | 45 s – 1:30 min | 5 – 10 min |
| 10°C | 12 – 35 s | 50 s – 2 min | 8 – 16 min |
| 15°C | 15 – 55 s | 1:15 – 4 min | 17 – 30 min |
This shows that cold water plunging can be trained over time, extending safe exposure.
A Simple Rule of Thumb
It is clear that the colder the water, the more training you need and the shorter you can stay in it. It therefore makes sense to look at these two parameters in relation to each other and use the following formula as a guide:
Water temperature (°C) = Time (minutes)
10 degrees = 10 minutes
9 degrees = 9 minutes
etc.
<= 2 degrees = 2 minutes
Scientific Table: Body Temperature Drop
If you want to do it scientifically, you can use the table below as a guide. It provides information about how quickly core body temperature drops in cold water.
The table can be read as follows: In the first column, you can see the water temperature and, depending on this, the bathing time to lose either – 0.5°C in body temperature or – 1°C. Obviously, the warmer the water, the longer it takes for your body to cool down by 1 degree Celsius.
It is interesting in this respect that the core body temperature (CCT) decreases exponentially with the water temperature. For example, at 20°C, it takes about 20 minutes for your body temperature to fall by 1°C, while at 10°C it only takes about 4.5 minutes.
| Water temperature °C | Temperature drop KKT in °C / min | Bathing time for -0.5°C KKT | Bathing time for -1°C KKT |
| 20 | – 0,05 | 10:00 | 20:00 |
| 19 | – 0,07 | 07:30 | 15:00 |
| 18 | – 0,08 | 06:00 | 12:00 |
| 17 | – 0,10 | 05:00 | 10:00 |
| 16 | – 0,12 | 04:17 | 08:34 |
| 15 | – 0,13 | 03:45 | 07:30 |
| 14 | – 0,15 | 03:20 | 06:40 |
| 13 | – 0,17 | 03:00 | 06:00 |
| 12 | – 0,18 | 02:44 | 05:24 |
| 11 | – 0,20 | 02:30 | 05:00 |
| 10 | – 0,22 | 02:19 | 04:38 |
| 9 | – 0,23 | 02:09 | 04:18 |
| 8 | – 0,25 | 02:00 | 04:00 |
| 7 | – 0,27 | 01:53 | 03:46 |
| 6 | – 0,28 | 01:46 | 03:32 |
| 5 | – 0,30 | 01:40 | 03:20 |
| 4 | – 0,32 | 01:35 | 03:10 |
| 3 | – 0,33 | 01:30 | 03:00 |
| 2 | – 0,35 | 01:26 | 02:52 |
| 1 | – 0,37 | 01:22 | 02:44 |
| 0 | – 0,38 | 01:18 | 02:36 |
Avoid hypothermia
First of all, what is hypothermia? Hypo is the ancient Greek preposition for “under” and thermos means “hot, warm, boiling”.
Hypothermia therefore refers to the underheating of the body – an abnormally low body temperature that can be caused, for example, by severe exhaustion, illness, or even artificially. Hypothermia, in other words, is defined as a core body temperature of 36°C or higher. The core body temperature refers to the temperature of your internal body. It’s defined as:
- Mild: 32–35°C
- Moderate: 28–32°C
- Severe: Below 28°C
If your temperature drops below 32°C, you should seek medical attention, as this can cause permanent damage or even death.
Humans have a core body temperature of approximately. 37°C. This means that hypothermia of just 2°C is the highest level of mild hypothermia. For example, in 3°C water, it only takes about 15 minutes for your core temperature to drop by 5°C—leading to moderate hypothermia. This is why staying too long can be extremely dangerous, even for trained cold plungers.
Studies show that people can hardly move for around 15 minutes after falling into an ice hole. The extremities, in particular, are no longer well supplied with blood, which means that you can also suffer frostbite.
Maximum: 10 Minutes for Experienced Cold Plungers at 5°C
So what is the maximum duration? At a water temperature of around 5°C, even experienced cold plungers should not exceed 10 minutes. According to our rule of thumb (water temperature = time in minutes), that would only be 5 minutes, so you would clearly exceed this guideline. That would mean a drop in core body temperature of around 3°C, which is achievable with training. But this should not be seen as a recommendation, because ultimately it’s about feeling comfortable both in the water and afterwards.
In practice, it’s best not to watch the clock too closely at first. Push past the initial shock, aim for at least 2 minutes, and build from there.
Remember: the biggest benefits come in the first 2–5 minutes. Beyond that, the risks increase while the added benefits diminish.
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