Read this before the hype
What heat and cold actually do.
There is a lot of big talk online about saunas and ice baths. Some of it has good research behind it. A lot of it does not. Here is our honest version, written by people who run a bathhouse, not doctors.
What happens in your body
Heat speeds you up. Cold does too, then you settle.
In the sauna your skin warms, blood moves toward it and your heart rate climbs, a bit like a brisk walk. In cold water your blood vessels tighten, your breathing jumps, and after the first half minute most people calm down.
Resting after both is when your heart rate drops back. That swing, up and down, is what people mean by contrast. It is a real, measurable thing. What it does for you long term is a much more open question.
The evidence, sorted
What studies suggest, and what they do not prove.
Most sauna research comes from long running studies of people who already used saunas often. That shows a link, not a cause. Cold water studies tend to be small, short and on young men.
What studies suggest
- People who use a sauna often tend to report better sleep and lower stress.
- Large observational studies have found a link between frequent sauna use and heart health. They cannot show the sauna caused it, and the people studied were mostly healthy already.
- Many people report feeling more awake for a while after cold water.
- Many people say a cold plunge after exercise leaves their legs feeling less sore. The research on this is mixed.
What they do not prove
- That a sauna will prevent or treat any disease.
- That cold plunges burn meaningful fat or boost your immune system.
- That longer or colder is better. There is no evidence that 3 minutes at 45 F beats 1 minute at 55 F.
- That any of it replaces sleep, movement, food or your doctor.
When to stop
Get out, sit down, tell us.
Leave the room straight away and find a staff member if you feel any of these. Nobody will think twice.
- Dizzy, light headed or sick to your stomach
- A pounding or uneven heartbeat
- Chest pain or trouble catching your breath
- Numb hands or feet that do not warm up after the cold
- Shivering that will not stop after ten minutes of rest
How guests say it feels
The part no study measures well.
We asked regulars to describe a good visit in a few words. These come up again and again.
- Calm for the rest of the day
- Slept like a stone
- Head cleared out
- Proud of the cold
- Loose shoulders
- Hungry, in a good way
Not medical advice. If you are pregnant, have a heart condition, high or low blood pressure, or take medication that affects heat, check with your doctor before you visit. Our first visit page covers the rest.