I’m curious about the cold water immersion technique that is used for physical and mental health. In particular I see all these videos of people getting in lakes with ice on the surface or in bathtubs full of ice and liquid water. Nearly freezing water, so around 1c to 2c. That’s really cold. I have gone swimming in water that cold, I’m not a fan.

So how long should we be in cold water and how cold should it be? Turns out it’s longer and warmer than i thought.

According to this research review the water should be 10c to 15c and immersion should last 11 to 15 minutes.