I tried the cold shower method today.
I was actually laying in the bath for about 30 minutes, almost fell asleep. The water was warm. I felt kinda shitty, just like it says in the article, warm water doesn't make you feel good
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When I decided to go out of the bath, I showered myself with cold water. Each time, the water was colder. I rinsed my body with cold water and waited till I got used to the cold. Then, I repeated the process with colder water. I did that 4 or 5 times. In the end, the water was so cold the breathing became a bit more difficult and faster. Last time I only rinsed my legs and arms, with coldest water possible.
When I got out of the bath, after maybe 30 seconds, my body felt warm, and I felt BETTER.
You should definitely try this
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I will also try the breathing method.
In knowledge, there is power