In Zen, there is a trance-like state called “makyo” (which is considered to be an evil conception like dark forces) in which all the senses in the body become acute.

It is said that a light-like substance actually appears on the retina, but some believe that it is simply a firing phenomenon in the visual cortex of the brain.

And that something similar can be reproduced by saunas.
Although I have never reached such a state, I think it is not a bad idea to have a trance-like state of self-affirmation in the face of the uncertain corona disaster.

According to Ichiro Ishii, M.D., Professor of Internal Medicine, International University of Health and Welfare Hospital
The possibility of a tranquilizing or psychological effect from sauna bathing has been reported for 30 years.
In recent years, it has become increasingly clear that the effects of serotonin, oxytocin, and β-endorphin in the blood, mainly in the brain, are linked to the central nervous system and autonomic nervous system.

It also affects the immune system, which may make it harder to catch colds. This may be similar to the traditional medical treatment of kampu friction and the traditional practice of waterfalls by ascetic monks as a way to ward off illness and prevent colds.

Modern medicine focuses on this as a mechanism of correlation between the nervous system, the endocrine system, and the immune system.”

Beta-endorphin: Has analgesic and anxiety-reducing effects similar to morphine used in cancer treatment.
Oxytocin : Relieves stress and brings about a happy mood.
Serotonin : Improves depression and mental stability.

The “tonou” of sauna actually has the same effect as the “enlightenment” of Zen.

◆ Reference
What does it mean to be “toned” to trance in a sauna? I asked a medical doctor who is familiar with hot springs.
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