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The Ikigai Diet and Bio-Hacking
In my book Ikigai Bio-Hacking, I introduced river swimming and lake swimming because they have hormetic effects and can be a modern way of practicing Takigyo, sitting under a waterfall. However, I didn’t recommend that you do them in winter because it may be too hard and could be dangerous depending on the person.
On the other hand, thousands of people practice cold plunge or cold exposures all over the world now, some of them have been doing it as part of their tradition, others have taken it up as a new trend.
Wim Hoff method, for example, is very popular now.
Since I had been taking one minute of a cold shower for a few months now, which I combine with a hot bath in winter; I tried plunging in Lake Biwa last Sunday. It was a snowy day, and the lakeside was extremely windy. I mean, the wind was so strong that my bag was almost blown away.
Anyway, I took my clothes off and got into the water with my swim shorts.
God, it was cold. The moment I put my feet in the water, it wasn’t anything like taking a cold shower or having a cold bath after a sauna, it was freezing, and as I put my entire legs, the legs began shaking.
I was a little shocked because I didn’t think it was going to be that hard, having practiced my version of cold exposure for a while. I was even going to swim there. I thought the body would get used to the temperature after a minute or so, and I would be able to enjoy swimming for a few minutes after that.
No, I was naïve. I thought I would stop there, and that was what my body was telling me. Don’t be stupid, you don’t want to do that. But my mind reacted differently. You came all the way to the lake (1-hour drive) and not to do it? It is probably your last chance this winter because spring is on its way.
Okay, I pulled myself together and put all my body under the water, all the way up to my shoulders.
Goodness! It was much colder than a cold bath at a sauna facility. I mean, the cold bath was cold, but still bearable. This time, it truly was an austerity. I counted for 60 seconds. As I was counting, my legs were still shaking. 10, 20, 30. It felt longer than my regular cold shower and cold bath. 40, 50. I was still not used to the temperature. I thought I could go longer than a minute, but no, I had to stop after 60 seconds.
I slowly walked on the sand back to my bag, but it was still cold with the wind. I quickly took my towel out and dried the body. Then I took my clothes out and put them on, which was very difficult because of the wind. I had to be careful not to have them blown away.
I am sure I will get used to it, if I pick a less windy day and do it several times, but going through the process of taking your clothes off and putting them back on in cold air, I would choose a sauna over this, the Japanese-style sauna.
The Japanese-style sauna bathing that is known as Totonou is unique to Japan. Even though the sauna culture was brought from Finland, it has developed in its own way over here. Sauna is very popular in Japan now, with 12 million people taking it once a month, and 2.5 million people taking it a few times a week. It has become part of our culture now. The way we do is to have a sauna with about 90 degrees centigrade, for 6 to 12 minutes, then have a cold bath with about 16 degrees centigrade for 1 to 3 minutes, and finally, fresh air bathing for 10 to 15 minutes.
In Finland, they don’t have a cold bath, they have an ice bath in the lake. Many people in the United States seem to do sauna and ice bath cycling, or if it isn’t an ice bath, the temperature is still low under 10 degrees centigrade.
This temperature difference is critical. According to Dr. Yasutaka Kato, the author of Isha ga Oshieru Sauna no Kyokasho, A Textbook of Sauna by a Doctor, between 16 degrees and 17 degrees centigrade is the appropriate temperature for a cold bath. If it is below 15 degrees, we feel pain and above 17 degrees, it is not stressful enough. Therefore 16 to 17 is the sweet spot. Through a sauna and a cold bath, we activate the sympathetic nervous system, and through fresh air bathing, we activate the parasympathetic nervous system.
It is said that the hermetic effects of cold plunge and sauna are nearly the same, so you can replace the cold plunge with sauna.
I personally find the sauna is a lot more enjoyable. I think it is more doable for people over 50. When I watch videos of people doing cold plunge, many of them are quite young, but when you reach a certain age, you don’t have the same level of physical flexibility and mentality to challenge endurance.
I think the reason why the milder sauna style was developed in Japan has something to do with our mentality. Japanese people are generally cautious and we make sure things are safe enough. We can be tough in the case of martial art training and Shugendo practices. In Karate training, for example, they do Kangeiko in winter, which is to practice while standing in the water in the sea. But in modern-day sports culture, we take safety measures carefully. We always do stretching before exercises or even swimming in the sea. We don’t jump into the water right away.
For young people, maybe we are not fun enough-haha, but for seniors, this degree of cautiousness is safer.
I have not done the Wim Hoff method, so I can’t speak for it. If you do the proper breathing exercises and gradually train yourself to stay in an ice bath for over 10 minutes, you might get better effects and it seems to be a wonderful way to train your mind. Just like firewalking, it might give you the confidence to do anything in your life. Yes, you are going beyond your comfort zone while the sauna is still within your comfort zone.
So, it depends on what you want to accomplish from it.
If you want to biohack in a way to be superhuman, the cold plunge might be good for you. But make sure that you do it under the guidance of instructors.
For longevity and staying sick-free in general, and if you are over 50, I don’t think you need to do this far. It can be replaced with a sauna and cold bath cycling, hot bath and cold bath cycling, or even hot shower and cold shower cycling.
To do them, you don’t need to train yourself to be able to do them.
Even for those hormetic activities, you don’t need to do them, if you are already doing intermittent fasting and regular exercises such as Nordic walking and bodyweight HIIT. Sauna-related activities are optional if you can’t do other methods.
When you see people doing everything in their YouTube videos, you might feel that you, too, have to do them, but including myself, people who promote biohacking lifestyles do them for their work. We have to try everything to share with others about them, plus we tend to be fitness freaks who enjoy trying all kinds of methods out there. That is why we chose this line of work in the first place.
You just find your style, that is easy enough for you. The most important thing is that you enjoy doing it. Biohacking should be fun and doable.
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