Today, my son and I went to the upper stream of Echi River in Oku-Eigenji for a swim. Here, water was much colder than that of lake Biwa, so it has a further benefit as bio-hacking. There are three benefits of river swimming as Shizenha Bio-Hacking.
1, Hormesis Effect
As I mentioned in my post about Takigyo, river swimming can have the same effect as Takigyo, being under a waterfall.
If you swim at upstream of a river, usually water is cold and when you are in cold water for longer than a minute or so, you create a kind of hormesis effect. According to David Sinclair, exposing yourself to cold temperatures for a certain period can stimulate longevity gene sirtuin. If you do it on a hot summer day, you can alternate between being in cold water and being under the scorching sun. It is like having a sauna and cold bath back and forth.
2, Swimming HIIT
Swimming itself is great cardio and muscular exercise. You can even do HIIT with it. You swim for 20 seconds, rest for 10 seconds, and do that for 8 sets, it becomes HIIT.
River swimming is a wonderful way of doing earthing. You are walking on stones with your bare feet. You can find a big rock and stand on it, too. Being in the stream, you are part of nature.
The Ikigai Diet: The Secret Japanese Diet to Health and Longevity