>>41104183
Wim Hof breathing is a version of a legit yogic technique (Bhastrika Kumbhaka), but I would never recommend it to beginners. To understand why, you need to understand some subtle anatomy as well as what we are trying to achieve here.

Essentially, there exists a strong energy in all humans, in the region of the perineum. The yogis call this Kundalini, lying dormant in the Muladhara-Chakra. The daoists call this point Hui Yin, which stores the Jing (Essence) of a person. We want this energy to flow freely through the spine. In yogic terms, we want Prana (energy) to flow in the Sushumna (central channel). In daoist terms, we want Qi (energy) to flow in Du Mai (governing channel). It is all the same thing.

So why does the energy not flow? Because it is blocked. Most people are blocked up in some way, some more than others. But there is even some structure to blockages. Old yoga texts talk of three Granthis (knots) along the Sushumna. Daoist texts talk of San Guan (three barriers) along the Du Mai. These main blockages are at the base of the spine, middle of the spine and at the top where the skull connects. To overcome these barriers, there are two steps.

First, weaken the blockage through correct skeletal alignment, relaxation, and purification techniques. TRE is essentially one of the most potent purification techniques.

Second, increase the energetic pressure through semen retention, breathing techniques (for example Wim Hof method), and body locks (for example Mula-Bandha, contracting the Anus).

Raising the pressure without weakening the blockage first will just be a waste of your time, in the worst case you will actually manage to bring energy up and fry your nervous system which is not ready. My recommendation would be to just focus on purification first. You will experience energy flow just doing that as >>41102854 described. If you want to add a breathing technique, I would recommend abdominal breathing from daoist tradition.