Hey once3800, just a couple of comments about shamanic breathing. I don’t know where you’ve come across this, but I do know that some contemporary neo-shamanic practitioners (some with a decidedly “new age” flavor) are promoting this. Many neo-shamanic practitioners combine a little shamanism with a little of this and that from other traditions, and “brand” their potpourri practice then with new terms. While there may be some value in what they offer, such branding can be misleading.
While there are commonalities in the practice of shamanism throughout the world, there are really almost as many shamanisms as there are cultures, and there is no single, specific “shamanic breathing” technique associated with shamanism, and no specific breathing technique that derives from any shamanic society (with perhaps one exception, which I’ll get to in a moment).
The breathing of individual shamans can vary considerably, from shaman to shaman, and also within an individual shaman’s session of work with a particular person/group. At certain periods, the shaman may be breathing very slowly, very deeply. This can reflect the depth of the trance state he or she is in. At other periods in a single healing session, the same shaman may be breathing very fast and hard, rhythmically or arrhythmically. This can reflect his or her state of arousal mentally and energetically; it can reflect his encounters with or union with or embodiment of a helping spirit. The point being, in general, shamans do not try to breathe in any particular way; rather, their state of consciousness and level of physiological and mental and energetic arousal is the causative factor in particular breathing patterns, or lack of pattern. (Which isn’t to say that there aren’t any individual shamans who do breathwork as a part of their preparatory discipline.)
As shamanism is not a religion (although it can be used as one’s primary spiritual path), but rather a particular set of knowledge and skills, it can and does co-exist throughout the world with the dominant religion of a region or culture. Thus, an indigenous shaman in Mexico, for example, may court and work with the saints/spirits of Catholicism, along with various elemental, plant, animal, ancestral, or other spirits common to his or her indigenous worldview. A shaman in or near Tibet may work with Buddhist deities/spirits. A Native American shaman may include the spirits of Christianity in their work. This is in fact more common than any “pure” shamanism yet alive in the world today.
So, to that “exception” I mentioned at the beginning–in India and around Tibet, ancient shamanic practice can be interwoven with disciplines from the yoga traditions, particularly Tantra. There are breathing techniques (pranayama, or breath control) common to classical yoga. So a shaman in those areas may incorporate this type of breathwork or pranayama into his or her own disciplines (as well as other forms of yoga, such as hatha yoga). These may include things you’ve perhaps heard of from kundalini yoga, like the “breath of fire,” as well as rarer techniques. It may include holding the breath for extended periods of time, which can create what is know as tapas, inner heat or “mystical heat.”
So some of the references to shamanic breathing you’re hearing about may include some of these pranayama practices, or just general work with the breath to slow and deepen it, or quicken and “harden” it. And as I say, there may be value in what some neo-shamanic practitioners are offering when they include breathwork, but it is a bit misleading to refer to it as ‘shamanic breathing.’ And as for shadow, I would venture a guess that most authentic indigenous shamans have never even heard of ‘shadow.’ (Which, I repeat, doesn’t mean that a contemporary Western neo-shamanic practitioner here and there hasn’t created their own method of combining breath and shadow work with particular shamanic practices to some avail, and maybe if you do try it, you can let us know the results!)