The breath seems to be a mechanism that links the unconscious and conscious systems. It is one of the foundational self-regulating mechanisms for the nervous system.
You can speed up breathing to increase arousal or slow it down to elicit relaxation.
Similarly, longer more pronounced inhales followed by shorter exhales creates an “up-regulating” effect whereas shorter inhales followed by longer more pronounced exhales creates a “down-regulating” effect.
Consider trying each of those practices to notice the effects.
If you seek to increase alertness, try rapid breathing with pronounced inhalations.
If you seek to increase relaxation, try slower breathing with pronounced exhalations.
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