Whistle Breathing also called storm breathing
Normally people whistle when they are happy, not so much when they are sad. A bit like singing, whistling is an action that calms, as sounds are expelled. The sound of whistle-breathing that I practice, is low pitch, a bit like a storm sound. The storm is happening outside of the body and it is as if the storm is observed from the calmness of the inside. A bit like watching a storm through a window from a safe indoor location.
There are two basic ways to exercise Whistle Breathing. One is whistling on the inhale by drawing air through a small hole formed with the lips and exhaling through the nose. Another option, is inhaling through the nose and exhaling through the mouth while forming a small hole with the lips.
Whistling while exhaling, works out better for me.