The actions of inhalation and exhalation activate the nervous system in different ways. The inhaling breath activates the sympathetic. It feeds the body with oxygen and has an invigorating and energizing effect. Positive emotions related to the sympathetic nervous system are excitement, enthusiasm, wakefulness, and activity. Too much sympathetic activation leads to stress, agitation, and anxiety.
The exhalation is releasing and calming. It activates a parasympathetic response. Positive emotions linked to the parasympathetic nervous system are relaxation, peacefulness, contentment, and ease. That is why we benefit from focusing on our exhalation when we feel stressed or anxious. A healthy nervous system effortlessly moves between sympathetic and parasympathetic activation as a response to its environment. Only an unbalanced nervous system gets stuck on ‘on’ or ‘off’. A nervous system that has frozen into ‘off’ mode results in fatigue, sluggishness, apathy, and other tamasic symptoms. This is the case for the typical type of depression. More invigorating breathing exercises, and exercises that emphasize inhalation, can help to reduce lethargy and increase feelings of aliveness.