Our breath is our life. Without breath, we are not alive.
Breath, and breathing, has been used for thousands of years as a tool for healing, for calming, for gaining deeper understanding of the self.
Just a simple 4-7-8 pattern (breathe in for 4 counts, hold for 7 and breathe out for 8 counts) done a few times can help anyone calm their system, not just their mind. When we breathe deeply, evenly and slowly, we literally calm the vagus nerve that runs from parts of our ears to the top of our femur or thighs.
And, once we establish a pattern of breathing that is shallow and fast, not calming, our body makes that way of breathing a habit. Especially when we are upset or tired or overwhelmed. Sad. Angry. Resentful. A habit.
The good news about habits is that you can change a habit. With a little attention and time you can learn to breathe deeply and slowly...consciously. And the body, because it 'likes' calm, is happy to go along with this new way and pretty quickly adapts. And the easier, calmer way of breathing becomes a habit.
And don't forget, when you change a habit it is not only your body that is benefitting, the brain also changes. This is a practice!
Here is the Youtube video of Dr. Weir demonstrating this method: www.youtube.com/watch?v=YRPh_GaiL8s