Prana is a sanskrit word containing two syllables to make it's definition, 'pra' and 'an' which is it's root word. 'An' means movement and 'pra' is a prefix meaning constant. Prana means constant motion or life force; an invisible energy that fuels the subtle body. Since the moment our mother's egg united with our father's sperm, we're in constant motion. Prana is at the helm of energy that exists within you as the infinite source of matter from which you were born and sustained.
When I think of prana, it has a quality to it beyond the breath. This quality reminds me that it has different levels of energy. Some things take my prana, while others actually heighten it to a place of physical awakening.
Do you ever notice how you breathe? Not just in general. In situations when it's the most difficult to stop and pause to notice? Here is a thought; what if we have a pranic field just like there are other fields of energy? What if prana was a physical substance? What if you have a physical reaction by not supplying your brain with a constant moving flow of prana? These thoughts are rooted in the yogic or vedic tradition and have been with us since the upanishads.
Stop and notice your breath when you're feeling something that makes you angry or brings up an emotion that is hard to deal with. Notice what physical reactions are happening in your hands, yes, your hands. Notice your face, your neck, your shoulders. Notice what is happening to your body.
When we don't give ourselves the time to stop and notice, we create wave like patterns in our mind that disrupt our thought patterns. We become restless in our minds and this effects our energy field.