Qi is a generic term for energy. For example, the air we breath is called kongqi 空气, which translates literally as empty energy. The process of breathing is controlled by our autonomic nervous system. This means we do not have to consciously in hale and exhale, but the the respiratory system appropriately regulates itself automatically in response to our physical and emotional states. Although we can explore ways to improve how to breath more effectively, it is best not to intentionally regulate forcing naturally long breaths to shorten and naturally short breath to lengthen. A little knowledge can be a dangerous thing. Many practitioners implement regulated breathing practices without doing a deep enough study. Considering how vital breathing is compared to hydration and nutrition in the production of the body's intrinsic energy, it is best to keep it simple. Make sure when exercising to avoid holding the breath. Many student don't realize how easy this is to do, while attempting a rather challenging movement like kicking or Snake Creeps Down. Where breathing is autonomic, directing the body precisely following memorized choreography is controlled using the somatic nervous system. We consciously make the body move using the information stored in the mind. Yang Jun, Laoshi advises us to keep the mind in the body. Furthermore by doing this mindfully, we can work with the gross and subtle feedback we receive from the sense of touch (feeling)from the rising and falling sensations in the body. Natural deep breathing can help us relax. Forced breathing trying to expand the abdomen is not the point. When the diaphragm is given sufficient room to descend further into the torso by relaxing the abdomen the belly naturally expands as the lower lobes of the lungs fill. Tai Chi Chuan is a return to our natural physical and mental state that unfortunately we may have lost due to misuse or neglect. Progress requires a lot of patient consistent practice; not merely seeking to improve by amplifying strengths, but more importantly, seeking to identify mental misconceptions and physical flaws. Learning is constant change. We don't simple keep doing the same thing over and over expecting a better result. Image: Trees live off the carbon we exhale. We live off the oxygen they give off. It is a symbiotic relationship. I have heard there is just as much tree below grown as there is above. Like us, they exist between Heaven and Earth. To me, a tree's branches and stems resembles the bronchial tubes of the human lung. What the trees breaths in pure or dirty, ultimately we breath in too. Taking care of the Earth is taking care of ourselves. We should all strive to leave behind a world better than we found it.