The word qi or chi may be short, but boy it's got a lot of energy. In fact, qi stands for the energy that lives in everything. It translates into Life Energy or Life Force.
In many Asian cultures, Qi, also spelled chi or ch’i, is the life force that every person and thing has. Traditional Chinese medicine and acupuncture both address the concept of Qi; if you’re feeling a little under the weather, an unbalanced qi may be the culprit. Martial arts also use the concept: if you’ve ever practiced tai chi, then you’re already familiar with qi, just with a different spelling.
The Huangdi Neijing ("The Yellow Emperor's Classic of Medicine", circa 2nd century BCE) is historically credited with first establishing the pathways, called meridians, through which Qi circulates in the human body.
In traditional Chinese medicine, various illnesses are believed to be either the product of disrupted, blocked, and unbalanced qi movement through meridians or deficiencies and imbalances of Qi. So in Traditional Chinese medicine often seeks to relieve these imbalances by adjusting the circulation of qi using a variety of techniques including herbology, food therapy, physical exercise including QiGong, Taichi, and other martial arts training.
If you are ever curious about how your Qi or feeling under the weather you can check in with your local Traditional Chinese Herbalist, Qigong master, or Licensed Acupuncturist for a check up and tune up. Like all things in the East Healing system, health and well being is accumulative, not an all or nothing game. Start with small changes, but do them consistently. Over time they'll have big impacts!