Why practice Qi Gong? For one thing, it's an alternative to the gym, and it's effects are similar to an acupuncture treatment.
Qi gong is a low impact but powerful exercise that nourishes from within. It helps promote the free flow of qi, alleviating physical symptoms and emotional imbalances. It also helps maintain good health.
In Chinese Medicine there is a saying: "Qi is the commander of Blood, Where Qi goes the Blood must follow. Blood is the mother of Qi." Qi is like a current in a river; it carries everything in it's flow.
Simply, a healthy qi flow equals complete circulation of blood throughout the body, delivering nutrients and oxygen, stabilizing hormones, and removing metabolic waste.
Master Li's qi gong practices are my favorite. Fun fact: Master Li starred and choreographed martial arts films in China before devoting himself to the more peaceful practice of Qi Gong. Try practicing it below and see how you feel. You can order his DVDs from the Shen Zhen Society website: http://www.shengzhen.org/