QIGONG means energy work or energy activity. According to the Chinese, the variation of Universe originated from the activities of five elements: wood generates fire; fire generates earth; earth generates metal, metal generates water element.
Also they suppress each other. Wood suppresses earth, earth conquers water then water suppress fire, fire suppress metal, (fire melt metal by heated) and metal suppress wood (metal cut wood).
The generative cycle is called mother & son relationship. And the suppress cycle is victor & vanquished relationship. The constant interaction produces the myriad phenomena of the universe. The five elements activity manifests themselves in the human body through their association with the five sets of paired organs, primarily the solid yin organs. The heart is ruled by fire, the liver by wood, the kidney by water, the spleen/pancreas by earth, and the lung by metal.