Tao yin (sometimes referred to as Taoist yoga) is a series of exercises (mainly in lying and sitting positions, but also in standing positions) practiced by Taoists to cultivate ch'i, the internal energy of the body according to Traditional Chinese Medicine. The practice of Tao Yin was a precursor of qigong, and was practised in Chinese Taoist monasteries for health and spiritual cultivation. Tao Yin, is also said to be a primary formative ingredient in the well-known "soft style" Chinese martial art, T'ai Chi Ch'uan.