Yijin Jing
The Yijin Jing (simplified Chinese: 易筋经; traditional Chinese: 易筋經; pinyin: Yìjīn Jīng; Wade–Giles: I Chin Ching; lit. 'Muscle/Tendon Change Classic', 'or "Sinews Transformation's Classic"') or Yik-kan Ging (Yick Kan Ging) is a manual of Daoyin exercises, a series of mental and bodily exercises to cultivate jing (essence) and direct and refine qi, the internal energy of the body according to traditional Chinese medicine.