Healthy tendons are the foundation of true strength in the body. Strong and supple tendons and open joints allow more space to store raw energy, which can then be transformed into higher creative and spiritual energy. The eight postures of Tendon Nei Kung are specifically designed to open the joints and fortify and grow all the tendons in the body, strengthening them as a unit. Like the practice of Iron Shirt Chi Kung, Tendon Nei Kung cultivates the ability to move the earth force up from the ground, through the feet, and into the body, in this case raising it to nourish the tendons. In Tendon Nei Kung, Mantak Chia explains how to perform the eight postures individually as well as with a partner. He reveals how regular practice of Tendon Nei Kung can help prevent and relieve arthritis by forcing poisoning acid out of the body to make room for healing chi energy. He provides ten supplementary exercises to help heal damaged tendons and joints without strenuous movement and also includes information on the Mung Bean Hitting practice, an ancient practice that in addition to repairing damaged tendons and joints also aids in detoxification and relieves constipation, stomach cramps, and headaches.