Yang and Yin Tissues
There are yang tissues and yin tissues in the body. Muscle is a yang like tissue that prefers dynamic and rhythmic movements that exert a repetitive stress. For example a weightlifter might do bicep curls with a dumbbell for 3 sets of 10 repetitions as a way to make the muscle stronger. Connective tissue is yin and responds well to a long, slow and soft stretch.