Characteristics
The reason for the label "internal," according to most schools, is that there is a focus on the internal aspects earlier in the training, once these internal relationships are apprehended (the theory goes) they are then applied to the external applications of the styles in question.
External styles (外家, pinyin: wàijiā; literally "external family") are characterized by fast and explosive movements and a focus on physical strength and agility. External styles include both the traditional styles focusing on application and fighting, as well as the modern styles adapted for competition and exercise. Examples of external styles are Shaolinquan, with its direct explosive attacks and many Wushu forms that have spectacular aerial techniques. External styles begin with a training focus on muscular power, speed and application, and generally integrate their qigong aspects in advanced training, after their desired "hard" physical level has been reached.
Some say that there is no differentiation between the so-called internal and external systems of the Chinese martial arts, while other well known teachers have expressed differing opinions. For example, the Taijiquan teacher Wu Jianquan:
Those who practice Shaolinquan leap about with strength and force; people not proficient at this kind of training soon lose their breath and are exhausted. Taijiquan is unlike this. Strive for quiescence of body, mind and intention.
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