As was talked above, "sword energy" means the produced inner and exterior energy by practising Neigong and fist rule exercises is exerted on "sword rule".

前已述及，“剑劲”就是通过内功和拳法的练习所得到的内外劲力在“剑法”上的运用。

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Theoretical part: Classics such as: "The Liuhe classic", "Nine thesis", "7 fists and 14 parts - usage methods", "Neigong Si Jing", "Xi Sui Jing", "Yi Jin Jing", "Quanshu Yun Yi" and others.

理论部分：古谱《六合拳谱》、《拾法摘要》、《九要论》、《七拳十四处用法》、《内功四经》、《易筋经》、《洗髓经》、《拳术运义》、《宋氏形意拳及续编》等。

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