“KuaKneeOpen-Chen Zhonghua Online Lesson 20210826” Online Video Purchase
Presenter: Chen Zhonghua Length: 1 mins Difficulty: 3/5 Language: English  
Year: 2021 Location: Edmonton, Canada
Kua and the knee are related to each other. When we open the Kua, the knee must be locked, otherwise you are tossing and moving from one place to another.
If your torso is not fixed in one location, you are tossing.
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"Chen Zhonghua Online Lesson 20210826" Online Video Purchase