jack wrote:hello every one. During grasp birds tail practice, we generally put one leg at front and second to the behind. How should we keep the 'leg behind'? i.e. straight or slightly bent from the knee?
As a general rule for the Yang style tai ji, all the arms and legs should not be extended all the way to maintain balance. In this case, if the leg behind was straight, then the body tends to lean forward which causes the center to be shifted. It is vulnerable to move forward by someone who gives a pull or push. However, if the leg behind was slightly bent, then, the body would have more control to counteract the pull or push. Same thing goes to the leg while standing, it's better to have the leg bent to act like a robot arm with two pivot points, like the ankle and knee. Hence, the body has more flexibility to move in any direction.
There is an old classic saying for the Yang style:
曲中求直: Desire to be straighten from a bent position
直中求曲: Desire to be bent from a straight position
These saying applies to both the arms and legs. It sounds paradoxical but it puts an arm or leg in a dynamic mode.
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