This method is something I stumbled upon accidentally while trying to loosen up during training. I spoke to Mr. Chan about this and he told me to be careful not to allow my head to wobble as this could injure the nervous system. I spoke to him about some of my experiences while doing it and my concerns. When I spoke to him regarding this he told me “don’t worry if you feel that Qi leaving as it will draw in more Qi “. Dr . Xie Pei Qi , a high level Yin Style Baguazhang Practitioner did Shaking Gong between the various Qi cultivating exercises . i have found it to be very useful in smoothing out the energy in the body as well as strengthening the bones and loosening the tissue . i always precede this exercise with Shuai Shou . i will shake 1 minute for every 5 Minutes that i have swayed . This is part of my daily training .