If you click on the link, you will be directed to an artice entitled "Learning the Internal Dynamics of Tai Chi" by E. Marie Koepsell. It appeared in Tai Chi Magazine in August of 1998. I've included a portion below. Ms. Koepsell's teacher is Dr. Stephen Hwa, who teaches Classical Tai Chi. Please pay his site a visit. His lineage is certainly interesting. His teacher was Yang WaBu, who lived to be over 100 years old! Mr Yang was a direct student of Wu Chien Chuan, who is considered the founder of the Wu style of Tai chi Chuan. Wu Chien Chuan and his father Wu Chuan Yu were both Imperial Bodyguards who learned their Tai Chi Chuan from the celebrated Yang Lu Chan and his sons. The link was brought to my attention by Mr. Jim Roach, Dr. Hwa's senior student. There are some additional interesting things to be found at Mr Roach's site so please pay him a visit as well. Here is an excerpt from that article:
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"The internal physical discipline of T'ai Chi Ch'uan" according to Dr. Hwa, 'involves the intensive training of the body and mind to develop discipline in movements so that the movements originate from the abdomen (dantien) and hack, in addition. the energy flow of these movements are developed in a relaxed body, giving an appearance of effortlessness:'
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As we start aging,” according to Dr. Hwa "less and less of our movements came from the waist and back. We hold our middle stiffly, and more of our movements originate from the shoulders and the hip joints. This puts pressure on joints and we lose strength and mobility. Ultimately, we may stop using these area, of our bodies altogether. Atrophy sets in, creating the major problems of aging.”
He demonstrates this by having students raise their arms to shoulder height and push forward He noted that most people lift and push from the shoulder joint and arm muscle. and there is little strength involved. He demonstrated the way he pushes, using his back and abdominal muscles with the shoulder and arm completely relaxed- Similarly, When he moved his arm, across his head, his back and abdomen did the work.
Dr. Hwa similarly feels that T'ai Chi steps should involve the muscles of the torso, the large abdominal and pelvic girdle muscles, to lift and push the leg farad and hack. He said the leg muscles are used to move the body forward and backward. but the muscles of the torso do the work of lifting and positioning the leg, and planting the foot. The weight sifts after the leading foot is planted solidly on the ground, whether it is going forward or backward.
Turning movements of the body, according to Dr. Hua. are done with the feet stationary and the body swivelling at the waist He said it should not he a twisting motion where the hips or legs turn the body. but rather an abdominal movement. When he demonstrates !he movement. his lower and upper abdominal muscles appear to rotate in opposite directions, indicating all the power that this movement generates at the waist:
"The unifying principle of the internal physical aspect of T'ai Chi is that all movement and physical energy originate at the waist and back, the strongest parts of the body and its center of gravity." Dr. Hwa said.
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"The first goal for the T'ai Chi practitiioner is to have the qi circulate continuously throughout the body, following the Yin/Yang changes of the movements. To achieve the Yin -Yang balance of the body and mind It is essential that these movements of intense energy and stretching be performed in an otherwise relaxed body and mind.
"The practitioner must not only be aware of the Yin/Yang of individual movements, but also the total Yin/Yang of the body as one goes from movement to movement," Dr. Hwa said.
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I have taken only a few steps on the path of learning, but I am amazed by the richness of the art. My prior T'ai Chi exposure was enveloped in a philosophical and abstract context. But now I see that T'ai Chi can be explained in scientific, concrete terms and it is no longer such a mystery to me. I have developed even more respect and admiration for the art. Unquestionably, the internal physical discipline, with its power to bring out the inherent potential in a person, has been, for me, a most significant discovery.