The Key to Internal is...

[taai gihk yahn]

as regards standing practice being the key to internal:

I personally believe that standing practice is of great benefit, for numerous reasons; based on my own study / practice, I see it, roughly, in 3 parts: awareness, balancing, transformation;

initially, standing is about building awareness of ur self - it teaches u about how ur weight is distributed (e.g. - more on one leg than another, more forward / backward on ur feet); how u align posturally in gravity (e.g. - do u overly accentuate ur spinal curves, or underexentuate them; do you displace ur thoracic cage over ur pelvis in alignment or not; is ur head too forward, etc.); where u hold tension inappropriately; and what the state of ur breath is; as a relatively static practice, it provides an opportunity to notice all of these things in a situation where there is a relatively decreased amount of afferent sensory input occurring, which enable u to pay attention to the things above more readily than if u were moving, even slowly like in a taiji form; it also helps u notice the manner in which ur mind functions - how thoughts enter and how u attach to them, how u loose ur immediate awareness of the above things;

after a while, things can begin to happen, which is the rebalancing phase: one of the main things that can occur is spontaneous movement; of this there r several types / qualities: people can experience shaking, swaying, or writhing types of movement; this can be due to both spontaneous muscular movement as the generator (also known as ideomotor activity), or other things - for example, when loaded in a certain manner over time, connective tissue can star to spontaneously "unwind", which means that the tension / compression oads in the CT will "cue" the muscular system to move in such a way that the CT tensions will start to work themselves out; this sort of movement can actually be extremely beneficial if one understands how to respond to it in context of standing practice - sometimes one needs to just "go with the flow", other times, one needs to actually concertedly maintain standing in relative neutral; over time, one changes the way one relates to gravity and the ground through the structure; also, one can experience various sorts of emotional changes during practice - things from the past can "come up" and one can have a wide range of feelings, sometimes swinging from one extreme to another - at this point, having a teacher who has gone through this phase is helpful; it is also at this point that the Taoist classics talk about spontaneous manifestation of sights and sounds, and how one should not get distracted by these phenommena; basically, if we r talking about a neuromusculoskeletal rebalancing, the neural part can result in stimulation of various visual / auditory cortices, resulting in the above mentioned manifestations; finally, one can experience various changes in the breath, where one can experience a wide range of breathing patterns that seem to change of their own accord without rhyme or reason; these and other things sign like temperature changes, r signs of the autonomic nervous system is rebalancing, or more specifically, moving from a chronic sympathetic to a more parasympathetic state (which is the phase within which tissue regeneration - healing - takes place); over time, the CT will also change, as fibroblasts start laying down new CT fibers in context of the improved alignment as opposed to aberrant force vectors that had previoully been sitting in the CT system, creating conflict and dysfunction;

the next stage, transformation, is what happens when one has a) full awareness of body / breath / mind and b) the various physical / emotional dysfunctions present in the system have been re-integrated to the degree that they no longer create undue strain on the system's ability to maintain a balanced autonomic system, and the drive towards homeostasis is optimized; this is the point where standing practice becomes transformative - where one can stand and instantly achieve integrated function of the breath and the postural system relative to the ground reaction force coming up from the earth through the legs, pelvis, spine and cranium - it's where u get that instantaneous feeling of being energized, a feeling of seemingly endless spaciousness throughout the joints and CT system, where the cranium seems to "bob" or be buoyant on top of the spine - at this point, one experiences a sense of global freedom, as well as manifestation of the so-called channels "opening" (it is at this pint that one completes the Orbital Circulations as well)

of course, all of the above is described classically in various Taoist treatises - it's just not delineated so explicitly, and of course much of the language is metaphorical, because at the time there was less understanding of human anatomy and physiology than there is now - nevertheless, the practice can be fully and validly articulated from a contemporary standpoint, which is useful in terms of contextualizing the practice for modern-day practitioners, as well as for doing away with the mysticism aspect that many people use to obfuscate rather than to reveal the simple, yet profound nature of something like standing practice

of course, there is much more: u can do all of the above lying down, sitting, or walking as well -(it's just slightly different in each case); then one can engage in various other practices, some alone, some w a partner to progress and refine this - these drils can b martial or nonmartial in nature;

finally, one can work with / teach others, which requires one to have a whole different level of understanding, especially if one is teaching this to people with clinical issues (which, as a PT, I have had much occasion to do, and have seen uniformly positive results in people with long standing histories of various dysfunctions;

but anyway, just my 2 cents based on my experience of standing practice...

addendum: this is the original topic of this thread, right? I mean, no one can accuse me of going OT now, right? of course, if anyone wants to say I know nothing about internal, and I'm sure they will , fine; but if they want to discount what I say, I hope that they will go through my post point by point and key specifically what is wrong and why - I invite anyone to do that and will be happy to dialogue about specifics; but if people insist on just dismissing broadly what i say without addressing specifics, that's just going to get them called out as a troll