Friend of the Notebook, Byron Jacobs, who lives in Beijing, recently posted a video giving a glimpse into the martial arts culture found in Beijing parks. You can see people doing all sorts of martial practices, like calisthenics, chi kung, Tai Chi, sword and push hands.
Byron comments:
“Beijing’s public spaces and parks have been gathering places for people from all walks of life for generations. This includes martial artists, who would meet regularly at such places to practice as part of their general lifestyle. Throughout the many parks of the capital, you can find practitioners of various styles and standards getting together to train regularly. This is a glimpse of some of these special places. The first episode features the Temple of Heaven.”
One admonition from Yang Cheng Fu’s 10 important points, that has become something of a law in Tai Chi Chuan, is to ‘keep the head suspended, as if from above’. In the Tai Chi Classics it also states “Stand like a perfectly balanced scale and move like a turning wheel”, whilst also saying, “Don’t lean in any direction; suddenly appear, suddenly disappear.”
These quotes have produced all sorts of controversies in the Yang style side of the Tai Chi universe. If you look at ChengFu’s student Cheng ManChing, who did so much to popularise Tai Chi in the West, you can see that he changed his form to truly embody this principle of suspending the head and standing like a perfectly balanced scale. In a forward posture, Cheng ManChing kept his head, neck and back vertical in relation to the ground at all times. He allowed no forward incline at all. To stay vertical he softened his back knee a bit, which removed the straight line from the heel to the head, producing a much softer posture than his teacher, Yang Cheng-Fu, exhibited.
Whereas, if you look at pictures of Yang Cheng-Fu in a similar forward posture you can clearly see that he holds his head in the same vertical alignment, but holds his back with a slight forward incline. He keeps his back leg straighter, forming a straight line from his back heel to his head, meaning that his posture is slightly harder than Cheng ManChings, and he exerts more of a forward pressure.
Both of these approaches can be seen as interpreting the advice to not “lean in any direction” differently. The situation becomes even more confusing when you look at the Wu style of Tai Chi Chuan, derived from the version of the form practiced by ChengFu’s peer Wu Jianquan. Wu holds an even more inclined position, which keeps the head vertical, but often seems to break the line at the hip, so that the back heel is no longer in a straight line all the way to the head. Being of Manchu heritage, Wu Jianquan had a shuai-jiao background. He was taught martial arts by his father who was a student of Yang LuChan and also a cavalry officer and imperial palace guard, as he was, so a change in his preference for grappling techniques could very well account for the changes in his version of the form.
I used to ponder these discrepancies a lot, but these days I have become more interested in the relation of the back (including the neck) to the hands and arms, regardless of its orientation in the vertical plane. When we lift and use our arms our tendency is to bend the top of our spine and drop the head forwards, a fact that can be proved each and every time you type on a laptop. The next time you’re sitting at a laptop observe what happens when you start to type. Notice that your head wants to move towards your focus of attention, the object you are interacting with.
Recently I was watching an excellent performance by a child doing Bak Sing Choy Li Fut, filmed in the 1960s. Young children doing martial arts can be great teachers because they effortlessly keep their posture as they move. It is only as we become adults that we seem to lose this ability.
Search for the video “Old Kung Fu Footage in Hong Kong in the 1960’s” on YouTube and you’ll see what I mean. Watch the good posture he keeps throughout – his back remains still in relation to the movement of his arms allowing his neck to stay extended and space and awareness to be present.
This is what I think is being asked for in Yang Cheng-Fu’s writings and the Tai Chi Classics, not mere fussing about how vertical a posture is. What is required is the freedom to move our arms, but to keep our back still, and maintain our head and neck relationship without falling into the trap of bending towards the object of our attention.
But how do we train this? Here’s something simple you can try. Get a 4-pint carton of milk out of the fridge and swing it in a figure of 8 in front of you. Now do it again and notice how you head wants to be pulled forward. Resist the pull and feel the work done by the neck and back muscles to prevent it from happening. It shouldn’t feel like they’re straining, but they should feel active.
You can do the same thing with a heavy sword, of course, if you want to look more like a traditional martial artist, and less like a deranged milk man. And once you get a feeling for it you can try it without a heavy object, in which case it becomes more like a silk reeling exercise, or you can try and keep the same feeling when you do the Tai Chi form. In which case it doesn’t look like anything.
Obviously, when you are standing still, or sitting, in meditation you can achieve the same relationship of the torso, neck, head and arms but with even less use of muscle to maintain the position. Initially at least. If you try standing in a Zhan Zhuang posture with your arms extended for a few minutes you’ll start to feel your neck and shoulder muscles tighten. This is where you need to work on relaxing them, yet maintaining your posture. You need to let the weight of the upper body rest on the lower body, and flow down into the ground through the centre of the foot, or through the sitting bones if you are seated.
A human head is quite heavy, at around 5KG, which is a lot more than a typical bowling ball weighs. If the head moves forward of the hips too far then we have to start using a lot of muscle to hold it up. In a way, the neck being tense, or feeling tired, after we’ve been doing an activity is a warning sign that we’re not using our body to the best of our ability. If we can maintain the relaxed, neutral, position of the neck through movement, then the weight of the head is transfered down to the ground through our frame instead. Our breathing will be better, and we won’t lose that sense of lightness and ease that the kid in the Choy Li Fut video from the 1960s so effortlessly demonstrates.
Finally, his idea of keeping an open relationship between the head, neck, back and arms raises a few good questions when applied to martial arts. What springs first to my mind is, should you have your head in that position to fight? I’d say probably not – you want to tuck your chin in a bit more when you fight, for obvious reasons, but the real question is how you tuck your chin. The idea of the extended neck that you’re training by working on your posture can be transferred into the way you tuck your chin. Dropping the head towards the opponent has all the same disadvantages we’ve outlined above when applied to martial arts, and will inhibit the free movement of your arms, so critical to fluid punching, not to mention making you more hittable.
So, keep your head up, as people say to you when you’re looking down. Walk lightly, smile brightly!
Here’s a nice video of a Xing Yi Quan linking form showing some really nice Xing Yi Quan body methods.
Xing Yi Quan master Tian Jinglong (田景龙) shows Advanced and retreat linked form(Ji Tui Lianhuan（进退连环拳). Tian Jinglong is disciple of Li Jinbo(李金波), youngest student of legendary Hebei province warrior “Iron Luohan” Zhang Changfa (张长发aka Zhang Xiangzhai张祥斋) . Lineage: Li Luoneng(李洛能)—Liu Qilan(刘奇兰)—Liu Dianchen(刘殿琛)—Zhang Changfa(张长发)—Li Jinbo(李金波)—Tian Jinglong(田景龙)
Michael Rook posted about an online course in Hap Gar that’s starting in January, so I thought I’d check it out and had a go with one of the free videos as my morning workout. The teacher is David Rogers of Rising Crane, and the workout is a nice, not too heavy, way to start your day while learning some Kung Fu. Plus it’s free, so give it a go! I really enjoyed it. After a warm up you’ll work on the first 5 basic punches of Hop Gar and some stances.
Richard is a teacher of Tai Chi and Hap Gar Kung Fu through the Rising Crane. David only takes one or two student groups a year for online learning, and it’s a very interactive, personalised training session so a whole group can move through it together, getting feedback as they go.
I haven’t done Hap Gar before, but I’ve done a lot of Choy Lee Fut, and to my eyes there appears to be very little difference between the two. Hap Gar looks like a version of Choy Lee Fut to me, even the same names are used for the moves, so it was great to experience a Kung Fu style I was already familiar with, but from a slightly different perspective. I also liked his thoughts on fighting strategy for these long range styles that he gives at the end, around the 35 minute mark, plus I liked his thoughts on MMA.
That is one mean looking crane. Photo by Pixabay on Pexels.com
Today I want to talk about a very useful martial arts teaching called the 3 timings. In many ways, these teachings are the secret to all martial arts, so you’re getting some pretty good value out of this free blog post! 🙂
The three timings have been handed down in many different martial arts lineages under different guises, but it’s all the same teaching. I suspect the 3 timings are as old as time itself.
Personally, I’ve found the three timings most applicable to weapons work, but they are obviously important for barehand too.
The version of the 3 timings handed down in my Chinese lineage was called “Yi timing, Chi timing and Xing timing”, but in English you’ll find them explained perfectly well by Paul Vunak here as simply, before, during and after:
Paul Vunak is a Jeet Kune Do teacher. Bruce thought the concept of “Jeet” was so important he named his martial art after it. The “Jeet” in Jeet June Do means to intercept, and intercepting is what the 3 timings are all about.
The 3 timings is a pretty simple concept. You can hit somebody:
“After” they have completed their technique (xing timing), for which you obviously have to move out of the way before you respond. This is the slowest timing and easiest to perform.
“During” their attack (chi timing). This is a much shorter timing, and it could end up in a simultaneous strike where you both hit each other, but ideally you would just sneak in first and beat them to the punch.
And finally, “before” they strike you (yi timing). This is the hardest timing to achieve, because it’s very easy to get wrong. For true Yi timing you need to hit them before they launch their attack, but equally, their attack does need to be a genuine attack. If you fire on Yi timing (”intention” timing), and they are faking, or not attacking, you’ll end up out of position and vulnerable. Yi timing therefore requires immense practice and sensitivity so that you can accurately read the whole situation in the blink of an eye.
Timing is the ultimate skill in martial arts. If you are a master of timing, then you almost don’t need any technique. If we are both holding swords and I can always time my attack to hit you anytime you come towards me then I can forget about “Green Dragon Scoops the water” or whatever fancy technique I know. It all becomes irrelevant.
So how do you practice the 3 timings? Well, I’d suggest that the first stage would involve getting a partner, like Mr Vunak has done in that video, and practicing responding to set attacks, so you can develop a feel for each timing. Obviously this would need to be done predictably at the start then slowly more variation can be introduced and the sparring can become freer. Instead of the other person just feeding attacks, they can try to start to make their own attacks and counters.
If you practice barehand and with weapons then you’ll notice how much quicker the timing needs to be with weapons. You have so much less time to react. In fact, going back to barehand after using weapons you will almost feel like you are moving in slow motion, which is a handy skill to have for obvious reasons.
With the timings at the heart of your practice you might also change the way you think about moving in martial arts. Ways of moving that require a unity of body and mind become much more important. You need to move everything together, and as one, to hit your timings.
The words of the Xing Yi Classic of Unification become more important:
“When the upper and lower move, the centre will attack. When the centre moves, the upper and lower support, Internal and external, front and rear are combined, This is called “Threading into one”, This cannot be achieved through force or mimicry.”
Hundreds of years after these words were written, Bruce Lee came to the same conclusions, and based his new martial art around the concept of timing, naming it Jeet Kune Do, the way of the intercepting fist.
Time to address some more comments generated by my Whole body movement post. Oliver Gerets writes:
“The body can move/coordinate in an almost unlimited number of ways. These kind of oversimplified comparisons are useless and misleading. There is no general/right way of “whole body movement” in Taijiquan. Every school/lineage is at least slightly different. “
This is an interesting point. Are all the different styles of Tai Chi actually different martial art styles, or are they all one? The generally accepted wisdom on the matter (Chinese government-backed) is that (in theory) there is only one style of Tai Chi. But when you get on the ground, in amongst the weeds, then it’s really hard to see how somebody doing Sun style Tai Chi is doing the same thing as somebody doing Chen style, and how either of them are doing the same thing as somebody doing Yang style. Sure, if you follow the sequence of their long forms, they follow roughly the same order, but the stances are all different and the type of body movement looks different. They might have had the same starting point, but over the years, they seem to have diverged significantly.
Or have they? Let’s return again to the three principles I listed as the essence of Tai Chi whole body movement in my last post.
1) moving from the dantien 2) power up from the ground (jin) – rooted in the feet, expressed by the fingers. 3) coiling and spiraling actions from the dantien out to the extremities and back.
You can argue that these 3 things are happening in all Tai Chi styles.
Sun style.
Yang style
Chen style
But, the hard truth is that number 1 is not always observed in most practitioners, and number 3, is most often dropped entirely in the styles that don’t start with a letter C in their name.
Is that a bad thing? It’s point 2 that is the most important. Point 2 can be done without point 1 and 3 and you still have a functional martial art. Point 2 is also the thing I see that ties together all the “internal” arts in the most obvious way – Bagua, XingYi and Tai Chi Chuan.
We only have so many hours to train a week. I think you could make an argument that if you want to get anywhere in Tai Chi, then you’re better off spending most of your time working on point 2 anyway.
If you add in points 1 and 3 then you get even better movement. It’s a different type of movement. I think it’s worth investing time in learning points 1 and 3 as well, but make no mistake – it’s a significant investment of time. A good place to start is a simple single arm-waving silk reeling exercise:
Oliver’s final point is:
“There is no sense in moving like a cheetah, only if you want to run in a similar way. Which is not useful as a human being.”
It’s peculiar that he’s written this in a Facebook group (Ancestral Movement) which seems to enjoy looking at the way animals move and what we can learn from them. As mammals, our bodies really aren’t that different. Generally, we all have a spine, 4 limbs and a head.
I’m not suggesting that we should pretend to be a horse or a cheetah, but the principles of movement in mammals are shared amongst all species. Even us.
Here’s a review of an Ancestral Movement seminar, if you want to find out more about it.
I’ve been thinking of the way to describe what ‘whole body movement’ means in Tai Chi. The problem is describing a specific feeling, or body movement using words, which leaves the meaning open to interpretation and misunderstanding.
In Yang Cheng-Fu’s Ten Important Points, No. 7 says:
“7.) Coordinate the upper and lower parts of the body. The T’ai Chi Ch’uan Classics say “the motion should be rooted in the feet, released through the legs, controlled by the waist and manifested through the fingers.” Everything acts simultaneously. When the hand, waist and foot move together, the eyes follow. If one part doesn’t follow, the whole body is disordered.”
This is an expanded version of the more condensed and often heard phrase: “One part moves, all parts move”. But it’s also misleading.
If you take the line “Everything acts simultaneously” at its literal meaning you don’t have Tai Chi movement. You have robot dancing.
Now don’t get me wrong. I like robot dancing as much as the next Peter Crouch fan, but it’s not Tai Chi. When you see a performer doing the robot dance she often swivels the waist sideways, or dips the hip with the arm locked to the body. With the dip the whole torso and arms all move downwards together, simultaneously. Something like this:
It’s fairly obvious that this is not what is meant by Yang Cheng Fu when he says to move the body parts simultaneously, and yet I do see people falling into this trap quite often. They obviously had no intention to set out moving like a robot, but when the brain gets the idea that the body must move as a unit, the resultant expression can often end up far from the mark.
Instead, the way the body moves in Tai Chi should be more like ripples emanating from a stone dropped in a lake. The central point is the dantien. The waves begin there and ripple out to the extremities (feet, head and hands).
When you move, the dantien moves first, and the rest of the body follows in a coordinated action, almost as if dragged by the dantien. It is loose, connected, relaxed and powerful, rather than stiff, jerky and ’empty’.
The parts of the body don’t all move together at exactly the same time, otherwise you’ll end up like a robot. Instead, you want to be more like the way an animal moves. Animals demonstrate some of the best, most graceful, full-body, co-ordinated movement you’ll ever see.
The Cheetah is the classic one that’s used to illustrate open and close in the body, but also the directed head position. Just look at how the head helps with the coordination when running here:
While we run with a torso held in the vertical plane and the Cheetah runs with the torso in the horizontal plane, the head position remains key.
Point 1 of Yang Cheng-Fu’s 10 Important Points is:
1.) Head is held upright to let the shen rise to the top. Don’t use li, or the neck will be stiff and the chi and blood cannot flow through. It is necessary to have a natural and lively feeling. If the spirit cannot reach the headtop, it cannot raise.
In the Cheetah, the engine is the dantien area. The torso does big opening and closing movements as it sprints and the head points the way, keeping the spine flexible, but extended.
“All movements are motivated by Yi, not external form”,
I’ve talked a lot on this blog about things to do with the body in Tai Chi, but I’ve not really said much about the mind before. That’s because it’s a lot harder to talk about, since, as you’ll discover, the requirement for correct use of the mind in Tai Chi has nothing to do with “thinking”, which makes it especially hard to talk about because as soon as you verbalize or write down your thoughts you are, in effect, thinking about it. See the problem?
The classics use three words to describe the mind in Tai Chi:Shen, Xin and Yi.
We’ll leave Shen and Xin off the table for now, but the important point is that different words are being used to describe different aspects of the mind.
Let’s look at the big one: Yi.The Tai Chi classics are pretty unequivocal about the importance of Yi to Tai Chi:
“All movements are motivated by Yi,
not external form.”
But what is meant by Yi? The English translation given is usually “intention”. However, I think this is cause of more confusion about Tai Chi than anything else. People take it literally and think it’s the intention you have when performing the movements of Tai Chi – like the intention to grab and arm, or the intention to fight, or the intention to break a wrist, etc..
When people try to demonstrate this correct intention they simply pull a mean face and try to look a bit stern and aggressive while punching or doing something dramatic. That’s not it.
The word “intention” is definitely related to what Yi really is, but it’s not what is meant by Yi, not by a long way.
If you look at the face of somebody good performing Tai Chi they never look like they’re straining, aggressive or mean. Instead, they look like they are full of awareness, absorbed in what they’re doing, but open to their environment at the same time.
Yi has nothing to do with thinking, in the conventional sense at all. If you look at somebody doing Tai Chi who is thinking at the same time their movements look a bit empty, their eyes fidget all over the place, they are absorbed in themselves but not really ‘in’ their bodies. The mind and body have become separated.
In Tai Chi you want to achieve a unity of mind and body, so that there’s effectively no difference. You are just one unit doing the work, or rather, letting the work be done through you. You are present, but simultaneously aware.
I like to call Yi “directed mind”. It’s all about directions. When I’m performing the opening movement of Tai Chi for example, I am performing an opening of the body as the hands raise and a closing of the body as the hands fall. My mind is performing the directions up, in, down and forward in that order.I am directing where the body is going with my mind and eyes. Your eyes have to be working in harmony with the whole process, not distracted, or looking in the wrong direction for the movement you’re doing. Don’t look at your hands, look through them. When you do press for example you are pressing towards the horizon, not just at your imagined opponent.
All of this direction thinking – the quality of using the mind this way – is impossible if you are thinking thoughts. As soon as you notice you are thinking thoughts you’ve lost it.
When attempting this type of training my Tai Chi teacher would advise me to stop the form altogether if I noticed my mind had wandered off and go back to the start. After repeatedly doing this, your mind kind of gets the message that you’re not kidding. You really want it to stay with the body and what you’re doing for the next 5 minutes, and it quietens down and takes a back seat, allowing your awareness to come to the fore.
“Focussed awareness” is another good phrase to use to describe Yi.
Hopefully this post has helped you understand what is meant by the phrase, “All movements are motivated by Yi, not external form”, a little better. As you can see, it’s tricky to talk about. The only way to ‘get it’ is by practice. What I’m describing is a quality that isn’t a physical object or movement, so it’s hard to grasp, but with repeated practice over time it will become as real as the very device you’re reading this on.
One of the most frequent things you hear in BJJ is “move your hips“.
Brazilian teachers tend to say “escape your hips“. Which is an odd-sounding translation of presumably something that sounds better in Portuguese. In American and English it usually gets turned into “hip escape“, as in, “do a hip escape here“, “it’s not working because you need to hip escape more“.
We hip escape up and down the gym as a warm up (also known as “shrimping”) because it’s a fundamental movement you need to have in your tool box that you can pull out without having to think about it.
But why? What is it? Simply put: It’s designed to create more space between you and your opponent on the ground.
You can use hip escapes for escaping bad positions like side control and mount. But it also has benefits for attacks too. Basically a good rule of thumb is that if what you’re doing isn’t working try doing a hip escape and doing it again. The change of angle and leverage will probably fix it.
Now we know what a hip escape is, let’s get to the point of all this.
When we say “move your hips” that’s not the part of the body that you need to move from. If you just moved from your hips you’d never go anywhere. You’d just spasm on the floor like a dying fly having its last buzz. What you actually need to do is push with your toes and feet on the ground so that your hips move.
Your hips moving is the result of the action, not the action itself.
Which brings me onto Tai Chi Chuan and the dantien (the lower abdomen area of the body).
All wise and knowledgeable Internet-enabled Tai Chi practitioners know that we need to “move from the dantien” in Tai Chi Chuan. (This is the supposed secret to Tai Chi that you get told by your wise master only after you have paid the required tuition fees for a number of years. 🙂 )
Cheng Man Ching, Single Whip posture.
But again, where does the action originate? I would say that, just as in JiuJitsu, you don’t actually “move from the dantien” by originating action there. Your dantien moves, but it’s your foot that provides the impetus. Your foot pushing against the ground is where the ‘power’ comes from in Tai Chi Chuan.
(A side note here for the Order of Advanced Tai Chi Wizards of the Internet: When you get this concept of the power from the ground you will find that you can actually originate the movement in the dantien as a kind of dropping force that is then rebounded from the ground, so it’s less of a push with the legs. File this under “advanced” if it makes no sense right now and come back to it later).
What Tai Chi Chuan specialises in is transmitting this power to the extremities without interfering with it as much as is humanly possible. We know that in Tai Chi we need to be relaxed (song), which seems like the last thing you’d want to be if you have to hit something hard, but there is a method in the madness.
In Tai Chi Chuan you are trying to transfer that power – the ground reaction force – from your foot all the way to your fingers as smoothly as possible and directing it with the dantien. This is called ‘threading a pearl through the 9 crooked gates‘ in the Tai Chi classics. The gates here are the joints of the body. All the breaks in connection between your foot and fingers are the points where power leaks out. Usually we cover these things up by using muscular strength to get by – you can spend years fooling yourself with this, and it’s a very hard habit to stop.
In Tai Chi we all know we are told we should “round the crotch area” – sometimes called “Kua”, but more accurately called “Dang” in Chinese – but why? What does that mean anyway? I’m going to try and point you in the right direction with this post.
The three dantiens
There are three main dantiens in the body that Tai Chi is concerned with. Firstly there’s the main one in the lower belly, which acts as a nexus, or control point for the whole body, but slaved to it are two other dantiens – the chest dantien and the crotch dantien.
There are clear parallels here to the idea of chakras in Yogic folklore, and indeed there are more “dantiens” in the Chinese system that relate to the other chakra locations in the body too, but for the purposes of internal martial arts, it’s the crotch and chest dantiens that are most important.
The crotch dantien is located at the Hui Yin point, and shown in the drawings from Chen Xin’s book:
These dantiens are points where you can use to store force that can be used in the release of power in the way that the internal martial arts express it – i.e. from the ground to the point of application.
It’s often said that Tai Chi is “boxing with the legs”, and this relates to the use of the crotch dantien. The knees are also in the domain of the crotch dantian, so, you need to think of the legs, hips and crotch all working together.
So what is that supposed to feel like? Well, It’s a bit like sitting on a space hopper – that feeling of grasping something with the inside of your legs, but not too forcefully.
When you take up your stance in Tai Chi you should feel this ‘energy’ inside that leg arch, as if you are sitting on a space hopper. That’s not exactly a scientific way to describe it, but hopefully, you get the idea.
So your knees are involved too: when you rotate one leg forward, the other leg must rotate backwards to keep the grip on the ball. This forms the action of opening and closing, and is part of the overall action of opening and closing that is going on all over the body.
Squeezing the ball
As you move through the Tai Chi form you ‘squeeze’ this ball between your legs (just as you do a space hopper). So the crotch (the part of the body where the legs join the torso) can close on one side of the body and open on the other, but the feeling of there being something there is maintained throughout.
In Zhan Zhuang practice you get a lot of people describing holding a balloon between the legs, or a ballon supporting your limbs – that’s the same idea, and with enough practice it can actually start to feel like this.
While the space hopper or balloon may be imaginary, the feeling isn’t. It reminds me a lot of the verse in the Tao Te Ching about the value of what’s not there:
“Thirty spokes share the hub of a wheel; yet it is its center that makes it useful. You can mould clay into a vessel; yet, it is its emptiness that makes it useful. Cut doors and windows from the walls of a house; but the ultimate use of the house will depend on that part where nothing exists. Therefore, something is shaped into what is; but its usefulness comes from what is not.”
This feeling of buoyancy in the crotch dantien forms part of the way the power is transferred from the legs to the torso, and ultimately out to the fingers.
Store and release
In terms of training this power, traditionally it’s common to stand in a low horse riding stance for a long period of time. I think this is more about building leg strength than the sort of power I’m talking about though, so while there’s nothing wrong with it, I think you need a moving exercise to practice what I’m talking about.
Trying to focus on just developing this power while doing the whole Tai Chi form isn’t optimal, as there are too many other things going on at once.
It’s important to stress again that there is no actual ball of energy between your legs – it’s just a useful metaphor for helping you get the right feeling for the particular winding in the legs and hips that helps produce power through the store and release mechanism in the horizontal plane.
As you turn one way then the other, the windings of the legs results in opening and closing actions which store power, that can be released into movement.
This is another reason why you really need to turn the waist a lot in side-to-side motions in Tai Chi Chuan (usually a lot more than you think). Without sufficient turning of the waist, you’re just not getting the hips and legs involved enough and activating their store and release potential for power.
The Tai Chi move ‘Wave hands like clouds’ is a good example of this. Notice that I’m turning all the way through to the sides to get the most store and release out of the legs:
My teacher always admonishes me to ‘relax the waist’ when he’s critiquing my form. Over the years I’ve learned that what he’s really asking me to do is increase the range of movement that my waist goes through. Obviously, stiffness inhibits the range of motion of the waist, but just realising that you need to turn more than you are currently doing is a valuable insight in itself. And now hopefully you can understand the reasons why.
The Tai Chi Notebook 