Wing Chun Kung Fu Training Stance - Is it healthy?

Hi there,

So I've been studying a form of Kung Fu called Wing Chun for about a year now, and one of the foundations of the system is a stance that is supposed to strengthen the legs to create a stable stance. The idea is that you can use the more stable stance to direct force applied to your arms and upper body into the ground, so that you appear solid when someone hits you, and you don't fall backwards. We use different stances in practical application, this is just a static stance used for training.

Here is a video of a well respected Wing Chun Master demonstrating the stance in an online tutorial:

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Apparently it falls into the bracket of quigong, which refers to a type of stress position in Chinese martial arts which is used to strengthen muscles and generally build strength. We are expected to stand like this as regularly as once a day, for anything from 15 minutes to over an hour. (I also asked my instructor for a bit more detail about the lower end of the stance and he said the weight should be kept on the heels - the same as everything else we do - and the knees should be held above the toes.)

So the actual fighting stance that we would use is with one foot forward - There is another video of the same guy demonstrating the fighting stance here:

Biu Mar Stepping

We carry about 70% of our weight on our back foot, but because the design of Wing Chun is ambidextrous, this stance is supposedly designed so we can train both legs as the back foot at the same time. (It's difficult to explain the whole concept, I don't think I've done a particularly good job of it, so feel free to ask questions!)

Anyway I'm also a construction worker whose body is suffering from eleven years of bad heavy lifting (having never really been taught how to do it) so I joined a gym and got a few sessions with a personal trainer to try and sort my posture problems out. Apparently my hips are tilted backward too much, so he's just teaching me to squat with me core straight, amongst other shoulder problems etc. Anyway I digress...

I was talking to him in a session today and he asked me what I do in the Wing Chun classes, so I showed him the training stance, to which he exclaimed, "Oh my God!" and proceeded to tell me that it looked like a really weak, unnatural position to be in. He explained that when your knee is pointing inwards in relation to your hip, you're using one set of muscles, then when you turn into the fighting stance your knee is pointing out, and you're using a completely different set of muscles, so he says it's very likely that training the one stance won't have any effect on the other at all. His main problem with it was that he had been teaching me to keep my knees out while I squat, and he said this totally contradicted everything he had taught me.

I was really disappointed because up until now I was quite impressed with the similarities between my Wing Chun training and what I was learning in the gym; mainly the ideas about keeping the core straight, the shoulders back, and producing power from the heels. From what I can tell, Wing Chun has always stood on its own, contradicting the conventional wisdom of other martial arts that say you have to stay on your toes and lean forward in order to get power into a strike, and what I was learning in the gym seemed to correlate more with what I was seeing in Wing Chun classes than it did with anything else. Until now, of course.

So I thought I should get some kind of professional, learned opinion from people who really know the science of human physiology - what muscles this position actually exercises, in what way does it exercise them, if it is putting any undue pressure on my joints, etc. Basically,what results you would expect to have from standing like this regularly. Most importantly, I need to know if it is going to do me any damage!

Any help or insight would be great.