So, there it is - My thoughts on some aspects of fangsong:
Everybody who has ever done zhangzhuang feels pain.
So, if your back is cramping up after 10 minutes of zhangzhuang and your shoulders are aching (which is how it usually is), what should you do?
Drop your shoulders... And let go of the tension.
Easy to say, but often seems quite impossible to achieve.
I bet most of you already heard Laoshi telling you that many times and more... Life would be less painful if you paid better attention to our teacher
I must say - my first times to do zhangzhuang by myself ended in about 5 minutes with my shoulders so sore I really didn't feel like continuing with form and solo practices. That was a whole lot of time ago though and I can now easily stand 15 minutes without any difficulty at all and 20..30 minutes, although not easiest thing in the world, are quite affordable result (I really should be practicing more, I know).
There is a trick in "letting go" of the tension that I only realized quite recently - we do it all the time. We just keep thinking of it as conscious movement and thus rule it out from fangsong.
Often I used to picture fangsong as something that just had to happen one day. Something, that when I wait patiently enough, just takes over and turns everything right... Well, actually, fangsong is much much simpler than that and something we use in our everyday life more often than we suspect...
An example of fangsong in your everyday life.
When you pick up something, say a cup of tea, you are using muscles of your hand to hold up that cup, so this is not very relaxed - depending on how hot is the tea and how big is the cup, you will most likely want to relax and you put down the cup.
Now when you put that cup of tea down, you are doing it by letting go the tension in the muscles that you used to hold up the cup.
You think of it as "moving your hand" or "putting down the cup".
And you are absolutely right.
While you are holding the cup, you are not expecting gravity to take over the control and pull down your cup of tea. (In case that happens, you'll usually end up with wet carpet, broken china and mild burns on your thighs - the kind of things you usually are trying to avoid)
So you are actually working against the gravity. So as long as you're holding up the cup it will never fall down. Same goes for your elbows while you are standing in zhangzhuang.
You need to stop thinking of fangsong as something magical that "just happens" (I know I did) - something the gravity has to do for you and start thinking of it as of things you need to adjust in your body structure.
As you "move" your hand to put down a cup of tea, you also need to "move" your elbow in a more favorable position.
That won't get rid of all the pain though - the pain just gets more focused around single points rather than whole body parts... And you'll find there will be less pain as well as you are now not working against yourself as much, so - 30 minutes .. is still good goal to achieve. but now it is much easier