Charlie,
When I first start practice SFQ, my standing posture was incorrect and caused me back pain. Before I practice with the correct standing posture, I have to let my body heal first. I did the active exercise with one change.
I did not bend my knees and just stand with a relaxed posture.
I found myself continue to benefit from the practice.
Later, I returned to the position as Master Lin presented in the lesson.
Take it slowly, the best way for yourself, if sitting can carry you through the exercise, do it that way first. In time, you might found your back pain is gone and able to go on to “your” next step of practice.
