@lilianna "How heavy a backpack."
I think that would depend upon each of us and what we were able to comfortably weight ourselves down with, handle etc. ..... at first..... and maybe gradually increase the weight as we experience it all. The weight is to help one to bring about a type of breathing that would help move the mucus up and out....from my understanding.
I do postural drainage and need to incorporate the weighted backpack when I do my walking.
Barbara