For me they go away almost immediately if I wake up all the way. And yes then stretching and moving helps. This is great in the morning. But at night when I feel them when I am starting to fall to sleep if I wake myself up to get rid of them it means that I will have to try to fall asleep again and they will be back. So vicious cycle. That's why now when falling asleep and I feel them I do everything possible to remain calm. relaxed, ignore them and know they will be gone if I just go to sleep. Same thing if I wake up in the middle of the night...relax, go back to sleep. ( Of course in the beginning I got up terrified which only made them worse and couldn't get back to sleep very well.) We are all a little different in our experience but I hope this helps. I am in excellent healthy, no medications, and anything else to explain why it happens.