I have this habit for as long as I have been alive. Some of my family memebers have it too including my lil neice. When attempting to sleep I will shake my foot - one or both. I sleep on my stomach. It often keeps me awake but, sometimes helps me sleep. Sometimes, I can be so dead tired but can't seem to stop shaking my foot. I guess it is hard to explain w/out seeing it. It doesn't bother my husband but, past, "sleeping partners," use to not be able to sleep near me b/c of it. What do you guys think...RLS?