I get this during growth spurts really badly, and for me it's only at night. It is MADDENING isn't it?! I got it in my arms and hands as well as my legs and sometimes I just had to put baby down mid-feed for a break so I could shake my restless limbs around while he cried!! It's the most horrid sensation. I thought maybe it was a sign that I wasn't getting quite enough of something (magnesium? Potassium?). I tried to take vitamins daily and bathe every night to relax my body properly. I'm not sure if it helped... Hard to say, because it wasn't all the time, and as he is getting older, it seems to be getting less and less frequent anyway I'm sorry I don't have any good suggestions. I know it can be unbearable!