I found wearing flight socks helped, not very glam, but did the trick. The other thing is that there is a pressure point a couple of inches down from the crease at the back of your knee and about an inch or so in from the inside of your leg, which if massaged makes the blood flow quicker and alleviates the terrible feeling of having to move your legs. Haven't explained it very well, but maybe some medical type person who had an inkling of acupunture things might be able to locate it for you? You have my sympathies anyway.