I know I should stay moving during flights. I know it's no good for my health to be sitting for long periods of time. (Sitting is the new smoking, after all.) I also know scary things like deep-vein thrombosis are very real risks when flying, too. Nothing is more unnatural than being crammed into an economy seat for hours on end.
The reality is I don't end up doing moving from where I'm wedged. Even if I always try to snag an aisle seat just for the freedom of being able to be up and down whenever I please.