PC version. So I'm moving really slowly. Not over-encumbered slowly: I'm a hundred pounds under my limit. And I can sprint, but that is also really slow. I tried reloading the game, fast traveling, sneaking and unsneaking, turning into a vampire lord, and having the vampire lady hit me with ice spells. Nothing has changed it. Setting my run speed in the console does not change it. I have just enough major mods installed that uninstalling them all would probably render the game unplayable. Loading an earlier save fixes this issue. I would rather not have to continue from an earlier save. Does this problem sound familiar to anyone?