Cold After Long Runs

Recently I've noticed that I've been very cold after long runs, and it's happening more and more.  Anyone else?  Various sources on forums I've search have cited several possible contributing factors:

- Poor hydration
- Hypoglycemia (and I'm switching to a lower-carb diet currently)

- Activity at tissue level to get rid of heat as a result of prolonged overheating, even though you're no longer active (note, this is not the same as hypothalamus re-set that happens during fever)

I'm going to to pay more attention to hydration but if it's #2 and/or 3 on that list, I don't know if there's anything I'm willing and able to do to fix it.  Otherwise I feel great not eating carbs all day long (normally in the form of bad food anyway) and I'm not going to cut back the intensity of my workouts just for a little discomfort at the end.  Any readers who've had this experience and/or have further information, please comment!