There's a difference between not warming up and not stretching. Before a run you should warm up by brisk walking, gentle running or dynamic exercises such as knee raises and kick backs. After a run you should do your static stretches, and at other times during the day when you feel stiff.
I don't like chemical rubs and tend to use a wheat pillow instead. Heat it up in the microwave for 3 minutes and go to sleep with it under your calf or thigh, depending where the problem is. It smells a lot less than rubs, doesn't get on the sheets, and doesn't reduce your chances of getting intimate with your partner
Also good in place of a hot water bottle in winter
Edited: 05/01/2013 at 20:21