I think it's not so much that we do things that make it tight. It's that the things we do make it screech if it is tight, and almost everyone's is. Sitting is the biggest culprit but we can hardly give that up
The roller is really good. There are also stretches using weights that can be very helpful but that's one for the physical therapist. If you rip that sucker and develop scaring it will be twice the bitch to work out.
Good luck with it