exercise, but it gets easier. I honestly noticed an improvement almost immediately after doing the exercise the first time. It didn't stick, but after a couple months I noticed more lasting results. You have to keep doing it though, probably forever; missed about a week when I was sick and started noticing more pain.
But you could definitely start slow and build up to 12 minutes.
One other thing: I did about 20 sessions of PT last year, saw some marginal improvement, but nothing like this, and it's free!