A few New Year's ago I mentioned that I was interested in taking up meditation. I have not (I still would like to). However, for over six months now I have practiced yoga on and off.
As someone who has worked at a desk for the last five years and hunched over a computer too much in the last fifteen, I've had some back issues already.
I have found that weeks when I have been able to do yoga, it has helped my mobility greatly and reduced stiffness and pain. I have found to make sure NOT to stretch farther than I naturally can for a pose, or I will be sore and possibly worse.
I am glad that my girlfriend Tressa introduced me to yoga and recommend it for others with back issues that think it is just hype