My PT was telling me that the back muscles loose the fight in a tug-o-war with your hamstrings.  So they got me stretching those steal cables a bit.  The other usable advice i got from them is the old sit-ups or crunches.  The word is a strong front helps a support the back and visa-versa.  However, i graduated from school with a fine arts degree not a PHD, so you can basically ignore me and GET BETTER!!!