Don’t laugh, I had this as a present and gave a reserved t’thanks’ but it really helped my back
looks like it is restoring your ‘lordosis’, which is the basis of the McKenzie method.
Apparently he discovered it when a patient arrived and he told him to go into the consulting room and lie on the couch face down – when he went in to the consulting room a while later he saw that he had left the couch with the back part raised a little from the previous patient, so this patient was ‘doubled’ back on himself. Horrified he asked him to get up slowly, and to his surprise the patient exclaimed that his back felt much better!
http://en.wikipedia.org/wiki/Lordosis.
I get that pain – when I used to play hooker at 19 I then couldn’t walk properly until Thursday!
A good stretch for me is to try to touch my toes, but keep my lower back straight so I am trying to get my back parallel to the ground – like women do but men do a ? shape. It stretches the gluts.
Also hip flexor stretches (knee across towards opposite shoulder).
Also the TRX suspension band system is suppossed to be very good for strengthening up the back:
http://www.amazon.co.uk/Trx-Suspension-Trainer-Pro-Pack/dp/B002YIA6SM/ref=sr_1_2?ie=UTF8&qid=1326802837&sr=8-2
someone else on the forum gave it a strong recommendation a while ago.