I don't post it much, because it's boring, but I do like to update everyone on what I do on my "off days" periodically because although boring, it is important.
These sessions are mostly focused on lower back, and tense to consist of 3-5 sets of 10-15 reps. Exercises used will be cable pullthroughs, glute-ham raises, back extensions, dead-hypers, incline sit-ups, lis lifts, dumbbell side-bends and planks.
This generally takes me an hour and I usually get two sessions like this in per week, in addition to my main sessions.