Is your low back aching a lot while you sit at work?
A common misunderstanding is that you should sit bolt upright when you sit in your office chair - rather like the old fashioned 'prim and proper' secretary.
Perhaps you've been asked to do this to stop you slouching or slumping in your chair as you use keyboard or mouse, and stare at the computer monitor.
Well, sitting upright can be just as bad, as it still places quite high compressive forces at the base of the spine.
Try 'reclining' in your chair, with legs out in front, and your bottom slid nearer the front of the seat.
If your back problem is a disc type of problem, this can keep the 'strain vector' off the injured part of your disc and thus reduce pain.
Reclining in your chair may well help in some cases, but like all sitting related problems with back pain, you need to take regular breaks.