Please be advised that I do not own the rights to any of these youtube links. I have chosen these particular links as they demonstrate the way to perform the stretch in the clearest manner.
If your upper back is tense, the likelyhood is that your pecs are tight, this exercise will help to release them.
If you sit most of the day and experience low back pain, you may have a tight glute muscles that are causing the pain. These two exercises can help.
This is the lying down version do this twice a day at night and morning and hold for 30 seconds each time.
This is the sitting down version try and do a couple of times during your day – make sure your feet are flat on the ground again hold for 30 seconds each time