Tight hips and Gluteal muscles can often be a contributing cause of lower back pain. Inflexibility in the Gluteals can contribute to excessive load on the lower back rather than the movement happening in the hips where it is supposed to be. Try this simple exercise to help to loosen up your hips and Gluteal muscles.
Sit on a chair with your feet resting on the ground then move your right ankle up to a position where it rests on your left knee. From there arch your tail bone away backwards while pushing your chest bone forward, after a few breath cycles in this position you can relax your neck and hang your head forward. You can increase the stretch even further by pushing your right knee down towards the floor. Then repeat the procedure on the other side. This is an easy exercise that can help with the long-term health of your hip and back that you can do anywhere while sitting. (*avoid this stretch if you have a hip replacement).
Work your way up to hold this position for 60 sec and repeat 3 times per day for best result.