Hip rocking is a very simple way to introduce a neutral, stable spine and hip mobility. This is a safe, non-loading position to train your spine to be stable and your hips to move. It is trickier than it looks and often takes a while to get right, especially if you have some dysfunction in your hips or lower back. Sitting long hours will make it difficult to even reach neutral spine in this position for many people. Start with 10 reps.