If your back feels stiff and tight, try lying on the floor for a few minutes and hugging your knees into your chest. This is a safe and effective way to release tight muscles in your back, legs and groin.
Lie on your back with your feet flat on the floor and knees bent (you can place a small folded towel under your head for comfort). Bend your right knee into your chest and pause. Check that the back of your hips remains on the floor. Elongate your neck by moving your shoulders down away from your ears. Tuck your chin in slightly.