This pose helps to fortify the backbone and the glutes. Also the breathing can benefit from this exercise because the bridge pose can improve the lung capacity.
Lie supine on the floor, your arms at your side and hand palms facing down
Bend your knees and set your feet on the floor, close to the sitting bones.
By breathing press your legs and feet actively into the floor, then lift glutes, abdomen and chest off the floor. On the contrary, the shoulders and the arms stay on the floor. Lift the buttocks until it is easy for you to leave the shoulders on the floor.
Stay in this pose for 5 minutes, breath uniformly
By exhaling lower the back and the buttocks and bring them to the floor. Stay some minutes to observe the effects of this pose on your body, of the contact with the floor, without judgments, all that you see is right