Please choose the correct ending to complete the given sentence: Health: [header] How to strengthen your lower back [title] Make a hip bridge. [step] The hip bridge also works to strengthen the muscles in your lower back and core that support your spine, putting you at less risk for lower back pain. Lay on your back for this exercise with your knees bent and feet flat on the floor, as you did for pelvis tilts.

Ending1: [substeps] Keep your knees on the floor until your feet reach the floor, then lower to starting position without moving. On the second rep, you can do a full hip and knee bridge. Ending2: [substeps] Lift your hips toward the ceiling, keeping your knees bent and engaging your core. Stop when your hips are even with your knees, such that you could draw a straight line (or a bridge) from your knees to your shoulders. Ending3: [substeps] You can do this in a standing pose with your knees straight behind you. Place your hands behind your head, a few fingers spread out. Ending4: [substeps] Place your ankle over your toes, keeping the hip a few inches away from your heart. Slide your knee through the gap between the outer seam of your ankle (the shoulder muscle) and the floor, making sure you aren't resting on your heel.

Answer format: ending1/ending2/ending3/ending4