This video from fitness trainer Yuri Elkaim demonstrates a core workout for the absolute beginner. These exercises are good for people who have never worked out or who have sore back. He explains abdominal bracing, which adds stability to the core and spine, and works the muscles by contracting them. The first exercise is a bird dog. Get on your hands and knees and relax your spine and do an abdominal brace. Clench one fist and put that arm and the opposite leg out to the side, hold for five seconds, and repeat on the other side for 10-12 reps. Next exercise is the plank. Get in the position with both elbows and both toes on the ground and hold it for as long as possible, 30 seconds to a minute. Next he shows the side plank. Lie on your side with forearm below your shoulder, and hips raised for a more advanced exercise. Lift up and hold the position for about 30 seconds, and repeat on the other side. The last exercise is a hip bridge. Lie back with feet flat and knees up. Squeeze your butt cheeks then raise hips off the floor, hold for about five seconds and relax. For a more advanced exercise, lift the feet off the floor one at a time. This is a good fundamental workout to begin to build strength in the abs and core.