Lie on your back with your knees bent, your feet flat on the floor or a mat, and arms at your sides. Cross your arms over your chest, keeping your middle and lower back flat on the floor. Raise your head and shoulders off the floor slightly. Raise up only far enough to get your shoulder blades just off the floor. It's okay if you can't go up too far at first. Hold this position for just a few seconds. As you get stronger, you can hold it for 5 to 10 seconds. Gradually return your upper body to a relaxed position on the floor. Do 5 repetitions.