Both the rectus abdominis and transverse abdominis are two muscle groups to aim for. It’s important to note that you can’t spot-reduce your abdominals. For your abs to show through, you’ll need to remove the layer of fat over the abdomen. Cardio workouts and a healthy diet are the key to success. Try these nine ab exercises as part of your overall fitness program, including Pilates Pilates and the 100-count crunch. For example, “the 100” is a redesigned crunch that you hold for 100 counts. Your deep stomach muscles can also be strengthened and stretched by machines like the reformer.