Abdominal muscles are important for running since they provide all the balance and support to you when you run. Having a toned and strong core is important for anyone who does any kind of physical activity for extended periods. It helps to prevent injuries. A strong core also helps in stabilizing the spine and pelvis which reduces back pain. Doing ab exercises regularly will strengthen your core and help you achieve a stronger, more toned and more defined core. This will also help you run faster and further.