A Core strength refers to the strength of your stomach and lower back muscles. How they interact to keep the pelvis and lower back stable is ‘core stability’. While overall abdominal strength and lower back strength play an important role, most people who are moderately active have sufficient strength in these muscles. If people have a problem with their core strength it is usually the deeper, smaller muscles of the stomach where they have a problem.
Weakness in the deep muscles known as the transverse abdominus leads to many potential problems and muscle imbalances. From a performance perspective, if your core is stable, and you can activate your lower abdominals during movement, you provide your muscles with a more solid base to work off which, in turn, means more powerful movements and less wasted energy.
The starting point in all this is to determine how strong or weak your core really is. Try this simple test:
Lie on your back with your legs bent at 90 degrees, feet on the floor. Lift your feet off the floor. If you cannot prevent your lower back from arching, your core is weak. If you can keep it straight, but can feel your upper stomach muscles working, your core is weak.
Due to the specialised nature of strengthening these small muscle groups, it is advisable that you seek professional advice on how to execute the correct movements. Once you can do them correctly, you can do them twice per week indefinitely.